Hands-On Rockville RXH-F5 5 Channel Amp Review – The Good And Bad To Know

Rockville RXH-F5 5 channel amp review featured image

Having tried several of Rockville’s line of budget car amps, I’ve come to appreciate that they’re often a good value with lots to offer.

5 channel amps are a special group of car amplifier and there aren’t many to choose from – especially affordable ones. But is this one a great option or should you pass it by?

In my Rockville RXH-F5 5 channel car amplifier review I’ll share with you what I’ve found. You’ll want to know what I found out during testing before you buy one!

Contents

Basics first: Getting to know the Rockville RXH-F5

Image of Rockville Phenom series amplifiers with RXH-F5 highlighted

Phenom series amps are highly affordable class A/B amps with a traditional amp design inside. Some of the best-selling Rockville amplifiers from the Phenom model line are shown here with 2 true RMS power ratings (2 different measurements are used). The RXH-F5 adds a class D subwoofer channel for lots more power.

One of Rockville’s Phenom line of budget-priced amps, the RXH-F5 amplifier shares the same basic design features as its siblings. If you’re not already familiar with Rockville products they’re a relatively new company with a variety of budget level car audio products.

What helps set the Rockville line of amps apart from other budget brands are the Consumer Electronics Association (CEA) 2006 industry standard power ratings. That is, unlike many budget amps you’ll find when shopping reliable power ratings are provided.

More about the Phenom series of amps & the RXH-F5

Like most amps in the product family, the F5 uses a traditional A/B amp design for the front and rear speakers. However, it adds a 5th channel powered by a class D supply dedicated to driving one or more subwoofers.

They also list (as do some other manufacturers) another RMS power rating that’s measured differently. Not to worry though as I’ll explain more about that later.

In the Phenom family you’ll find several types of amplifiers:

  • 4 channel models
  • 2 channel models
  • 5 channel models
  • Mono (single) channel bass amps

Rockville also has a product line called the DB series. However, the Phenom series provides slightly better sound quality specs and features the DB series doesn’t offer (although the DB series are still a good choice as well). Phenom amps also offer more channel configurations (like this 5 channel version).

Phenom series amps are only a few dollars more than DB models and many also offer more features so they’re hard to pass up. Many sell for around $90-$160 or so making them an affordable choice for many.

Pricing & power ratings

Rockville RXH-F5 5 channel amp in box image

In terms of price, the RXH-F5 sells for about the same as comparable amps from Hifonics for example at close to $150-$165 or so.

Unlike its sibling the 4 channel RXA-F1 I reviewed here, there’s no twin marine version with 5 channels offered.

As power ratings can be a bit confusing I’ll try to break down what you can expect to get for your money.

CEA-2006 compliant RMS power ratings (at 1% THD):

  • 4 x 50W + 1 x 350W @ 4 ohms
  • 4 x 75W + 1 x 500W @ 2 ohms

RMS (“uncertified”) continuous power ratings:

  • 4 x 100W + 1 x 700W @ 4 ohms
  • 4 x 150W + 1 x 1000W* @ 2 ohms *(company claimed rating)

Note that CEA-2006 are guaranteed and based on a stricter industry standard way of measured useable amp power, while the standard (“uncertified”) continuous power ratings are normally measured to clipping.

A reasonable expectation for the power you can expect to get is the CEA-2006 power ratings plus a bit more.

Unboxing and first impressions

Image showing unboxing the Rockville RXH-F5 amplifier

I finally got my hands on it! My Rockville amp finally arrived and I got started unboxing right away. Inside the box was the amp’s production certificate, accessories, and manual. It’s also safely packed inside snug foam inserts holding it in place which I prefer over styrofoam.

I opened the box up and got a good first impression.

After opening the amp box inside you’ll find the amp’s production certificate stamped with both the CEA-2006 power ratings and the serial number. It’s a nice touch.

It’s not as detailed as the manufacturing certificates provided with some much more expensive amps (like those by Rockford Fosgate, MTX, and so on) but it’s still a nice touch.

The certificate gives the impression that each amp has power measured individually during production but that’s actually not true, as I’ve noticed all amps of the same model have the same power rating stamped inside. However, in my opinion, that’s not really a problem.

What we really care about is having the amp meet its rated power output as advertised. I’ll cover that topic later below.

RXH-F5 5 channel amp package front and rear images

The RXH-F5 is well-packaged and has the power ratings & features clearly labeled on the back which is great. However, despite being marketed with true power ratings (CEA-2006 & standard RMS specs) they still list the power on the box as “peak power.” Why? That makes no sense to me.

All in all, my RXH-F5 was well-packaged and everything looked good. Despite being a budget amp line I’m happy with what I found after opening it up. What I don’t like for is the use of “peak” or “maximum” power ratings on the box like less reputable amps use (as seen in the lower right corner on the front of the box above).

I just don’t get that in this day and age, especially since part of Rockville’s advertising is based on their realistic power ratings. However, as it’s not being used as the power ratings for sales ads, I’ll overlook that.

What’s in the box?

Image of the items included with Rockville RXH-F5 5 channel amplifier

Let’s keep moving and get to more good stuff. What comes in the box?

You’ll find the following inside:

  • A nice owner’s manual
  • Warranty card (1 year warranty)
  • Speaker level input harness adapter
  • Four #8 1″ pan head screws with non-damaging rubber washers
  • The amplifier

The included screws are #8 pan head screws and should work well for most installations. I used them myself during testing. They’re definitely the right length so you shouldn’t need to buy any others.

Installer tip: I recommend you drill pilot holes before driving the screws into the mounting surface when mounting it.

That’s because driving screws into some materials without pilot holes (using a 1/8″ bit) can cause them to split & crack badly. For soft woods like pine if making your own DIY car amp rack however that’s usually not a problem. For other materials like medium-density fiberboard (MDF), particleboard, or fiberglass it can be a big problem

The included rubber washers are a non-scratch/non-marring type used between the screws and the amp’s mounting hole surface. This prevents damaging the plastic mounting feet as the amp doesn’t use metal mounting tabs as many do.

So far, so good. One thing I did notice, however, is that the hex wrenches you need for the wiring terminals aren’t included.

You’ll need to get your own with the following sizes:

  • +12V & ground terminals: 4mm (5/32″)
  • Speaker & remote wire terminals: 2mm (5/64″)

Bondhus 12232 8 hex wrench setThe amp doesn’t include the 2 hex wrenches you’ll need to use on the wiring terminals. I recommend a good budget priced set like these I found at Amazon.

One great thing I like is that you can use up to 4 gauge wire for the power and ground terminals!

Build quality and fit & finish

Closeup images of Rockville RXH-F5 amp

Close-ups of the RXH-F5 from different angles to show the build quality & fit and finish I found. I found it to be a well-built amp that looks better than I expected for a budget amp line. It’s also very attractive despite using a fair amount of plastic on both ends. There’s a nice black brushed metal center inlay that I really like.

I gave it a good “once over” to check the build quality, assembly, and find any noticeable flaws. Overall, it’s a good-looking amp and well made. Fit and finish are good with no noticeable issues.

There’s a lovely black brushed metal centerpiece in the amp’s chassis with the Rockville logo and emblem. It’s a nice-looking touch and adds a bit of class you won’t mind showing off.

General design and finish quality

It’s the same tried-and-true design: An aluminum heatsink chassis.

