How To Connect A Subwoofer To A Receiver Without A Subwoofer Output

So your receiver doesn’t have a subwoofer output. You’re probably wondering what the heck you can do about it, and you might be worried if you’ll have to spend a lot of money for either a new receiver, subwoofer, or both!

I’ve got great news – there are several simple ways to connect a subwoofer to a receiver without a subwoofer output.

Read on and I’ll show you several options along with easy and clear diagrams to help. There’s no need to throw away your old receiver or break the bank!

Home stereo subwoofers explained

Passive vs active home subwoofers diagram

Comparison of non-powered (passive) vs powered (active) home stereo subwoofer enclosures.

Home stereo subwoofers are available in two different types: powered (“active”) and non-powered (“passive”).

  • Powered subwoofers use a low-signal signal which is boosted greatly using the built-in speaker amplifier, power supply, and crossover. These types are one of the most common and in many cases use an RCA type input jack to connect to the receiver for sound.
  • Passive (non-powered) subwoofers are simply a subwoofer speaker inside the bass enclosure which is directly wired to the speaker terminals or a passive bass crossover inside. These types are less common.

How a subwoofer produces bass

The subwoofer works by resting inside of an enclosure designed for it and to produce deep bass when playing music limited to low-end bass sounds.

In order to produce clean-sounding bass without vocals or other sounds a subwoofer can’t properly produce, a low-pass crossover is used to allow only bass frequencies to pass & be produced. The problem comes when you try to connect a subwoofer to a signal without a crossover – it sounds terrible!

The subwoofer output jack on a receiver is normally limited to passing bass only, either from stereo music production or from the “.1” subwoofer channel (dedicated subwoofer music content) of a surround sound system.

For example, when you hear references to “5.1” or “2.1” speaker systems or surround sound audio for movies, the first number represents the number of main speakers. The “.1” is used to represent a sound channel limited to only bass for optional subwoofer use.

Powered subwoofer inputs & controls you may (or may not) have

Powered subwoofer example with inputs and controls labeled

Example of a powered subwoofer with 2 types of signal inputs (speaker level and RCA jacks) along with sound controls. Note: Not all subwoofers have speaker level inputs, which makes it a problem connecting them to a receiver without a subwoofer output.

Powered subwoofers usually have several inputs and controls, but it always depends on the brand and model. Here’s an example of what you’ll usually find:

  • Power input (AC outlet power)
  • On/off switch
  • RCA input jack or a pair of jacks
  • Subwoofer crossover adjustment
  • Subwoofer level adjustment know (the amplifier’s boost level)

The subwoofer input jack usually connects to a single mono (monaural, meaning both stereo channels are combined into one) output jack on the receiver.

Receiver subwoofer output jack example

Example of the mono RCA subwoofer output jack found on many home receivers. These connect with a single male to male RCA cable to a powered subwoofer.

Some models also include speaker level inputs, meaning they can be used with any modern or old home stereo receiver without a subwoofer output.

While that’s nice, if yours doesn’t have that feature, ordinarily you’d need to buy a different subwoofer and waste money.

In fact, some of the information you’ll find right now on the internet says that you have to buy another subwoofer if you don’t have a receiver with an output jack. That’s simply not true.

As I mentioned at the beginning of my article there are several ways to work around this problem.

Diagram & examples: Connecting a subwoofer to a receiver without a subwoofer output

Diagram showing how to connect a subwoofer to receiver with no subwoofer output

1. Connecting a receiver to a subwoofer with RCA input jacks

Example of a powered subwoofer RCA jacks & RCA Y adapter cable

Left: Example of a powered subwoofer with 2, instead of the typical 1, RCA input jacks. Right: An RCA Y adapter that can be used with a line level converter to connect to a subwoofer with a single RCA input jack.

For subwoofers with only 1 or more RCA input jacks (no speaker level inputs), a simple way to connect them to a receiver with no subwoofer output is by using a line level converter.

What is a line level converter, and how do they help?

Line level converters are small devices that accept speaker wire connections and scale down the speaker level signal to a low level signal (RCA jack) type output that the subwoofer can accept. They’re extremely handy in the car stereo world because they make it possible to connect a stereo without RCA outputs to any amplifier.

They’re not commonly used for home stereos but still really useful there, too.

Image showing examples of line level RCA converters

Examples of 2 line level converters – both a 2 channel and 4 channel of each. 

How much do line level converters cost?

