Hands-On Review & Test: Pioneer GM-D9605/GM-D9705 5 Channel Amplifiers

Looking for a 5 channel car amp to drive your whole system? You’re in luck: while you’ll run across a lot of bad buys out there, there are a few that are worth the money!

In my detailed review of the Pioneer GM-D9605/GM-D9705 5 channel amplifier, I’ll show you what I found from hands-on, real-world testing and why they’re good values and great-sounding amps you’ll love.

I’m really going to dig deep so read on to learn more!

UPDATE: The GM-D9605 has been discontinued and has been replaced by the nearly identical GM-D9705, so I’ve updated my review. I’ll report my hands-on review of the GM-D9605 model as it applies to both but I’ll be sure to cover the 9705 as well where needed.

Basics first – The GM-D9605 / GM-D9705 5 channel amp explained

Pioneer GM series class D car amplifiers with GM-D9605 and GM-D9705 comparisons

The Pioneer GM line of amplifiers consists of several different power levels and channel configurations. All are class D-type amplifiers and competitively priced. (Note that the GM-Dx6xx models are now renamed the GM-Dx7xx models). The GM-D9705 is the newer version of the GM-D9605, although they’re functionally the same (aside from different looks).

The GM-D9605/GM-D9705 is one of the company’s line of midrange priced amplifiers in the Classic GM series. GM amplifiers are all class D amps, meaning they using a modern high-efficiency design based on high-speed switching amplifier technology.

Note that the 9605 and 9705 models do have some slight internal differences, however, they’re functionally the same amp and use many of the same components.

The Pioneer GM series class D car amp family

Class D amplifiers are a relatively modern approach to car audio and offer several benefits.

The biggest advantages are reduced size and cost, higher power efficiency (less power wasted as heat), and running cooler during high power output.

Much like other 5 channel amps, the GM-D9605/9705 offers flexible use that’s installation-friendly. You can run an entire great-sounding system from a single amp that can fit under a car or truck seat.

GM-D9605/9705 Amp System Options

Several configurations are possible:

  • 4 main channels (full-range front & rear) + 1 subwoofer output (bass only)
  • 3 main channels (2 standard + 1 bridged) + 1 subwoofer
  • 2 main channels (2 bridged for more power) + 1 subwoofer

In all cases, you can drive rear speakers even if you only have 1 pair of RCA outputs as a 2/4 channel input switch is provided.

It’s a great feature and saves you the cost of Y adapters and really expands your options.

Until fairly recently 5 channel amps (especially at the power level of the GM-D9605/9705) were some of the largest amps sold. They were fairly tough at times to fit into a vehicle.

Thankfully the class D design makes it possible to get the same power and flexibility in a smaller size and with less power draw, too.

Signal input options

The great news is that it’s very flexible not only in the number of channels available but it’s great for factory stereos as well.  There’s a handy 4-channel speaker level connection provided (wiring harness included).

When using a stereo without subwoofer outputs, you can use the subwoofer input switch set to “A/B” to derive low-pass bass from them instead.

Either way, it’s great for nearly any system you can dream up for your vehicle in my opinion.

Unboxing and first impressions

Pioneer GM-D9605 review unboxing front image

My Pioneer 5 channel amp (GM-D9605) arrived safe and sound. The amp is well-packaged with great foam inserts everything is nicely bagged and tucked inside. I was expecting good things from Pioneer and I’m happy to say I wasn’t disappointed!

Finally, it came! As a Pioneer car audio owner & product installer in the past, I had high expectations for the Pioneer 5 channel amp. This was a wonderful opportunity to test their modern car amp design.

My amp arrived well-packaged with a smart, professional design just like you’d expect from a leader in the car stereo industry. Right away I got a good feeling.

Everything was put together nicely and the included accessories were tucked away neatly inside.

What’s in the box?

Pioneer GM-D9605 image of included items

Pictured: Everything included with the Pioneer GM-D9605. Aside from an amp wiring kit and installation-specific accessories, you’ll have everything you need to install the amp itself and mount it. Note: I do recommend some double-sided tape for the bass remote if you’d like to avoid screw holes when mounting.

After opening up the box and removing the amp here’s what you’ll find inside:

  • Owner’s manual and warranty info
  • Bass remote knob assembly and cable (16 ft long) + mounting screws
  • Amp mounting screws, black, 1/2″
  • Speaker and power terminal Allen (hex) wrenches
  • Front/rear speaker level input harness

Note that you’ll need a good amp wiring kit like in my amp kit buying guide to make your installation easier & with great results.

It’s especially important to have good quality wire and the little bits and pieces that make the work much less of a hassle!

Pioneer GM series car amplifier high level input harness image

For factory stereos or aftermarket stereos with no RCA jacks, you’re covered! The included speaker-level (“high level”) wiring harness connects to the speaker wiring from your stereo and plugs into the amp. Industry-standard color codes are used to make wiring clear.

The included speaker level input harness is very compact and easy to understand. Not only clearly spelled out in the owner’s manual (which is very nice, by the way) but also it uses industry standard colors.

Positive and negative wiring is marked by the use of 1 striped wire for each pair of input wires for a total of 8 wires (4 inputs for both front and rear options).