However, the Phenom series of amps have a slightly unique design in that the sides are a dark gray instead of black like the top. There are also some false hex-head chrome screws in the centerpiece which adds a good-looking style accent.

Front and rear end sections are made of plastic and serve as the mounting feet. That’s my only complaint because metal mounting feet are a lot more durable and can take more force without warping or cracking. You’ll need to be careful not to overtighten the mounting screws when installing it.

Overall, the fit and finish are very good. It’s a good-looking amp and you might guess it’s more expensive than it really is if you didn’t know better. I like it.

The downside of being a budget amp is that to keep costs low older technology is used. Unlike some of today’s more compact amps, the tradeoff is the size since a more cost-effective design is used for the electronics.

A note about budget amp quality

I’ve owned and have tested several Rockville amps and a few times I’ve noticed a few minor quality control issues.

In 1 or 2 amps I’ve had a dial or two (gain or other adjustment dials) were a bit misaligned with the end panel opening. However, that’s a fact of life sometimes for budget products and it didn’t affect how I used the amp.

Overall, though, I’ve been pretty happy with how the Phenom series amps are built and mine had no manufacturing problems at all.

Front and rear panel details

Closeups of the front and rear ends of Rockville RXH-F5 amplifier

Shown: Front and rear panels with controls and wiring connections for the amp. For a budget amp, it’s actually very good. Wiring terminals need hex wrenches to use them, but you’ll get a much better and reliable connection than most budget amps use. Controls and input jacks (and more) are clearly labeled and easy to understand.

Wiring terminal quality & installation notes

For an amp in the budget price range, you’d think you’d get the same cheap wiring terminals that so many other amp manufacturers use. That’s not the case here, and I’m really happy to see that!

Wiring terminals use a solid machined metal design – instead of using a Phillips screw terminal style you get a much better design with 360° contact on your wiring.

Hex head screws tighten within each wiring terminal for a high-current & reliable connection.

During testing I found them to be very secure and good-looking too. While the openings do face out at a very slight downward angle (only a few degrees), I didn’t really notice it when installing it.

Note! Don’t use a cordless screwdriver or drill to tighten the wiring terminal screws. You could potentially strip the screws or break your hex bit. I recommend doing it the “old-fashioned” way: by hand.

The amp uses two standard 60 amp automotive fuses (replacements can be bought online or in stores if needed). Labels are clear and easy to understand, but for some reason, the speaker wiring bridge connections aren’t provided.

Bridging is easy though – just check the owner’s manual to be sure you’re using the correct terminals (Left channel positive & right channel negative).

Control panel & audio jack diagram

RXH-F5 amplifier control panel labeled diagram

Lots of good stuff packed into a small panel! For clarity, here’s a diagram showing all the functions & what they’re for.

There’s a lot packed into the control & input panel end of the amp. There’s a lot to cover here so I’ll try to keep it simple to understand and be right to the point.

The control & input panel has the following:

  • Speaker level input harness connector
  • Front, rear, and subwoofer (mono or stereo) inputs
  • Front crossover switch: Full range or high pass
  • Front crossover adjustments: High pass frequency – 50Hz to 3KHz
  • Rear crossover switch: High, full, and bandpass options (bandpass allows low pass use)
  • Rear crossover adjustment: High, low, and bandpass high/low options
  • Status & protection indicator light
  • Front, rear, and subwoofer level adjustments
  • Rear channel bass boost adjustment (0/6/12dB)
  • Subwoofer 0/180° phase switch
  • Bass remote jack
  • 2/4/5 channel input source switch

Each end of the amplifier also has 2 plastic areas resembling grills for air vent cooling. Immediately next to those are the mounting screw locations.

Crossover controls

While it might seem confusing at first, in all reality the controls are pretty straight forward. Fortunately, the owner’s manual is really helpful at explaining everything.

You have the crossover modes to choose from:

  • Front channels: Use in full range high pass mode
  • Rear channels: Full, high, or bandpass (which can be used for a low pass as well)

A “bass EQ” (bass boost) is available and provides 2 fixed levels of boost: 6dB and 12dB to the subwoofer channel. The bandpass filter mode is only offered on channels 3 & 4 and provides a lower adjustment of 15Hz-1KHz and the upper limit is adjustable from 50Hz-3KHz.

Thanks to this, unlike the front channels it’s possible to use it as a low pass filter if you like. Unlike some other Phenom series amps (like the 4 channel RXA-F1 I tested) there aren’t any crossover multiplier switches to add more flexibility.

Speaker level inputs – Another cool feature!

Image showing a Rockville car amp speaker level input harness

Rockville Phenom amps provide speaker level inputs in case you don’t have RCA jacks handy on your head unit. Factory radio? No problem! In fact, to my surprise, there’s an auto-on remote feature built in when using this.

One of the best features of the amp is the auto-on option when using the amp with a factory system.

When using speaker level inputs, you won’t need to connect a remote wire! The amp will automatically switch on or off when it senses signals from your stereo.

While that’s excellent and can save you a lot of work, there’s a minor gripe I have: Front and rear speaker level inputs aren’t labeled in the owner’s manual for some reason.

The +/- speaker input wiring is labeled on the amp, so you’re good there. However, the owner’s manual doesn’t tell you the front/rear wiring colors, so you’ll have to find that out that at installation time.

The Rockville’s amp guts revealed – What’s inside?

RXH-F5 amplifier internal view labeled

Internal view of the RXH-F5’s components. The amp uses 2 types of power supplies for the different channels: Front & rear channels are powered by a traditional class A/B design while the subwoofer channel has a dedicated class D supply for high power output.

I opened my amp to show you all the gritty details so you can see what I found.

Overall, after giving it a close look-over I can say it’s well done. While it’s a single-sided circuit board (conductive traces are on the bottom of the PCB) there’s a lot of solder added to the traces for extra conductivity and current flow with less resistance.

Front and rear channels use a Rockville’s own version of the traditional class A/B power supply design. The high power output available from the dedicated subwoofer channel relies on a second class D design in the middle of the circuit board.

Components used are mainly older style (but good) through-hole type for lower cost. That’s not a bad thing, it’s just that you need to understand that to save money compromises have to be made.

Design specs & notes

Standard bipolar output transistors are used. Undervoltage & high-temperature protection is built in as well. The adjustable control potentiometers (used for gain, crossovers, and bass boost levels) are of good quality, too.

Switches seem to be of good quality and have a good feel to them as well. No complaints about the parts used to build it.

Note: The company also advertises that the Phenom amps use audiophile-quality capacitors and feature a “class G” design which basically a slightly modified version of a standard class A/B car amp for the main channels.

Basically this means while it’s a traditional design, the power supply reduces output depending upon power needs to help improve overall efficiency.