Line level converters range in price (for a good one) of about $15-$25 each. They’re connected to the speaker leads of a radio, receiver, or amplifier. RCA cables are then connected to the jacks provided. The internal electronics not only scale down the speaker output voltage from a receiver but also help prevent noise from the audio path, too.

If you’re using a subwoofer with a single RCA subwoofer input jack, you may want to pick up a “Y” RCA adapter to combine both receiver channels on the output side into one.

Subwoofers with 2 (stereo) RCA jack inputs, however, will need a standard male-male RCA cable.

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3. Subwoofers with speaker level inputs

Example of subwoofer speaker level inputs

If you own a subwoofer with speaker level inputs you’re in luck! You can connect these directly to your receiver’s speaker outputs, either by themselves (on unused speaker terminals) or at the same time with speakers connected to the receiver.

These subwoofers with this feature contain internal electronics that scale down the speaker signal from the receiver before it reaches the internal amp that powers the sub.

Additionally, there’s a low-pass crossover built in as well to produce great-sounding bass and no unpleasant parts of the music – just pure, low-end bass.

Connect these directly to the receiver just like you would another pair of speakers. 

Note: Subwoofers with speaker level inputs and outputs provide a way to easily connect both at the same time. The outputs are internally connected to the input connectors, making it easier to add speakers and the subwoofer to a receiver simultaneously.

3. Connecting a receiver to a passive (non-powered) subwoofer

Example of a passive subwoofer low pass crossover

Example of a passive subwoofer low-pass crossover. Passive crossovers, unlike electronic crossovers, work using capacitors and inductor coils instead of electronic components.

If you’re wanting to use a non-powered (passive) type of subwoofer, there’s still hope, although it can be a bit harder to find the right parts and set up vs using a powered subwoofer.

To use a non-powered subwoofer, as shown in my diagram above, you’ll use a low-pass subwoofer speaker crossover which is connected between the receiver and the subwoofer enclosure. These filter out higher frequency sounds before they reach the sub to help provide clear & nice-sounding bass only.

How to choose subwoofer crossovers and where to find them

Speaker crossovers such as this are sold both in a single (one speaker) or dual (2-speaker) model, depending on the brand & supplier. They also have to be matched correctly to the impedance (Ohms rating) of the sub.

For example, subwoofer crossovers designed for 8 ohm speakers must be used only with those. Otherwise, the sound filtering is radically different and won’t sound as expected since the speaker load will react differently with the design.

Normally you’d choose one with a low-pass frequency of close to 100Hz or in that range. Speaker crossovers are sold where speaker parts & related components are sold as well as marketplaces like Amazon or Parts Express.

Stereo vs surround sound receiver subwoofer output differences

Stereo vs surround sound receiver differences diagram

Unlike older or standard stereo receivers, surround sound receivers have a unique output that comes from the surround sound movie or music source. However, in regular stereo listening mode, they act the same as regular receivers.

One thing to bear in mind is that when connecting a subwoofer to a receiver without a subwoofer output, you can’t get a separate “.1” bass channel as you can with surround sound receivers.

On the other hand, it may not even be an issue. In fact, the surround sound receiver “LFE” (low-frequency) output is considered optional – hence the “.1” name. There is a drawback, though: for some movies, especially action or other types, the bass channel can be very enjoyable.

Using a receiver without that output means you can’t get the same effect, but that’s only for surround sound mode. The good news is that in stereo mode, both new and old receivers have very similar subwoofer behavior when connected as you’ve seen here.

Just something to be aware of if you’ve ever considered upgrading later.

More helpful speaker info & diagrams

I’ve got lots more information to help you get your sound system going:

Got questions or comments?

Feel free to leave a question or comment below if I can offer help. (Please be specific with information when referring to speakers, receivers, amplifiers, or other parts so I can help you the best I can)

You can also reach me directly at my Contact page. Thanks!

Your comments are welcome!

  1. Sir,
    I have not come across such a detailed and helpful article with explicitly clear Diagrams, on ‘How To Connect A Subwoofer To A Receiver Without A Subwoofer Output’, anywhere on the Net. Hope it will help me to implement it in my System.
    Many many thanks.
    Rama Rao,
    Mumbai, India.

    Reply
      • I want to add a third active sub to my 2 channel stereo. My current two subs are wired through my amps speaker outputs. Can I simply add another set of speaker cables to my amp to signal the additional sub?