For my test setup, the included hardware (screws, hex wrenches, and remote cable) worked great and I had no complaints at all.

Build quality and close-up evaluation

Pioneer GM-D9605 top view closeup image

The GM-D9605 is a great-looking amp that has a nice glossy finish on top. The sides, edges, and surrounding areas feature a lovely matte black style. Overall, it’s a great design and everything is put together nicely.

As I like to do, I gave the amp a close-up and thorough inspection to check build quality, fit and finish, and to find any defects in assembly.

I’m happy to say the build quality is great, the cosmetic looks are excellent, and I found no defects to be aware of.

I especially like how it looks on top: somewhat resembling a carbon fiber material. There’s a glossy coating over a metal pattern designed into the single-piece heavy-duty metal shell.

The amp feels great in the hand and is definitely not a lightweight by any means! When you pick up the GM-D9605, at about 7lbs in weight, you can quickly tell it’s well-made and designed for handling some big power output.

Front and rear panel details

Pioneer GM-D9605 closeup image of front and rear

Front and rear view of the amp’s controls and wiring terminals. A very compact amp for its power class at only 12.4 x 2 x 7.87″ in size, the company had to fit a lot into a small area. Controls are well laid-out and work well in my experience. The wiring terminals are interesting (I’ll cover that later) but very high-quality, too.

The front and rear panels, like other class D amplifiers, have to fit in a smaller size than the amps of days gone by. Because of this, you’ll often find similar amps have controls and labels very close together.

However, no complaints here. The crossover controls, bass remote jack, RCA input jacks, and much more are nicely done. The lithography (label printing) is nice and clear, although the topmost labels are harder to see at times.

I checked the switches and dial controls and everything felt nice and tight – no signs of cheap, low-quality parts being used.

Wiring terminals (and my thoughts on them)

Pioneer GM-D9605 wiring terminals close up image

Close up: the wiring terminals where you’ll connect power, ground, remote, and speaker wiring. They’re very high quality and offer an excellent, reliable connection as I discovered during installation. Note, however, that the openings are angled downward slightly.

Similarly, I can say the same for the wiring terminals. Unlike cheaper amps, Pioneer uses a high-quality machined metal wiring block in the design.

Within each wire terminal is a single machine screw that uses one of the 2 included hex wrenches. You’ll use the included metal wrenches to tighten down the screws and secure wiring.

Don’t sweat it, though – you can tighten them down firmly but there’s no need to get them super tight. Once tightened down firmly by hand the wire isn’t going anywhere!

A note on the terminals

There is one little detail that caught my attention, however. The wiring terminal openings are angled downward and not perfectly horizontal.

In practice, it wasn’t a problem for me, but I can see how some people might find it a bit harder to insert wiring during installation.

After installation using proper lighting (yes, I installed it outside at night!) the job went fine and I can’t really complain much.

The GM-D9605/9705 amp guts revealed! Checking out the electronics

Pioneer GM-D9605 internal components and circuit board images

To be 100% sure about the build and design quality I opened up the amp. Inside is a smartly designed, well laid-out printed circuit board (PCB) with miniaturized components and good build quality. There’s a very beefy power transformer. Components are high-quality and the assembly is well done. The 9705’s internal components are very similar as well (not shown)

I wasn’t kidding earlier when I mentioned I’d be digging deep into the details! One great way to really find out about the quality of an amp is to open it up and give it a more thorough look.

As you can see above in the images, Pioneer uses miniaturized surface mount technology (SMT) components to keep circuit space to a minimum and optimize sound quality.

Additionally, I noticed the capacitors and transformers that make up the power supply are into place for added durability and vibration resistance. That’s something you don’t always see, sadly.

It’s important to remember that the GM-D9605 & D9705 sit in a “sweet spot” in terms of cost vs quality & performance: not cheap, but not too expensive, either.

What I found inside reflects that as well: a well-made, well laid-out circuit board with good fit and great assembly quality.


Pioneer GM-D9605/D9705 Specifications
  • Channels: 5 (4 full-range + 1 subwoofer channel)
  • Amp class type: class FD (custom class D design)
  • Signal inputs: 6 RCA inputs (4 front/rear “A/B” + 2 subwoofer) + 4 ch. high-level inputs
  • 2/4 RCA input switch
  • Subwoofer: Dedicated inputs or derived from main channels
  • Bass boost level: 0 – 18dB, adjustable
  • High-level input sensing auto-on feature
  • Crossovers:
    A/B ch.: High/low pass, -12dB/Oct, 40-500Hz adjustable
    Subw.: Low pass, -12dB/-24dB/Oct selectable, 40-500Hz adjustable
    Bass boost center freq.: 50Hz
  • CEA-2006 continuous RMS power ratings:
    75W x 4 + 350W x 1 @ 4 ohms
    100W x 4 + 600W x 1 @ 2 ohms
    Bridged: 200W x 2 @ 4 ohms (Front/rear ch.)
  • Speaker terminals: Channels A, B (front, rear) stereo + single subwoofer out
  • Freq. response (A/B): 10Hz ~ 50kHz (+0dB, -3dB)
  • Freq. response (sub): 10Hz ~ 500Hz (+0dB, -3dB)
  • Total Harmonic Distortion (THD): A/B CH: <0.05% (1kHz) / SUB CH: <0.05% (100Hz)
  • Signal-to-Noise (SNR): > 94dB
  • Fuse Rating: 30A x 3
  • Includes bass remote knob + 6 wire, 6 position telephone cable
  • Includes mounting screws for amp, remote, and hex wrenches for terminals
  • Wiring terminal type: insulated high current hex screw solid block machined
  • Owner’s manual with detailed instructions
  • Protection circuit for shorts, thermal overload, low voltage
  • Warranty: 1 year
  • Size: 12.4 x 2 x 7.87 ” (31.5 x 5 x 20 cm)
  • Weight: 7lbs 2 oz (3.2kgs)