Specifications

Rockville RXH-F5 Specifications
  • CEA Compliant Power Ratings:
    • 4 Ohms: 550 Watts (4 x 50 Watts + 1 x 350) at 4 ohms and 1% THD+N
    • 2 Ohms: 800 Watts (4 x 75 Watts + 1 x 500) at 2 ohms and 1% THD+N
  • RMS Power Ratings
    • 4 Ohms: 1100 Watts (4 x 100 watts + 1 x 700 Watts)
    • 2 Ohms: 1600 Watts (4 x 150 watts + 1 x 1,000 Watts)
  • Front/rear: Class A/B, channel 5 is mono class D
  • Studio-Grade Bipolar Output Stage Transistors
  • Fully Adjustable 12dB/octave crossovers
  • Ch1/2: High pass 50H-3KHz
  • Ch3/4 Low Pass 50 Hz – 3 kHz, high Pass 50Hz – 1KHz
  • CH5 low pass 50Hz – 250Hz
  • High level inputs w/ auto-on feature
  • Thermal/short circuit protection circuitry
  • Optional bass remote included
  • Bass EQ: 0/6/12dB boost selectable
  • 2 Ohm stable stereo
  • 4 Ohm mono bridgeable
  • 3 Channel Mixed-Mono Capable
  • 2 Ohm subwoofer capable
  • 2 CH / 4 CH / 5 CH Input Mode Selector
  • Fully Adjustable Subsonic Filter: 15 – 50Hz
  • Crossover Bandpass Control
  • Subwoofer Phase Control (0/180°)
  • Mute and Delay Soft Start System
  • 8 Volt Preamp Circuitry
  • ELNA Brand Audiophile Quality Capacitors
  • Status Mode LED Indicator
  • Minimum THD at Rated Power: < 0.05%
  • S / N Ratio: > 100dB
  • Frequency Response: 10Hz – 40KHz
  • Damping Factor: > 200 @ 100Hz
  • Dual 60 Amp standard Maxi fuses
  • Dimensions (W x H x L): 8.6″ x 2.0″ x 16.1″ inches

There are quite a few features you’ll get for your money and the specs are pretty good for its price range. However, real-world testing is what counts in my experience.

Understanding the RXH-F5’s power ratings

Diagram explaining CEA-2006 vs uncertified RMS car amplifier power ratings

It can definitely seem confusing when you first look at the amp’s power ratings. However, there’s a logical reason they offer 2 RMS power ratings. Continuous root mean square (RMS) power ratings existed long before the industry standard CEA-2006 method of rating an audio amplifier’s power came along.

They differ in a few ways, but both are useful when comparing similarly rated electronics:

  • CEA-2006 power ratings are measured when an amp’s power output reaches 1% distortion. This is a lower number than what an amp is capable of producing (with higher distortion) in nearly all cases.
  • The continuous RMS power (sometimes called “uncertified” power) is a measurement of the power an amp can put out continuously until the signal begins to clip.

Clipping is the point at which an amp can’t amplify the input signal anymore. It’s also a terrible form of distortion and can potentially damage speakers. That’s why we try to avoid it always.

The “uncertified” rating is how much “useable”, or how much power you can continuously expect to get, out of an amplifier for the rated speaker load.

The important thing to remember is this: When comparing car amps, compare similar power ratings. Otherwise, it’s not a fair comparison and can be very misleading!

Fortunately, the Rockville amps are industry certified to deliver at least the CEA-2006 power ratings advertised. In fact, they’ll exceed those up to the uncertified (continuous) RMS ratings.

A quick note about the signal-to-noise ratio (SNR)

Signal to noise ratio car amp diagram

The signal-to-noise ratio (SNR) is measured in decibels (dB) and is a way of comparing the amount of “hiss” or base noise level an amp produces compared to the musical signal. A higher number is better, and typical car amplifiers are around 90dB and above.

Rockville lists the Phenom series (at least several of the prime models) as having a SNR ratio of greater than 100dB, which is very good. You’ll have to pay a lot more money to get even higher numbers, and it’s really not worth it unless you’re a true audiophile or want competition-level performance.

Note that they don’t specify how that’s measured. In some cases the SNR is measured at 1 watt, and/or at a higher power output where amps perform better. Those more specific rating specs are a bit rare among car amps, though.

My test setup and installation

Rockville RXH-F5 5 channel amp review test setup diagram

Shown: My test setup used for real-world testing of the amp during daily use and with many types of music.

Alright, on to the good stuff! Once I got the amp I was able to install it, tune my system, and give it a real-world test.

Installing the RXA-F5

Images showing test installation of the Rockville RXH-F5 amplifier

Installing the RXH-F5 for daily testing and putting it through its paces. I use a test installation setup for checking out amps, especially with a very high-quality audio signal source.

I used my test setup I’ve installed just for this purpose to power and supply a super-clean audio signal to the Rockville amp.

Installing the RXH-F5 is fairly easy although I did have to find my own hex wrenches for loosening & tightening the wiring terminal screws.

I did find that the speaker wiring terminals can be a bit tricky, as they’re a bit deep inside: You’ve got to be sure you’ve got the speaker wire inserted fully deep into the wiring terminal. Otherwise, after tightening the screws it’s possible to pull the wire out and you’ll have to start again.

No problems with the power & remote wire terminals, however. They’re easy to work with and everything was good. After installation, I gave the amp around 1 day for burn-in time to be sure any initial problems would show up and the parts had a chance to break in a bit.

NoteIf you’re using a head unit with only 2 channels instead of 4 (front/rear) and/or a dedicated subwoofer RCA output, you can use the 2/4/5 channel input switch to avoid needing RCA “Y” adapters. The remaining channels (including the subwoofer) will derive a signal from the 2 or 4 inputs you have available.

This works for both RCA inputs and the speaker level inputs as well.

One thing I didn’t like however is how the mounting holes are spaced very closely to the plastic end panel “walls” if you will. It makes for a very tight space during installation and it’s easy to scratch the plastic with your tools when driving the mounting screws into place.

Checking out the bass remote

Closeup images of Rockville car amplifier bass remote

The optional bass remote includes a standard 6-conductor phone cable about 18 feet in length. The remote mounts near your dashboard and allows adjusting the subwoofer level any time you like. It’s very easy to use, easy to install, and a great feature I recommend.

No installation & test is complete without trying out the special features, right? I installed the included Rockville bass remote (cable is included) in my vehicle and got to work.

It’s very easy to use, although you don’t want to leave it just lying around. Personally I recommend at least using a good double-sided tape for a removable installation.

Ideally, however, you’ll use the screw mounting tabs provided. Unfortunately, installation accessories aren’t included with the bass remote. I can’t imagine why they’re not.

Setup and results

Image showing Rockville bass remote knob installed in a car

To use the bass remote, you’ll need to tweak the amp a bit after installation. You’ll need to increase the gain of the subwoofer channel so it’s very high when the bass remote is to its max setting, and so it’s at a normal level at zero.

It’s fun to use for that quick bass boost anytime while you’re driving and works well – I like it! It’s a lot easier than having to go into your head unit’s bass settings EVERY TIME you just want some extra bump for your favorite tunes.

How does the RXH-F5 sound? Real music and test tracks

Car amp test tracks playing snapshot

Some reference car audio test tracks I used for testing the amp and verifying sound quality. Top: Autosound 2000 Test CD #102. Bottom: A high-fidelity album from Mapleshade Music featuring unprocessed, excellent sound quality used in some high-end car audio demos.

Using my reference test CDs (as well as music I enjoy and I’m familiar with very well) I ran the amp through a series of tests to check some important characteristics:

  • Sound quality & clarity
  • Stereo imaging
  • Bass sound quality
  • Power output with real music

I do this because it’s important to be consistent when testing different audio components including amps. For example, if I were to change the way I tested the amp (change it from the previous installation) I could easily add 1 change that unfairly gives the wrong impression.

To be consistent, I use very high-quality audio tracks and I’m familiar with high-fidelity test tracks as a known good frame of reference.