        Reply
        • Hi Kevin. That should work fine if they’re powered subwoofers. Generally, the electronics in the input sections of the subwoofer amp have a very impedance which means connecting them alongside speakers on the amp will still keep the load it sees really close to 8 ohms.

          In case you have any problems you could also use a line level converter then go out via the RCA jacks with splitters to run the signal to all of the subwoofers. Hope this helps!

          Reply
  2. Marty, First of all thank you much for such helpful information.
    I have been scratching my head back and forth and cannot find a way to connect my subwoofer to my Sony AV Multi Sound receiver Model: STR-DH590. My Subwoofer only has two connections. Speaker wire connections one Red (+) and one Black (-). However my AV receiver has 2 connections for a Subwoofer which are 2 RCA connections one for in and one for out. Please tell me how I can connect my subwoofer do I need a seperate amp for my Subwoofer?

    Reply
    • Hi Jesse and thanks for your appreciation of my article. :)

      If your subwoofer is not “powered” (does not have an internal amp already), then yes you’ll have to get an amp to power it. Your Sony receiver actually has 2 subwoofer outputs, not one in, one out.

      What you can do is consider using a small affordable mini amp like this to power your subwoofer and connect to the RCA outputs of your receiver: Lepai mini amp with built-in crossover

      Alternatively, you can also add your own subwoofer “plate” amplifier just like the ones built into home stereo subs, although that’s more hassle and they cost more. Hopefully this helps!

      Reply
  3. planningtopurchase a vintage amp… well no so vintage but they dont have sub out.. will make a gamble and hope this works.. btw.. have a sub wub with high power input so i guess i can connect this to speaker b while using a for my front speakers

    Reply
    • Hi Francis, yes if the powered sub has speaker level inputs you should be able to connect it like that with no issues, either on the B terminals or also at the same time as speakers connected to A terminals (as shown in the article). It shouldn’t matter.

      Reply
  4. Sir,
    Excellent article. I was not able to understand it enough to determine how to connect a powered Sub Woofer to a preamp / poweramp stereo set-up.

    Specifically, my preamp is the Schitt Freya+ that has 2 sets of single end out (RCA) that is 2 pairs. One pair is connected to the Power Amp which is turn connects to 2 speakers. My thought is to connect the Second pair to the power subwoofer low level input left and right. Does this make sense? Please advise and thanks so much

    Reply
    • Hi Michael. Yes, connecting the powered subwoofer to the unused pair of RCA jacks should work as you described. Ordinarily the subwoofer should also have a built-in low pass crossover which you’ll need as the RCA jacks will be full range outputs.

      Reply
    • Hi Michael
      Does your powered subwoofer work? My Dac/Pre amp is Topping D90 MQA. One is XLR output connected to the Power Amp which in turn connects to 2 speakers. The other single ended is connected to the powered subwoofer. But it didn’t sound good. Bass is too lean. I tried various methods to connect to the subwoofer:
      1. RCA cables to the powered sub low level input left and right. Bass is lean and there is a hum.
      2. Use a 2 RCA female Y Adapter Plug to a male then to the powered sub low level input left ONLY. Bass is lean still but hum is slightly less.
      It didn’t work for me. Thanks mate.

      Reply
  5. good day Mr Marty
    Sir
    i have Marantz NR1403 A/V receiver with Harman Kardon HKTS9 Subwoofer i cannot set up the subwoofer there is no sound coming.but the 5 speakers already have sound. thanks

    Reply
    • Hello, Victor. You should be able to connect subwoofer to the Marantz via the SW RCA jack on the receiver. If you’re not getting sound, I would be sure that 1) the subwoofer output on the Marantz isn’t disabled (not sure if that’s an option on the receiver), and 2) check the power on mode on the Harman Kardon.

      I see that it has both a trigger control and standard “on” option.

      Reply
  6. Hello and thanks for this. Can I ask you as in example 1 if the sub WASNT powered but had a single out cable usually simply hooked to its normal amp as part of a system via a single port and sub slot. Could you hook it up to a different/new amp as in example one even though its passive. THANKS

    Reply
    • Hi Jake. If I understand your question correctly, you’re asking about using a passive subwoofer that was originally for a different system with another amp or receiver.