If you’re not familiar with car amplifier ratings, it’s important to understand that power ratings in the mobile electronics industry are a huge source of confusion and are often used to mislead buyers.

CEA-2006 Compliant logo

Fortunately, the industry established a good (although, voluntary) set of standards in the 2000s which reputable manufacturers use to assure you of what you’re getting. Amplifiers sold today that provide Consumer Electronics Association 2006 (CEA-2006) power specs guarantee the amp will perform as advertised.

Like several other top car audio companies, Pioneer’s GM line of amps is no different.

The GM-D9605/D9705’s CEA-2006 compliant power ratings are guaranteed correct. In fact, the GM line of amps has actually be proven to exceed their ratings by a small margin!

My hands-on experience reflects this as well. I can definitely tell you that there’s NO shortage of power with this guy!

My test setup and installation

Pioneer GM-D9605 review test setup diagram

A diagram showing the general setup used for testing the Pioneer 5 channel amplifier. I replaced my high-spec reference amplifiers and tuned my system to correct any problematic frequency response behavior in order to best test the amp’s sound performance.

Now comes the part where things get real! How would the Pioneer stand up against my class A/B reference amps that are 40% bigger in size?

And is the GM-D9605 really a great value like I thought, or a just another average, mid-tier amp?

It’s time to find out!

Installing the GM-D9605

Pioneer GM-D9605 review test amp rack image

For my test setup I at times enjoy real-world use of an amp using an amp rack and everyday listening. Here’s the Pioneer amplifier mounted on an amp rack for a reliable, neat installation.

Using the same method found in my guide on how to make your own car amp rack, I set up my test installation and installed the amp in my test car.

One thing’s for sure – if I’m going to give an amp a fair test the installation quality is definitely important. Professional installation with neat wiring and everything secured in place isn’t just good-looking but is a requirement for reliability.

Setup and wiring connections

Pioneer GM-D9605 gain setup during installation example

Getting the amp gain and crossover settings ready during installation. The controls work well and are easy to use. Additionally, what helps set the amp apart from others is how the gain level control is labeled with “Normal”, “0.5V”, and “6V”, giving you a better idea of the general range & position the dial should be at.

I set up the baseline gain, crossover, and other controls adjustments (like for the subwoofer) when mounting the amp rack into place. In my cases, the high-pass crossovers weren’t needed so I left them set to flat (off).

This allows an unrestricted audio range as my Alpine digital signal processor (DSP)/EQ already provides filtering.

For the subwoofer control, I started with an initial gain setting somewhat bit higher as from experience in my setup it’s needed. Normally I’ll fine-tailor them later once the system is powered and working ok.

Pioneer GM-D9605 wiring connection installation example

Connecting power & speaker wiring to the amp. All went well as planned, even though the downward-angled terminal openings are a bit new to me. In the end, the terminals work very well and you’ll get a nice, tight, and great-conducting connection!

Finishing it up, I wired up the amp, carefully inserting the power and speaker wiring as these types of terminals are a bit new to me. The slightly down angled openings turned out to not really be an issue at all.

They worked well, and despite the wiring openings being less visible immediately, the design is actually quite good. Using the hand wrenches supplied in the box I carefully tightened the connections to avoid stripping or any other issues.

Note: strongly recommend against using a cordless drill or screwdriver when working with terminals like this. It’s ease to overpower the screw and strip out the inset shape, leaving them rounded out and much hard to work with.

My advice is to always do delicate or fine fasteners by hand.

I also sometimes do things by hand to check the “feel” of parts – poorly designed or manufactured connections sometimes show themselves when they feel cheap or loose. That wasn’t the case here.

The connections were excellent and it only took a few moments for each connection point to get a highly secure & tight clamp.

System EQ setup

Alpine PXA-H800 DSP/EQ in-car test setup and adjustment example images

To keep things “fair” during test evaluation I made sure to remove any nasty sound peaks or dips that would give my ears a false impression about the Pioneer amp. Using my calibrated microphone and real-time analyzer (RTA) software I smoothed out any problem areas. This lets me test the amp on a “level playing field.”

Of course, it’s never a good idea to compare apples to oranges, so to speak. After installation, I used my real time analyzer (RTA) software and calibrated microphone for equalization adjustments.

This lets me do critical listening of the amp’s sound reproduction by removing any nasty peaks or dips in the sound system’s response that might influence what my ears hear.