Example of Spotify music tracks playing screenshot

Listening to your favorite everyday jams on Spotify (or whatever music source you like) is enjoyable and fun with the Rockville. Music is crisp, clear, and can really jam hard when you crank the volume. Bass-heavy songs like Ne-Yo’s Miss Independent come through clearly and with plenty of power. In fact I had a lot more power on tap when I needed it.

The music quality was great, with crisp, dynamic highs and punchy bass. While it’s a teeny-tiny bit less clear than my old-school reference amps, it’s still very good for the money. When I say it’s “good”, I really mean it sounds very good.

It’s surprisingly good for the price, surely due to the use of class A/B amp circuitry for the main channels. Class A/B amps have been popular for many, many years since they can offer great sound quality for lower cost.

Power and bass quality

With at least 500W RMS of power available to the subwoofer channel and well above 50W RMS to the main channels, power definitely isn’t a problem.

Driving a 4 ohm subwoofer is a pleasure and the bass absolutely is great. The power on tap is excellent and should be more than enough for most buyers. I got some great sounding bass with more power than I needed!

In fact don’t let the 50W RMS/channel CEA-2006 make you think you won’t have enough for great, loud music. In my experience, the uncertified RMS power ratings are more in line with what most people would find usable (in this case, around 100W RMS/channel).

Unfortunately, during more casual, low-volume listening I discovered a problem.

A problem with the Rockville RXH-F5’s design (noise)

Autosound 2000 CD #102 stereo test track playing

During amp testing when using test tracks played at a low volume (especially with vocals, like in this Autosound 2000 stereo imaging track) I found distortion was present in the main channels. It’s not noticeable at higher power levels – even moderately higher – but definitely a huge disappointment if you’re a sound quality enthusiast like me.

Unfortunately during testing, I discovered the amp’s design causes an odd type of distortion in the front & rear channels. It appears to be a design-related issue due to the class D power supply being added alongside the 4 channel amp sections.

I haven’t encountered this kind of problem for a long time. Using my test track from AutoSound 2000 it’s very easy to reproduce at low volumes with music tracks with vocals.

Class D amps use a much higher switching frequency for how they operate. It’s possible for class D amps to cause problems with nearby audio circuits because of this (high frequency designs often have to deal with electrical noise issues like interference as a result).

When testing the RXH-F5 during low volume with my reference test tracks I’m able to hear a slight kind of “sshhhhh” distortion that’s created in the musical signal. The type of distortion is one I’ve heard before and it’s caused by noise induced in the power supply and/or musical paths.

At moderate (normal) or higher volume it’s not noticeable at all – so it may not be a problem for many people. However, it tells me the amp hasn’t been fully vetted for low-noise operation and there’s more work to be done.

I’m an “audiophile” at heart and have very good hearing which is both a blessing and a curse. It’s easy for me to hear distortion when something’s not right like in this case.

It’s a shame, too, as I really wanted to be able to recommend this amp!

Confirming the problem

To have a fair and honest review, just in case the amp was a single defective model I called Rockville and exchanged it for a replacement.

Sadly, there’s no change and I’m easily able to reproduce it every time. It’s an inherent problem with the amp’s design and one that shouldn’t happen even in a budget amp. These days the company faces pretty solid competition out there.

As other 5 channel amps (both for car and home) don’t produce the same problem there’s no excuse for this.

I narrowed it down even further by eliminating all possible noise sources in my test system – it’s definitely an issue with the amp.

If you’re not picky like I am, you don’t have much to worry about. However, if you expect great clarity from your music and listen casually at lower volumes I think you’re going to be disappointed.

Owner’s manual quality

Image of the front cover of the Rockville Phenom car amp front cover

The owner’s manual is surprisingly good. I’ve seen many over the years and most are pretty weak when it comes to instructions, set up, and getting the most out of the amp.

This one’s better. While it covers several models in the amp family (which is fine, and typical for most amp manufacturers) the instructions apply equally to the main amps in the product family.

Where there are differences it’s made clear to avoid confusion.

Rockville RXA-F5 5 channel amp owners manual example 1

It’s easy to read and you’ll get clear instructions on how to wire up pretty much all speaker systems you could think of. For a 5 channel amp like this, the speaker systems used are pretty typical but you’ll get good, clear diagrams that help.

It’s also tri-mode capable, too, which is covered inside as well.

However, when using the speaker level input feature the harness adapter coloring isn’t listed in the manual for some reason. I’m not sure why that is, but it’s a pretty minor complaint.

Regardless, you’ll be able to connect speaker level inputs using the (+) and (-) symbols which are shown both in the manual and are printed on the amp itself – you just won’t find the connections listed by color but by position in the harness.

Special features that set it apart

Image of Rockville car amp manual clone function instructionsBandpass filter option: This one’s really unique and excellent for 3-way or even some bi-amped 2-way systems.

The rear channels offer not only a high pass filter (15Hz-1KHz), a low-pass filter (50Hz-3KHz), but also both can work together to provide a bandpass filter. Both the low and high pass adjustments will work the same in that case but will work together and you’ll adjust it as needed for the top and bottom cutoff frequencies.

Note: You won’t be able to use the amp to drive bass-only woofers from the front 2 channels as there’s no low-pass crossover for those – only full or high-pass.

For bi-amped custom speakers systems though, it’s not a problem. In that case, you’d use the high pass on channels 1 & 2 then the low pass option from channels 3 & 4.

Review score & summary

While it’s a good value, is well put-together, and has lots of great power to offer, I can’t get past the distortion issue. That shouldn’t happen – you won’t find the same problem from other similar 5 channel amps.

Unfortunately, after trying 2 identical amps and confirming the problem I can’t recommend the RXH-F5 if an affordable 5 channel amp with good sound quality is what you need.

Because I consider design-related noise problems unacceptable, I’ve taken a lot off of the sound quality & other rating factors in my review score below.

Note that my complaint might not be a problem for everyone – especially if you rarely listen to quiet music levels (for example if you’re a Jeep owner or someone who likes to crank it up a lot). In that case, you’ll never notice it and you’ll get plenty of amp for your money.

Sound Certified Rockville RXH-F5 review score summary imageSadly, I can’t recommend the Rockville RXH-F5 amp to buyers who care about sound quality at casual listening levels.

Hifonics Zeus ZXX-5000.5 5 channel amp product imageA better alternative with similar design, power, features, & price is the the Hifonics Zeus ZXX-5000.5 you can read more about at Amazon.

Overall
6/10
6/10
  • Overall quality - 5/10
    5/10
  • Sound quality - 2/10
    2/10
  • Power & performance - 7.5/10
    7.5/10
  • Installation ease - 7.5/10
    7.5/10
  • Features - 8/10
    8/10

A good performer and value sadly ruined by a noise problem affecting sound quality

I can’t recommend the RXH-F5 and that’s a shame – I REALLY wanted to like it as the sibling RXA-F1 is a good buy. However, there’s no excuse for noise at quiet listening levels due to design issues given the competition. The RXH-F5 is well put-together and offers plenty of power, however. It definitely offers a lot for the money – especially subwoofer power.

While other Phenom series amps I’ve tested have very good class A/B sound quality for the money, the addition of the 5th channel’s class D supply seems to cause noise issues/distortion during low volume. For some, it may not be a problem (especially at normal to high listening levels). Otherwise, check out the competition’s offerings instead if high fidelity sound is important to you.