Firing up the laptop I got to work taming any areas by adjusting my Alpine DSP/equalizer processor’s 31 bands as needed for the main channels and the subwoofer output.

More about the bass remote

Pioneer GM-D9605 bass remote installation example

The bass remote installed using double-sided tape for avoiding drill screw holes for test purposes. I do recommend the screws if you’re ok with permanent holes, but for many people using an alcohol prep pad and then sticking on adhesive tape is a great option.

The bass remote is pretty easy to install and works great, although the knob is a bit small. However, it lets you easily dial in as much slamming bass as you like with the 0-18dB boost provided.

Basically, it’s a very small assembly with a 6 pin, 6 conductor jack on the rear that installs by connecting the provided black telephone cable. At 16 ft 5″ (5m) in length, it works well in most vehicles.

Alternatively, you can also pick up a longer cable of the same type if the original isn’t long enough for you.

Close up images of Pioneer GM series car amp bass remote details

Closeup of the bass remote, a small dial control that uses a 6 pin phone cable to allow you to boost the subwoofer output’s level any time. It works great and is a really handy (and fun) way to get more enjoyment out of your music.

I especially like that it’s included at no extra charge, as some competitors charge up to $25-$30 for theirs when sold separately.

How does it 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

The result? The GM-D9605 had spot-on imaging in my test setup as with my class A/B reference amps. No problems there! The left, center, and right placement of the instruments was exactly spot-on.

Example of Spotify music tracks playing screenshot

Listening to everyday music like your favorite tracks on Spotify (or whatever music source you like!) is enjoyable and fun with the Pioneer. Music is crisp, clear, and can really jam hard when you crank the volume. Clear, well-recorded songs like Ne-Yo’s Miss Independent come through great and have an excellent low-end bass sound!

The music sound quality was great, with crisp, dynamic highs and punchy bass. While there is a tiny bit less detail than my original (and much less efficient) reference amplifiers, that’s to be expected of a midrange class D amp.

It’s important to understand that unless you’re spending absolute top-dollar money for a higher-end amp like the JL Audio XD700/5v2 it’s a compromise that comes with an amp in this price range.

I have to say, however, that unless you’re one of the pickiest audiophile listeners, you’ll enjoy it. It’s a very clear, musical amp that has a ton of power just waiting to perform.

Cranking up the bass anytime you like thanks to the bass remote is fun! It’s a great little feature to have and I definitely recommend installing it. The knob is a bit small so I would have liked a slightly larger size to make it even more convenient to use.

I have to say, however, that unless you’re one of the pickiest audiophile listeners, you’ll enjoy it. It’s a very clear, musical amp that has a ton of power just waiting to perform.

Should you choose not to install the bass remote, however, be aware that there’s no bass boost feature on the control panel. In that case, you’ll have to live without a boost adjustment on the amp.

Fun music, mucho bass!

All in all, I enjoyed the sparkling, crisp highs, and especially the subwoofer output. This is an amp that can really put out some serious power when you’re jamming hard.

It’s hard to believe how much power you get from such a little size: 350W x 1 at 4 ohms and 600W at 2 ohms (the minimum Ohms/subwoofer rating supported).

Never was there a problem with running out of power – this little amp is excellent for systems using subs and I got bass that hits hard any time I wanted it.

GM-D9065 vs GM-D9705: Are there any differences?

Pioneer GM-D9605 vs GM-D9705 5 channel car amp comparison image

While you might be a bit nervous about the possible differences, you’re in luck – there aren’t any. The 2 models are different only in the outside of the amplifier. The internal design, connectors, inputs & controls, and all specs are the same.

There are only 2 very small differences between the two models. They’re functionally the same amp inside.

As often happens in the industry both models are almost identical aside from a new look:

  • Internal components, power, sound quality, and specs are the same
  • The same bass remote is included with the D9705 as pictured with the D9605
  • Both the input connectors, controls, and wiring terminals are exactly the same

Some minor differences I found are the following:

  • The GM-D9605 has a glossy finish over a simulated carbon fiber pattern; the GM-D9705 has a slightly shorter top with a machined metal finish
  • The GM-D9605’s screw mount feet are a bit easier to access than the GM-D9705, giving a slight advantage at installation time
  • The 9705 has the same general internal electronics and many of the same components, but a slightly different circuit board (same power & performance specifications)

Other than that, there’s nothing worth mentioning.

Review summary – Should you get one?

After testing for some time and putting it through its paces, I have to say I’m very happy with the quality, sound, and power I got for the money. It’s a definite YES!

There are a lot of choices out there when it comes to 5 channel amps but the Pioneer GM-D9605/D9705 delivers some of the best all-around performance and value you’ll find anywhere. It’s an excellent choice for all but the most discriminating listener.

As an installer and audio fanatic, I really like how flexible it is, too. The features really let you tailor your sound a lot. The included bass remote adds that extra bit of fun when it comes time to crank up the bass.

While they’re almost the same aside from minor differences, I prefer the more modern style of the GM-D9705 over the 9605 model. I wouldn’t hesitate to recommend the 9605 if you like carbon fiber accents though.
Pioneer GM-D9605 GM-D9705 Editor's Choice product review image

These are affordable, solid amps that have all the power most people could want – with the sound quality that you usually expect from more expensive amps. Even better, they can fit under a seat since they’re so compact.

Head over now to find out why the GM-D9065 and GM-D9705 are some of the best-rated car amps sold today at Amazon.

  • Overall quality - 9.5/10
  • Sound quality - 8.8/10
  • Power & performance - 9.2/10
  • Installation ease - 8.9/10
  • Features - 9/10

Mid-priced 5 channel amps that really deliver, the Pioneer GM-D9605 & GM-D9705 offer an excellent - and affordable - way to power a whole system

While competitively priced, the GM-D9605/D9705 delivers serious power at 2 and 4 ohms. Bass fans won’t be disappointed, and neither will you if you want dynamic, crisp sound with plenty of power. Full-range sound is excellent, although it can’t match the detail level of competitors at twice the price. Bass is powerful, punchy, and enjoyable.

As a full-range system amp, it’s great for music and offers nice flexibility from an efficient & compact class D package. Quality is excellent, and the bass remote makes jamming hard even more fun. Try one on for size and you’ll love it too!


  • Good sound quality and clarity
  • Excellent power/CEA-2006 proven ratings
  • Bass remote & cable included
  • Bass boost feature works well
  • Great crossover flexibility
  • 2/4 ch front/rear input switch
  • High-level inputs w/ harness
  • Auto-sensing remote feature for high-level inputs
  • Bass signal input from RCA or derived from main chs.
  • Solid machined wiring terminals work well
  • Great looks
  • 0-18dB bass boost range
  • 12/24dB/Oct. sub crossover switch
  • Protection circuitry
  • Runs cool during use
  • Clear, detailed owner’s manual


  • No accent lighting on logo or body
  • Bass boost feature only works with remote
  • No separate protection indicator lights
  • Speaker and power terminals angled down slightly
  • Sound quality can’t match higher priced amps
  • 16′ 5″ (5m) remote cable may be short for some vehicles
  • Bass remote knob is small
  • No double-sided tape included
  • Top adjustment labels are harder to see

Your comments are welcome!

  1. Hi Marty
    i need some help with setting the knobs of Gm 9605
    4 channel mode
    a clear picture would do and ill be very grateful

  2. Marty, I really enjoy your test reviews. The “amp dyno tests” on Youtube have become very popular, mainly because of how many amps offered by “non-Tier 1″ manufacturers often list their RMS outputs at twice or more than what they actually produce.

    I much prefer your reviews which are based on actual listening sessions. Car audio amplifiers are designed to reproduce music, not just power. I grew up listening to music from the 70s and 80s, mostly pop, rock and progressive, and most of that music is intricate and will reveal distortion and coloration much more than most of today’s music.

    I have an 18 lb circa 2012 Cadence F100-5 Class AB amp in my boat that really sounds good through the four MB Quart 6.5″ components and dual 10” Polk DB sealed sub box. Surprisingly, it’s idle current (with no music) is less than 1 amp, compared to a Polk PA-D200.2 Class D 2-channel amp that idles at 1.5 amps. At low volumes, that beastly Cadence amp will draw less power than the Polk, which means more listening time at anchor before the battery charge gets low.

    I’m sure when cranked, the Cadence current draw will surpass the Polk. Anyway, I do very much appreciate the time and effort that you put into your reviews — and keep up the great work!!

    • Jordan, thank you so much for your kind comment and taking the time to post it!

      You make some great points. In once recent case, I was disappointed with a different brand 5-channel amp and discovered that unfortunately it produces undesirable noise at low levels, leading me to give it a low score. That’s something I wouldn’t know without a real listening test.

      (Wasn’t an issue with the Pioneer models, by the way – they’re pretty good).

      The points about boat battery life are really good, too, and that’s a good reminder for me. It’s interesting to hear the Cadence’s current draw is lower at idle. Not quite what I expected!

      All the best and I appreciate you dropping by. I’ll keep working on more good posts like these. :)

    • Saludos marty

      Yo he encontrado una diferencia entre ambos amplificadores en la entrada de alta…
      El piooner gm-d9705 trae conexión para 8 cables, 2 por canal, y el gm-d9605 tiene conexion para 10 cables. Yo quiero conectar mi estereo de agencia que no trae salida rca, y me decidi por el gm-d9705 por las entradas de alta, me llegará en unos dias.
      Lo que quiero preguntarle es si me debo de preocupar por posibles parásitos o ruidos derivados de este tipo de conexión.
      Mi bateria se encuentra en el maletero, con lo que los cables de corriente no se cruzaran con los de conexión por alta.
      Aun así me preocupa.

      [Greetings Marty

      I have found a difference between both amplifiers in the high input …
      The Pioneer GM-D9705 has a connection for 8 cables, 2 per channel, and the GM-D9605 has a connection for 10 cables. I want to connect my stereo that does not have rca output, and I decided on the gm-d9705 for the high inputs, it will arrive in a few days. What I want to ask you is if I should worry about possible parasites or noise derived from this type of connection. My battery is in the trunk, so that the power cables will not cross with the high connection cables.
      Still it worries me.

      • Hola Juanjo. Perdon como no habla espanol perfectamente, pero estoy tratando.