Pros

  • Good build quality
  • Included bass remote works well
  • Nice appearance and finish
  • Good speaker terminal blocks
  • Speaker level inputs + auto-on sensing
  • Flexible input options (2/4/5 ch.)
  • Powerful subwoofer output
  • CEA-2006/continuous true power ratings
  • Good, clear owner’s manual
  • Bass boost EQ
  • Bandpass crossover option
  • Tri-mode capable
  • “Class G” power supply for more efficiency

Cons

  • Noise induced in front/rear channels noticeable at low volume
  • No speaker terminal wrenches included
  • No speaker input harness color diagram
  • Plastic mounting feet (vs metal)
  • Mounting hole spacing could be better
  • Occasional minor quality control issues
  • No low-pass filter on front channels
  • Bass boost limited to +12dB max vs +18 of others
  • No bridging label near terminals

The Only Alpine KTP-445U Review You’ll Need: A Tiny But Amazing 4 Channel Mini Amp

Alpine KTP-445U review featured image

Sometimes getting good sound can be really tough – most especially if you have limited space. And it’s a shame, too, because often that means you’ll have to do without.

My, how things have changed!

This little power pack of sound is a modern-day solution to a decades old problem – getting great sound in a tight space. In my Alpine KTP-445U review I’ll provide a detailed an honest review of this fantastic like amp.

Contents

Alpine KTP-445U basics

Image of Alpine KPA-445U amplifier angle viewIn case you haven’t noticed yet, I’m a big fan of this little guy – and very happy with what Alpine has come up with! I don’t normally expect much from miniaturized amplifiers, but in this case I can honestly say I’m impressed.

First off, we need to set the stage by understanding what this little amplifier is and isn’t. It is not an end-all solution for the best audio quality money can buy. Let’s be realistic – you cannot get “perfect sound” in an incredibly tiny package for less than $150.

When it comes to sound, there are always compromises that must be made. It’s important to have reasonable expectations. Any good engineer will tell you the same.

What to bear in mind…

Also, it’s important to remember that as I’ll be explaining below, this is a class D type of amplifier. Class D amps have several pros and cons to be aware of (which I cover in detail). It’s important to remember this when you compare it to other amplifiers you may be thinking about buying.

I’ll be reviewing it based on my extensive knowledge of the technology and the amp both as an engineer and an installer. Also, I’ll be very fair – and very detailed – when I make comparisons to bigger and more expensive amplifiers.

Behind the technology: understanding the KTP-445U amplifier design

In only the last several years class D audio amplifiers have become one of the hottest audio technologies in the audio world. This modern technology has improved greatly since the first class D amplifiers hit the market years ago. I’ve found that despite this many brands still leave a LOT to be desired. Unlike the KTP-445U I have been very disappointed by some I’ve tried.

What is a class D car amp?

Simply put, audio amplifiers are all based off on one or more basic “classes”, or categories that classify the type of design they use. Despite what you might see thanks to advertising, a car amplifier class always fits into one of 3.

These range from Class A (fantastic clarity and ultra-low noise specs, but expensive and a power hog) to Class A/B and now class D. For the most part, any other kind you might run across is just a variation of one of those. (For a “class T” amp is still a class D – that’s just marketing).

Class D amps were once only used for subs but now are mainstream

Until recent years, Class A/B amplifiers were the most common because they’re cost-effective, relatively simple in design, and don’t waste as much power as Class A designs do. Also A/B amps provide low distortion and high power levels for a good watt-per-dollar value.

Despite their good points, conventional (A/B) amplifiers waste a lot of electrical power which is turned into heat rather than power to drive speakers. Today’s amps are still somewhat bulky and heavy due to the large metal body needed to dissipate the heat created.

A class D car amp is a newer type of amplifier technology used to produce audio power more efficiently.

How do class D amps work?

Diagram how a class D switching amplifier worksA Class D amplifier works by “modulating” (chopping up) the incoming audio signal and switching the transistors used to amplify it on and off incredibly quickly. This results in a fantastically efficient design without huge amounts of power being turned into heat like designs from the old days!

Class D amplifiers are based on a switching circuit design approach. This means the design modulates – or transforms – the incoming audio signal by chopping it up into a series of on-and-off waveforms as the input signal is received.

This is used to switch power-conducting transistors on and off thousands or hundreds of thousands of times per second. Older audio amplifiers (like class A or class A/B) conduct electricity nearly all the time they’re on.

While A/B type amplifiers are about 50-65% efficient, Class D amplifiers can achieve an incredible 85-90% efficiency!

Because of this the amount of power being consumed by a Class D amp is greatly reduced – resulting in no need for a huge, heavy amplifier body or lots of heat being produced. This was a huge step forward in technology.

Fun fact: Some bare-bones miniature class D amps are smaller than a pack of cigarettes!

Additionally, electronic component sizes have evolved to make these amps smaller and smaller. The decades-old problem of “How can I fit an amplifier into a tiny space in my vehicle?” is now just a bad memory.

No longer do you just have to settle for a weak 15W per channel stereo head unit. You’re now able to get many times the sound in a package that’s far smaller than anything imagined possible only 10 years ago.

Alpine vs the competitors

Something you might not be aware of is that there’s a lot of junk out there. Many of today’s car amp brands are no longer selling unique designs of their own. Sadly, many amplifiers on the market today, including compact Class D designs, are rebadged models that share the same internal components and mediocre design and only have minor cosmetic differences on the outside.

Over the years, lower-end brands were bought out by larger companies and exist only for marketing purposes, not for quality.

I’ve even bought one of these competing amps for test purposes (perhaps one day I’ll do a write-up) and was very disappointed with the design & sound quality. Noise levels were unacceptable and upon examining it I realized quickly it was another low-end version of an “amp on a chip” design.

In the audio engineering world, this means shortcuts were taken at the expense of sound quality and performance.

Alpine has relied on its great engineering resources and the KTP-445U is different from the competition because it’s an original and fresh design. I was not disappointed to find it has the trademark Alpine quality and innovation that became my personal favorite over the years.

Also, Alpine doesn’t use misleading power ratings and specifications, unlike other brands. The power ratings and sound quality specifications I’ll go into below are realistic and honest.

This is important to me not just as an installer and an engineer, but because I need to be confident in anything I review and recommend. I know how it feels to spend your hard-earned money on products that disappoint.

KTP-445U features and specifications

Size

One of the biggest selling points is its size. The amp measures an amazingly compact 7 7/16″ x 1.5″ x 2.5″ (189 x 38.2 x 64.5 mm) in size. That’s smaller than pretty much any comparable amplifier available anywhere in the world today! I’m not kidding – I was expecting it to be much bigger. Basically all other high-quality Class D amplifiers below $200 today are at least 4 x the size of the Alpine.

mage of Alpine KPA-445U mini amplifier in my hand

Hard to believe how small it is. An amp with comparable power only a handful of years ago would have been 5 x times bigger. This one is small enough to hold in your hand!

Built-in high-pass crossovers

Originally I had expected the amp to be a “plain Jane” amp with NO features whatsoever, but it turned out I was wrong.

The amp actually, to my surprise, includes optional high-pass filters with selectable frequencies for the high-pass feature ( 60Hz, 80Hz, or 120Hz) to allow you to cut off speaker-distorting subwoofer bass if you like. Of course, you can always switch if off and run your speakers in “full range” mode if you like, but I normally prefer to block the lower bass frequencies.