        En ambos casos, el amplificador tiene hasta 6 entradas, – o – las entradas del altavoz.

        Normalmente no tendrá problemas con el ruido al usar las entradas de los altavoces. Es muy rara vez me ha sucedido eso. Por lo general, puede producirse ruido (ruido del alternador, “alternator whine” en ingles) cuando se utilizan los cables RCA.

        Si se encuentra con un problema de ruido con las entradas de los altavoces, puedes usar un adaptador RCA de buena calidad en el caso.


        [In both cases the amp has up to 6 inputs – or – the speaker inputs.

        Normally you will not have problems with noise when using the speaker inputs. I’ve very rarely had that happen. Usually noise (alternator whine) can happen when using the RCA cables.

        If you run into a noise problem with the speaker inputs you could always use a good quality RCA adapter in case.


  3. Hey Marty,
    Great review! This helped me decide to buy this, it should arrive in a few days. I installed a system a long time ago, it had an active sub so I didn’t have to worry about matching ohms and wattages, I consider myself pretty new to all this. I will be using this amp to push four 4 ohm full range speakers and a sub, I will just be using the full range speakers I have, however I am looking for a subwoofer and am deciding if I should get a 2 ohm sub, or a 4 ohm sub. This amp has an output of between 2 ohms and 8 ohms, but how does this work? Is there a way to select 2 ohms or 4 ohms on the amp, or do I simply hook up 2, 4, or ohm speaker(s), and the amp pushes out the wattage depending on the wattage? Also, because my full range speakers are 4 ohms, does my sub also have to be 4 ohms, or does it matter? Thanks in advance! Also, If you have any subwoofer suggestions that won’t break the bank (> $200 with box) I would appreciate it. Thanks!

    • Hi Ryan, how are you? I’m sure you’ll enjoy the amp.

      – You don’t have to select the subwoofer Ohms, just connect yours that’s all
      – It’s ok to have different impedance (Ohms) speakers hooked up to the amp. It doesn’t affect the others as the channels are separate.
      – The Ohms rating works by how the amplifier is designed. It can handle a certain amount of current & power demands (speaker load) which determines the Ohms rating you can use.

      So really as long as you meet the minimum Ohms rating of an amp when connecting a speaker you don’t have to do anything else. It’s just a guideline of what can be used with the amp.

      You might consider a pair of 12″ subwoofers in a sealed or vented enclosure like these 12″ MTX Terminator subwoofers preloaded in a box. (Basically just depends on your needs & how much room you have etc.)


  4. Hello, I have a question about the “bass boost” knob. Is it actually a bass boost, or like the Alpine does it control the amps gain? For example, when I tuned my Alpine mono block I did so with the bass knob turned all the way up, as the manufacture informed me it was truly a gain knob. Thanks, I hope my question makes sence.

    • Hi there Jason. That’s a good question!

      It depends on the design of the particular amp in question, but generally it’s a gain just for the subwoofer function. A bass boost usually multiplies the bass signal but only around one center frequency (very specific range of bass sound) like 50Hz or so.

      Hopefully that helps.

    • Actually the bass boost knob on the 9705 is different than the 9605. 9605 uses the standard RJ11 6 pin connector as you have pictured but the 9705 uses an RJ9 4 pin connector which is a little more difficult to find in the length needed if you damage the one that came with it so be careful

  5. Thanks Marty, one more question. I’m hooking up the gm-d9705 to an older pioneer amp that only has two RCA outputs, a front and a rear/sub. I called pioneer and the guys ssid the switches wouldnt help me. My plan is to split the front channel input with Y rca’s into the a and b channels then run rca’s from the rear/sub to the sub input. I’m aware I’ll loose the fader, the other option would be to split the rear/sub output between channel b and the sub input. What do you think? Thanks.

    • Hi there. You won’t need to do any of that. You can just set the front channel input switch to “2” and the subwoofer input switch control to “A/B”, and you’ll get a signal to all 5 channels.

      Fortunately the Pioneer (like some other 5 channel amps) is pretty flexible and provides a way to use only a 2 ch. input.

      You won’t technically have a front/rear fader control but at least you can use the rear gain to decrease the rear speaker volume like you would normally set it to with a fader (so it won’t be overriding the front channels)

      For example, this setup is shown in the GM-D9705 manual under “Connecting the units” & “CH-A input (Two-channel input).”

    • If they’re regular front & rear RCA outputs, you’ll use the “CH-A CH-B input (Four-channel input)” setup, so you’ll derive the subwoofer signal from the front/rear (A/B) inputs.

      If the rear RCAs are subwoofer outputs (or can be set to be a subwoofer output, as some head units can do) then yes you’d use the “CH-A CH-SW” setup.