My custom-installed 6.5″ speakers can’t handle the lower bass frequencies (they don’t do well below 50 Hz or so, so 60Hz is pretty close) so that’s very important to me.

High and low level inputs

Of course, I didn’t expect the Alpine to disappoint, but again they’ve done a great job in the design. The amp can work with both aftermarket head units via the or RCA inputs OR  speaker-level inputs from a factory stereo! In other words, you can use the KTP-445U to get a more powerful and better sound even if you have a factory-installed stereo in your vehicle.

The included color-coded wiring harness makes it easy and it’s a feature I’m sure a lot of buyers just like you will appreciate.

Quick tip: When adding an aftermarket amplifier to a factory system and connecting to speaker-level outputs, be sure to plan for getting some small-gauge speaker wire. Plan ahead for enough length to go from the speaker wiring connections to the amp (and back again, if powering factory speakers).

One thing I’ve learned in my years of car stereo installation experience is that the ability to connect to factory-installed stereos is a huge plus. The Alpine can be connected directly to factory speaker wiring in order to “tap off” and get a good audio signal to feed into the amp.

While not as good as being fed from an aftermarket head unit via the RCA inputs, it’s still a great option and in my experience, when done correctly, still sounds clean and there’s very little distortion or breaking up at higher volumes.

You can also disconnect the factory speakers once the KTP-445U is connected to avoid any distortion issues if that’s a concern for you.
Image of Alpine KPA-445U mini amplifier input harnessThe included signal input harness allows connecting both RCA (low-level) inputs or speaker-level inputs to the amplifier easily. Inputs are color-coded and explained clearly in the owner’s manual. A similar harness is used to connect to the output (to connect to speakers you’d like to use)

There are switches for audio controls on the bottom of the amp if you need to choose speaker level inputs or change crossover functions. As an added bonus, even if you’re using 4 speakers and only have a 2-channel input, the amp can provide a signal to all 4 outputs. You won’t have to buy a pair of RCA Y-adapters.

In order to bridge the amp, you’ll also need to set the 2/4 ch. input switch to 2 channel as well.

Image of Alpine KPA-445U mini amplifier control switches

Selectable option switches on the bottom of the amp allow you to adjust the crossover functions or split a stereo input into 4 channels. Also, this is where you must select the audio source before powering up the amp.

Front and rear gain controls

Image of Alpine KPA-445U mini amplifier controlsSeparate front and rear gain controls allow adjusting the amplification level depending upon the input signal strength you have. Speaker-level inputs, for example, might require turning it down, while RCA-level inputs may require boosting it a bit. It’s highly dependent upon what kind of stereo you have. In either case, it’s easy to adjust. The KTP-444U can accept up to 4V RCA inputs which are considered a “higher end” signal strength for aftermarket units.

Not too much I have to say here – the front and rear controls are easy to use and easy to adjust. Also, the gain controls “feel” good because good quality components (potentiometers, which are just adjustable resistors) are used on the circuit board. This means that when you adjust the gain levels it won’t change over time and will have a good “feel” when you turn them.

Power

The amp can deliver up to 45 watts per channel into both 4 or 2-Ohm speakers, which is surprising because most miniature amps in my experience cannot handle 2 Ohm speakers. This means you could add extra speakers in parallel (to a degree) if desired.

It’s important to understand that 45 watts isn’t enough for extreme sound levels or to drive large woofers if that’s your goal. This amp isn’t designed for that.

I’d estimated with a good set of efficient speakers, however, you can get close to around 100dB of clear sound before it begins to give out due to its limits. For most people with normal listening habits, it’s plenty of power and you need not worry.

For reference, it may be helpful to know that most in-dash car stereos can provide only around 15W-18W RMS or so per channel of usable power.

Sound quality

For me, sound quality is extremely important.

It seems like every little bit of irritating distortion or poor musical reproduction I’ve heard really grates my nerves.

I’m happy to report the KPT-445U has great good sound quality and is very impressive for a tiny amp! If you recall what I mentioned earlier, this is a Class D amplifier. The benefits of Class D amplifiers are a fantastic size, great efficiency, and a lower weight, but one of the drawbacks is reduced sound quality.

I can say with certainty (and don’t just trust me on this – check the multitudes of other happy reviews) that the sound quality is very good. Remember when I mentioned earlier about how I bought another brand of car amplifier and was disappointed?

It was because the noise levels (the noise I heard when no music was playing) was far too high compared to the many amplifiers I’ve installed and listened to over the years. Not so with Alpine – they’ve done a great job in minimizing noise.

I can say I was pleasantly surprised. I came into my review of the KTP-445U expecting an “ok” experience but was honestly very impressed with what Alpine has done.

Here’s an excerpt from the company themselves:

In order to ensure that Alpine sound quality is heard at your ears, we’ve created a platform that offers an unbelievably low noise floor, taking extra care to ensure a clean signal path, with no extraneous interference. The end result: The Power Pack boasts 1 Watt Signal-to-Noise Ratio of 82dB or better.Alpine Electronics

In my opinion, this says a lot. Why? Because it takes additional engineering time and manpower – in addition to planning – to make the effort to make better sound quality a design goal rather than a forgotten number on a spec sheet somewhere.

I’d much rather pay a bit more for something I know is designed right from the beginning and I know sounds great rather than just made to be “ok” and barely passable.

Quick tip: If you have to increase the gain level greatly it also increases your chance of hearing the base noise level in any amplifier, including this one. For best results, the amp should have a good, strong signal so that the gain can be turned down, resulting in the cleanest output possible.

And by the way, for you spec nerds like me, the specs on this little amp are great. According to the company, the Power Pack distortion actually decreases at higher frequencies, resulting in a clean and clear signal where your ear is most sensitive to distortion (less than 0.03% THD+N @ 1W, 1% THD+N at rated power).

Here are some of the most basic specifications you need to know:

Image of Alpine KTP-445U technical specifications

Note: the KTP-445U mini amp – despite its tiny size and simple design can drive 2 ohm speakers up to 45 watts each. I was honestly impressed and didn’t expect that.

Installation

Alpine KTP-445U under seat installation

Great for installation under seats and just about any small space you can think of.

The great thing about the size is that you can fit it in incredibly small spaces which were unheard of years ago. A great example is some of today’s vehicles in which there’s extremely tight space inside the dashboard, perhaps beside or behind the current stereo.

It’s a great solution to the most difficult installation problems which years ago would have required either a ton more money to be spent by customers or unfortunately cause some people to just “give up’ as there weren’t any other options.

It’s also a great fit for boats as well but you’d need to ensure it is protected against corrosion and exposure to the air and saltwater since it’s not marine rated. You can mount the tiny powerhouse by using the included zip cable ties to attach it to the nearest available wiring or mount it permanently using the included brackets and self-tapping screws.

Don’t forget that because of its light weight you could also use double-sided adhesive tape or Velcro if desired for convenience.

Note: Because it is so efficient and draws less electrical current than traditional amps, you won’t need to get a heavy-gauge wire installation kit and run extra wire. It’s possible to connect it to a nearby 12V supply from your car stereo, for example.

Accessories included with the KTP-445U

Image of Alpine KPA-445U included items

  • Mounting brackets (2)
  • Self-tapping screws (4)
  • Cable ties (2)
  • Required wiring harnesses

I would definitely suggest getting a few inexpensive items to make sure you’re better prepared for installation, such as:

  • A roll of speaker wire
  • 14 or 16 gauge power and negative wire for installations placed further way
  • Wire crimp connectors (“butt connectors”) and a crimp tool
  • A small bag of 6″ or 8″ zip wire tie

Bridging the amp

Need more power? Amazingly – and to my surprise – it’s not a problem with this amp.

Just switch the 2/4 channel input switch to the 2 ch. input mode. Then connect the output speaker wiring in bridged mode and you’re done!

You’ll have 90W RMS per channel of high-quality sound at your disposal. Honestly, I didn’t expect that for an amp so small, but once again the engineering quality made all the difference.

Just one more reason I’m impressed with it.

KTP-445U vs KTP-445A

Alpine KTP-445A image

The KTP-445A looks very similar to the KTP-445U. However, it’s designed specifically for Alpine head units 2005 and later, not for RCA or high-level inputs from others.

When shopping it’s important to be aware of the KTP-445A model as it can cause a bit of confusion and comes up in search results.

The KTP-445A is a model of the KTP-445U (where “U” stands for universal; “A” stands for Alpine head units) designed only to work with Alpine model car stereos. The wiring harnesses included don’t allow using RCA connectors and the standard speaker-level inputs.

Aside from that, both share the same basic design and performance.

There are a few drawbacks to know…

I would have liked to have an optional low-pass crossover feature in addition to the high pass design. Perhaps it was a cost-cutting or design compromise decision that had them remove it. I’m not sure.

I have somewhat mixed feelings regarding the location of the switches used to control sound options. They’re located on the bottom, whereas ideally, they’d be accessible from the side or top. But ultimately that’s a minor complaint.

Review score & summary

All in all, in my opinion, the KTP-445U is a wonderful little 4-channel amplifier with great sound quality. It’s truly a dream come true if you want great sound but have especially limited space.

It’s not for those who need extreme power and volume levels. You can’t drive subwoofers or very high-volume speaker systems with this amp, but what it does it does well!

Alpine KTP-445U review featured imageHead over to check out the current price and see the fantastic buyer reviews at Amazon.

Overall
8.8/10
8.8/10
  • Quality - 9.5/10
    9.5/10
  • Sound quality - 8.7/10
    8.7/10
  • Installation ease - 9.5/10
    9.5/10
  • Features - 7.5/10
    7.5/10

A well-designed and great sounding miniature car amplifier. One of the best compact amps I've seen.

Alpine has done it again with their approach to getting the most power and sound out of a tiny package. It’s a great upgrade for weak aftermarket or factory stereos. Thanks to its design it’s a great general-purpose 4-channel amp that can fit a wide variety of installation and audio system needs. You’re paying a few extra dollars for better sound and better design – and that’s exactly what you’ll get. You won’t be disappointed.

Pros

  • Amazingly small size!
  • Great sound, low distortion, and low noise design
  • Can handle 2 ohm speakers (4 channel mode)
  • 4 channel outputs
  • Bridgeable to 90W RMS x 2 channels
  • Selectable 2/4 channel input switch (no Y adapters required)
  • Speaker level inputs
  • Installation accessories included
  • Great power: 45W/channel
  • Built-in optional high-pass crossovers
  • Simple installation / no large wire required

Cons

  • No low-pass crossovers
  • Option switches are located on the bottom as opposed to top or sides
  • Could use more zip ties in package

Alpine MRV-F300 Full Review And Details: A Great Sounding 4 Channel Amp You Can Afford

Alpine MRV-F300 amp on top of its package

I’ve been a huge fan of Alpine products and have been for years. I love my 4 channel amps and I’ve been enjoying fantastic sound for many years now.

Having the flexibility that a 4 channel amp gives is great when it comes time to upgrade your system later.

When it comes down to it, you don’t need a super-expensive amplifier to enjoy great sound quality. However, you do need to pick one that’s a well-rounded great choice.

I’ll tell you all you might want to know about the MRV-F300 before buying. Read on to learn more.

Contents

Alpine MRV-F300 review – First impressions

It’s a great looking amp, very compact, and housed in a well-designed dark brushed metal chassis. It feels solid in the hand, but it’s still relatively lightweight compared to conventional older amps of the same power rating.

I have owned other amps in the past with the same power rating and they easily weighed 3 times as much as the MRV-F300 does! It measures just under 5 lbs (around 10 kgs).

Build quality is great, and I notice there aren’t huge gaps or misaligned parts like on cheaper amps of the same Class D technology. I’ve tested other type D amps before, and easily noticed they weren’t put together well or felt a bit flimsy and just didn’t feel solid. That’s not the case here.

Holding Alpine MRV-F300 amp in my hand

The amp looks great and the connectors are high-quality. You can make more reliable connection unlike lesser amps with standard screw terminals. Fit and finish are excellent, with no big gaps or sloppy assembly. The blue light on top glows when it is turned on (but not TOO bright, it’s not annoying). My opinion so far? NICE!

Connectors are very high quality and use hex-keyed screws to securely hold wiring connections. Connectors are clearly labeled, and take the guesswork out of bridging the amp if you choose to do so for more power.

The power connectors are circular inside and 8 gauge power wire will fit and is recommended for installation.

I really like what Alpine has done with the protective end caps it comes with – unlike amps in the past, they’re easy to get on and off.

They snap on and off! If you choose to mount it under a seat in your car or truck they’re great for protecting the wiring from shorts if you happen to have tools or coins lying around in your interior like I do at times.

Also, it just plain looks nice with them on!

By the way – upon opening the box you’ll find an Alpine Verification Certificate detailing the operation and performance of the amp you bought! Very nice.

MRV-F300 amplifier design and performance details

A huge advantage – compact size

Image of MRV-F300 amplifier top

The MRV-F300 has a cool glowing light on the top when powered to indicate it’s on. I love the compact size and honestly, I’m impressed with what they’ve fit into such a small package (Shown with end caps installed)

There’s a huge range of Class D car amps on the market today and most are pretty compact. The problem is that a well-designed car amp with decent power and GOOD quality sound requires a bigger circuit board and more parts – and that means a bigger size.

Alpine, for several decades, has been several steps ahead of the lesser brands. They use surface-mount component technology (SMT) to reduce the size required in order to make a smaller and better-sounding amplifier.

Measuring only 7 7/8″ W x 6.5″ D x 2 3/16″ H (200 x 165 x 55 mm) it’s crazy small and can fit in creative places that older amps could never even come close to fitting in!

That’s a huge advantage! You could even fit one amp under each seat in some cases for a great way to have a multi-amp system that thieves won’t see.

Class D amp technology

Class D amplifiers are one of the most recent developments in the audio world. Unlike conventional Class A/B designs (which most car audio amps still use to this day) that are around 50% efficient, a Class D amplifier uses ultra-fast switching technology to bring efficiency to near 90%!

This means since you are no longer wasting huge amounts of power (which turn into heat, by the way) the amp can be reduced greatly in size and doesn’t need a huge power supply internally.

However, as I mentioned at the beginning of my review, there’s something you need to know: Class D amps have higher “noise floors”, another name for the baseline noise or “hiss” level you hear when the gain is turned up.

Also, these types of amplifiers must be well-designed to ensure the technology use doesn’t modify your music signal (distortion) when amplified.