    • What’s up Marty!? First off love Soundcertified. Now, I’ve swapped out a number of factory HU’s for aftermarket & same for the speakers too but installing an amp, I’m new to. I bought the Pioneer GM-D9705 with Knukonceptz 4 gauge amp wire kit. The kit came with 1 speaker wire, that being for the sub. I KNOW THE WIRE KIT I BOUGHT IS COMPLETE FOR MY AMP & SUB BUT IS IT ENOUGH TO CONNECT 4 SPEAKERS + SUB FROM AFTERMARKET HU? CAN I JUST USE RCA’S FROM MY HU TO AMP OR DO I NEED TO PURCHASE MORE SPEAKER WIRE?? IF SO, DO I HAVE TO USE BOTH RCA + SPEAKER WIRE?
      I apologize for the few questions one after the other but they relate to my one issue how to hook up my 4 speakers (2-6×9’s) (2-6 1/2) from aftermarket radio to amp.
      I’m pretty sure you reviewed the Knukonceptz Kit, so the kit is sweet & complete.
      Thank you Marty!
      Your doing a great thing here for people!!

      • Hello Dante and thanks for the nice comments. Glad to hear you got a good kit. You’ll be glad you did. :)

        1. You will need to get more speaker wire. The 20′ length included in the kit isn’t enough for much except the subwoofer.

        I recommend getting two 50 foot rolls or one 100 ft. roll so you’ll have enough. It doesn’t have to be expensive wire, just decent quality, typically 18 ga works great.

        For example, let’s say you installed it in the back of a car and ran speaker wire to the dash from the amp, 16 ft being a typical length. That’s 16 ft. x 4 = 64 ft. used. So you can see how quickly it gets used up for an installation.

        It’s always better to have a bit extra than not enough!

        2. For the RCA cables, it depends on your head unit. If it has front and rear RCA outs, you’ll need another pair, and you can use a front/rear fader. If it has a 3rd set of RCA jacks (subwoofer outputs) you would be best off getting a set for that too, but it’s not super important.

        The extra RCAs for a subwoofer output give you a bit more control but the Pioneer will be fine either way. If you have only one pair of RCA outputs on the head unit, the Pioneer can still work fine with it (you’ll change the input RCA switch) but won’t have a front/rear fader.

        It’s important to ONLY connect the RCA inputs or speaker level inputs – never both. The RCA connections have a better sound quality than speaker-level inputs. Connecting both will damage the head unit, and there’s no reason to do it anyway.

        I hope this helps, Dante, & have a great day!

  6. Hi Marty your work is very good and inspiring, you describe each and every detail of Gm 9705,
    One question in mind, as i am not so infornative about amps, at last lines you talk about limitations of voice quality of gm 9705 as compared to high end and high budget amps.
    So plz tell the model of some high budget 5-channel amps which should have more sound quality then this one.
    Thanks for your time and great work.
    Gull Ahmad

    • Hi Gull & thanks for your comments. :) You don’t specify if you mean other class D 5 channel amps or not, so I’ll have to assume you many any kind.

      Here are a few (bear in mind, for class D amps with even higher sound quality you’ll hve to pay more):
      – Alpine S-A55V, PDR-V75, PDX-V9, X-A90V
      – JL Audio RD-900, HD900/5, XD700/5v2
      – Kicker 46CXA6605
      – Rockford Fosgate R600X5

      There are some cheaper class A/B amps like Planet Audio but they’re average in terms of sound quality. Hifonics also makes a 5 channel amp that’s worth checking out. However, anything cheaper than the Pioneer models aren’t likely to have especially great sound quality.

      If you’re most concerned about the best sound quality possible + affordability you’ll need to buy a brand name class A/B amp. The tradeoff is that you won’t get the same power capability as a class D amp.

      Overall, though, the Pioneer is a better value & does quite well for most people.

  7. Hey! Thanks for the great article! It seems that the D9705 amps are the best 5 channels for the price and power you get until you start spending a lot more. I’m wanting to power 4 speakers and a sub, roughly 50 RMS (110 max) speakers and a 300-500 RMS sub. First question: What is your opinion on a 5 channel amp, vs a 4 channel and a monoblock? Aside from having to wire two amps, would the two perform better and cooler than one? I could buy new or used. It seems there are many more options for used 4 channels/monoblock than 5 channel amps, and therefore you could get better quality for less.

    Second questions: If your speakers run at 4 ohms, on the 5th channel, is it dependent on your subwoofer, whether the 5th channel runs at 2 or 4 ohms? From my research, it seems that each channel is independent, and therefore you could run the 5th channel at 2 or 4 ohms, even if your speakers are 4 ohms. That was a lot. Thanks for your time.

    • Hi there.

      1. The answer is, “it depends.” For example, not all 4 channel amps are class D. Class A/B amps are often the case for budget amps however they run warmer as they’re a lot less efficient. Also, while you do have more power options when using 2 separate amps, it comes at the cost of how much space 2 amps (vs a 5 channel amp) take up.

      5 channel amps are less common for sure, but have a lot to offer these days. Really it depends on your needs, budget, and what does or doesn’t work for you. I definitely recommend a good one like the Pioneer 5 channel as it’s a lot in a small package.

      2. The speaker impedance rating for each amp channel is the minimum it can handle. So you go by that for choosing speakers to connect to it. When main amp channels are bridged, however, usually the minimum is 4 ohms (vs the 2 ohms stereo rating for some amps).

      The 5th channel is often 2 ohms (and even 1 ohm, in some cases) as it’s intended to be used just for subwoofers, unlike the other channels. You can run it at anything equal to or above the minimum required rating.