That’s what they’ve done, as Alpine uses their own engineering rather than repackage and relabel a lower-end audio amp as some competitors do.

The end result is the ability to provide up to:

  • 50W RMS per channel into a 4 ohm speaker x 4
  • 75W RMS per channel into a 2 ohm speaker x 4
  • 150 watts RMS x 2 bridged output at 4 ohms (4-ohm stable in bridged mode)

Performance and sound quality

Sound quality is just great as you’d expect from Alpine: music is full and clear, highs are bright and crisp, and bass is solid and easily drives speakers without giving out. It’s an excellent sounding amplifier and a winner! In the past, I had my doubts about Class D car amps (after having a few bad experiences) but the MRV-F300 has changed my mind. It’s that good.

Bass hits hard and has a great impact, just as you’ve come to enjoy from conventionally larger amplifiers.

If you’re planning to drive subwoofers with moderate power and volume (up to 150W each) you won’t be disappointed. If you need slamming bass, however, I’d consider the sibling MRV-M500, a mono amp with much more power available in the same size.

I have excellent hearing and based on my audio design & listening experience, I can definitely recommend this little powerhouse.

Alpine MRV-F300 4 channel amp end viewThe MRV-F300 features full range, low pass, or high pass crossover settings including 50-400Hz adjustable cutoff. A bass EQ (boost) feature is built-in too.

Audio controls

The crossover functions are easy to use. Controls and switches have a good, solid “feel” to them. One thing I’ve always noticed about Alpine Electronics is their products use good components that don’t feel sloppy when making adjustments. They also don’t change due to vibration over time after I’ve spent time & effort setting them up.

This amp is no different.

Note: the bass EQ boost is works only for the 3/4 channel pair when turned on. I’ve taken off points in my review score at the bottom as this feature in my opinion should be on 1/2 also.

One thing you need to know is that because it’s a Class D amp, by nature the noise level can be heard more when the gain is turned up higher. I definitely recommend adjusting the gain to a lower level that will still give adequate volume when the stereo is turned up high.

Alpine has done a great job in designing the amp, but it’s one of the trade-offs of this type of amp. Still though, it sounds wonderful and noise levels are basically imperceptible in most cases.

Additional features and installation

The great news is that it’s still easy to install – just like any other car amp as screw mounting is used to mount on tabs on each end of the amp (one pair of tabs on the control end and one pair on the power & speaker connection side.

It also works with speaker level inputs so it’s great for factory stereos too!

Alpine MRV-F300 installed under seat

The amp fits great under seats and can still leave room for speaker crossovers! Here’s an example of a custom install using the amp when space is limited.

Actually if needed, because of its light weight, in more difficult installations you could even use industrial strength Velcro or some type of reliable double-sided tape to mount it if necessary. The amp won’t heat up and cause the adhesive to lose strength, unlike amps in the past.

As I mentioned earlier it looks more professional to use it with the end caps snapped on, but I’ll leave that up to you to decide.

Quick tip: Because the amplifier’s mounting tabs face inward, it may be a bit hard to install under a seat. Be prepared to use a short screwdriver or even remove the seat to make your job easier when installing.

Accessories included

You’ll get the following inside the box:

  • 7.5″ Speaker-level input harness
  • 2 snap-on terminal covers
  • Four 3/4″ Self-tapping hex-head screws
  • Owner’s manual (English/ French/ Spanish)
  • Alpine Verification Certificate

…so you’ll need to remember to pick up whatever else you need before you start your installation, along with an amp wiring kit. I recommend picking up a good quality but great-priced 8 gauge wire kit like this one I found at Amazon.

It’s a lot less hassle to be prepared, and you sure don’t want to end up paying too much or having to run out for supplies while in the middle of your install work!

Specifications

For your convenience I’m including the specifications directly from the owner’s manual as well as details I’ve found myself.

Alpine MRV-F300 Specifications
  • 75W RMS x 4 (2Ω, 14.4V, ≤1% THD+N)
  • 50W RMS x 4 (4Ω, 14.4V, ≤1% THD+N)
  • 150W x 2 @ 4Ω
  • S/N ratio: >81dB @ 1W, >98dB @ rated power
  • Damping factor: >90
  • Front/rear adj. crossovers: Hi/low-pass, 50-500Hz, 12dB/oct.
  • 3/4 channel bass EQ feature (50Hz, +12dB)
  • High-level speaker inputs
  • Blue accent power-on light
  • Same power in a 40% smaller chassis
  • Evolution to Class D digital platform
  • Snap-on terminal covers for easy installation
  • Fuse: 40A
  • 1 year warranty
  • Compact size fits under seats
  • Dimensions: 8-1/4″W x 2-3/16″H x 7-15/16″D
  • Weight: 3.75 lbs (1.7kg)

You may have noticed that the signal-to-ratio ratio specified at 1W is lower than typical amplifiers. As I mentioned earlier, that’s an inherent design trait of Class D amps, but in practice with good speakers and the amp being sent a good signal level, it’s not really an issue.

I’m still pleased with the sound quality and wouldn’t recommend it if I didn’t feel you would be too.

Also note that the EQ boos is +12dB, in case you weren’t aware. That’s a very noticeable amount of bass increase.

Review score, pros & cons, and my final thoughts

I love this amp. For the money (it sells for a very reasonable price, usually somewhere close to $150 dollars or so) it’s a great buy.

As both an installer and a music lover I’d recommend it to nearly everyone except those who want extremely high signal-to-noise specs.

The MRV-F300 doesn’t disappoint as it’s a great performer – and definitely a great value, too!

Alpine MRV-F300 amplifier Editor's Choice image

Head over now to find out more and see why its one of the highest rated compact amps at Amazon.

Overall
8.7/10
8.7/10
  • Overall quality - 9/10
    9/10
  • Sound quality & performance - 8.7/10
    8.7/10
  • Installation ease - 9.2/10
    9.2/10
  • Features - 8/10
    8/10

A fantastic, great sounding 4 channel amp you'll be proud to own and can fit into small spaces

Is it small? It sure is! However, thanks to the superior Alpine design quality both music reproduction and power output are impressive for such a compact size. It’s a great performer musically and I love it. While many similarly priced class D amps by nature have a higher noise level than conventional Class A/B amps, Alpine has done a great job in minimizing noise.

Music is crisp, loud, and most of all enjoyable. This is an excellent amplifier for both aftermarket or factory stereos – with its small size it can fit safely away under seats or in storage areas. Factory systems gain the additional benefit of an auto-on sensing feature when the speaker level inputs are used. Not only that, but the included snap-on end caps round off a great-looking appearance nicely…and it’s priced close to the same as lower-quality competition models. Don’t pass this one up!

Pros

  • Excellent sound for a Class D amp
  • High efficiency – runs cool
  • 8 gauge wire terminals
  • Flexible crossovers built in
  • Bass boost switch
  • Small size fits in many small areas
  • Great looking finish & nice power-on light
  • End caps provided for clean install
  • Bridgeable for 150W RMS each channel pair
  • Speaker level inputs

Cons

  • Bass EQ boost only on channels 3/4
  • Normal Class D lower signal-to-noise ratio (improves as power output goes up)
  • Closed power terminals mean its difficult to fit 4 gauge wire
  • Mounting tabs face inward rather than outward – no option to change them
  • No remote knob available unlike the sibling MRV-M500
  • No 2/4 channel input switch