      Have a good day. :)

  8. Hi, Marty. Thanks for the detailed review.

    Do you think it could be possible to replace a factory amp with this one without running all new RCAs throughout? Factory amp has a harness connected in with standard speaker cabling. Fwiw, the vehicle in question is a Mitsu Montero (F + R + sub).

    Thank you!

    • Hello Sergey. It usually can be done but it depends on the particulars of the factory system. For example, some factory amps simply have regular full-range amplifier outputs (easier to deal with) while other factory amps with separate tweeter & woofer outputs. Those will be more complicated (would need speaker crossovers).

      But in general, yes it can be done. The amp has speaker-level inputs and a subwoofer signal derived from the main channels so it should be a good fit for your situation. :)

  9. Marty, thanks so much for the quick reply. Currently the sub output is tied into the rear speaker output (it blew, and to turn it down I have to LPF the hell out of rear speakers as a whole via an aftermarket deck).

    • Yep, sounds like it’s time to install an amp. A head unit can usually only supply about 15W-18W or so per channel.

  10. Marty help!! I have 9605 and somehow i lost the speaker input adapter. I think my kid absconded with it and I cant find it. I found a generic one online but the wire colors dont match. Any chance you can tell me the pinout of the adapter so I can the generic one work?!?!?! (or if you wanna sell me your adapter lol). I was so ready to install my system and now am dead in the water!

    Thanks !!!

    • Hi there Erik. I’ve gone back over my photo and another photo I’ve found for the 10 pin speaker level input jack and I’ll put the pinout here. Unfortunately I no longer have my test amp or I would have been glad to sell mine to you (sorry).

      Here’s the pinout, as viewed facing the amp:
      [1] [2] [3] [4] [5]
      [6] [7] [8] [9] [10]

      1, 6 (gray, gray/blk): RF+, RF-
      2, 7 (wht, wht/blk): LF+, LF-
      3, 8 (Not used)
      4, 9 (vio, vio/blk): RR+, RR-
      5, 10 (grn, grn/blk): LR+, LR-

      Hopefully that helps!

  11. awesome!! thank you so much.. truly appreciate the response! I was wondering why there were 10 pins when only 8 were needed.. makes sense 2 are blanks!… seriously thanks again! My system is up and running!

    • Marty, thank you! Your guide helped me out tremendously with installing my GM-9705. I have one more question. I was tuning my amp, on channel b, as I was carefully turning the frequency knob, it wouldn’t stop turning. It turns continuously, clockwise & counterclockwise. I turned the knobs on both channel a & the SW channel the same way, I turned all the way to see what position I had to turn it back to. Unfortunately for channel b it didn’t end! Looking at your pictures with what’s on the inside of this amp, the knobs don’t look easy to get to, to fix, or am I wrong? What do you suggest?

      • Hi Rob, thanks for the comment.

        Hmm, that’s a shame to hear. Yeah it sounds like the potentiometer is broken internally, like the wiper inside is broken and no longer hits the stopper like it normally would.

        Well, it’s very similar to other car amps in terms of opening it up and getting access. Plus you’d need to be able to find the identical part to replace it with (it might be an Alps brand pot, but I’m not sure). You would also need desoldering tools, too.

        If you’ve disassembled a car amp or similar equipment & desoldered parts before then you probably can. If not, I don’t recommend it and you should give Pioneer a call and ask what your options are and go from there. Really it depends on your level of electronics work experience.

        I hope you can get it resolved without too much grief. Good luck!

  12. Hi Marty,

    Still using these amps? Any problem you have encountered specially the heat it generate? I have th 9705 and im bothered about the heat it generates even though im not pushing it hard. I even try idling it with the input rca disconnected and found it hotter than my other amps. I have a jbl cs60.4, pioneer GM A6704 and groundzero GZTA 5120X-II to compare it. Btw, thanks for the comprehensive review.


    • Hi Paul. They’re not currently installed as I had to remove them for testing other ones. However, no I never had a problem with heat. The amps were warm at most, never hot. Are you driving 2 ohm loads or only 4 ohm?

      When you let it idle without a signal, for how long did you do it? If you start the amp with it cold and no signal, give it some time, and it gets hot, then there’s likely an issue with the amp. Thanks for the comment about the review and for dropping by!

      • Hi Marty,
        I am interested in getting the Pioneer GM-D9705 for my 9th gen Honda Accord 2014. My car has a factory amplifier powering front components, rear speakers and a sub.
        How should I pair this amp to my current system?
        I’m new to car audio and I am unsure what I should do with the connection. Can the pioneer amp be wired after the factory amp?

        • Hi Darren. Generally speaking you when using an aftermarket amp with a factory “premium” system (factory amplified) you’ll need to disconnect the old amp and connect the new amp’s speaker outputs to the factory speaker wiring. If the factory amplifier has built-in crossovers and splits up sound between speakers (like multi-speaker factory systems often do) it’s going to be more complicated.

          As this is a more detailed project you should be able to find out more at the Honda or Honda Accord forums. You may need an integration unit or signal converter like from AudioControl depending on the factory head unit. This is one reason people often just replace the factory head unit with an aftermarket one and get rid of the headaches altogether (and get better sound, too).


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