      For a passive subwoofer, what you’ll need to do if you don’t have a dedicated powered subwoofer output available is to either (1) use a free speaker output + a low-pass crossover or 920 a mini amp with a built-in low pass feature. Of the two options, #2 is easier. You can find a mini amp like that for $20-$25 with decent power (you’ll need to spend for if you want a lot more power).

      Have a look at this article (example #3 specifically) for a better understanding of what I mean (just that you’ll have an 8 ohm woofer instead of the 4 ohm discussed): https://www.soundcertified.com/how-to-hook-up-car-subwoofer-home-stereo/

      If you don’t have a dedicated RCA output for the sub or you’ll need to use a line-level adapter to use the 2nd amp.

      Reply
  7. I have a vintage Mitsubishi DAM 10 and DAP 10 ( amp-preamp) — can I plug a subwoofer into this unit and if so how
    and what watt subwoofer would be best for this unit

    Please send response to my email as well

    much appreciated —

    Reply
    • Hi Mark. Sure, I’ll copy my reply here & email it to you.

      Basically, you should be able to simply connect via RCA cables to a powered subwoofer. Unless I’m mistaken it appears as if the DA-M10 has a pair of RCA passthrough jacks that you could use to connect to a subwoofer’s RCA inputs.

      Alternatively (or if that’s not possible) you should be able to use some RCA Y adapter cables between the preamp and the amplifier’s inputs if needed to get a 2nd pair of RCA jacks and go into the subwoofer RCA inputs. As far as a subwoofer goes, whatever fits your sound needs & budget should be fine.

      One like this Monoprice 8″ model would work well or you can browse what’s available at Parts Express too as they have a good selection.

      Reply
  8. Appreciate all the information. I’m going to try and use the line level converter to connect my sub to my stereo receiver. Is the wiring on the converter intuitive for stereo receiver applications, or will I have a tough time figuring out which wires to put where?

    My receiver is a Sherwood – Rx-4019.

    Reply
    • Good morning. No, it won’t be a problem. Those with colored wiring are labeled and/or include the wiring instructions. The ones that use wiring terminals to connect are clearly labeled as well. So it should be pretty simple.

      Reply
  9. hey i just have one issue. the line level converter you recommended requires a constant 12v + input, not sure how to make that happen with my av reciever setup. thanks for the help.

    Reply
    • Hi there. I’ll need to add a note about that so thanks for bringing it up.

      You could use a standard AC/DC 12V wall adapter with a +12V DC output, about 0.5 to 1A. Most have a barrel (round) connector which means you’d need to cut the wire unless you have one with a terminal strip connector.

      Reply
  10. Hi. Very detailed explanation but not sure I’m totally clear on my option. I have an old Denon 5.1 system & trying to upgrade using a Sony DN1080. My passive subwoofer has the 2 speaker wire connection. The amp has the Subwoofer OUT which I think is an RCA connection.
    Can I;
    1) get an RCA adaptor & simply connect the + & – wires into correct side (+/-) & then the one RCA into Amp.
    2) get an RCA adaptor for each wire & just connect one RCA into Amp (leaving other not connected)?

    Tks
    Tony

    Reply
    • Hi Tony. The RCA jack can’t power a speaker – it’s a low-level signal so you’ll need to amplify it for use with a non-powered subwoofer. While you can connect a non-powered subwoofer to unused speaker outputs through a low-pass crossover, using the SUB out RCA(s) is usually better sounding.

      Also, it sounds like you won’t have any free speaker connections anyhow.

      To solve this situation, you can:
      1. Use a small amp to drive the subwoofer
      2. Replace the passive subwoofer with a powered one

      Parts Express sells an affordable mini amp you can use to drive the subwoofer and connect to the subwoofer RCA output of your receiver. It’ll have a low-pass filter built-in also so the bass should sound right.

      Thanks!

      Reply
  11. Hi Marty,
    Thank you for those very detailed and instructive info and keeping up with everyone questions! Great explanation about speakers/Receiver connection!
    Just one other situation, that is probably obvious but wanted to get your feedback: I have a receiver Onkyo HT-R290 and a powered subwoofer. On the receiver, there is a specific line output for a passive subwoofer. Can I connect my powered subwoofer, using a RCA Y adapter cables, to the receiver, wit hour any risk of damaging it? Any particular setting on the powered subwoofer?
    Thx for our help!
    Didier

    Reply
    • Good morning, Didier, & thanks for the feedback.

      Unfortunately, no, you cannot connect a speaker level output like on yours to RCA inputs on an active subwoofer.

      If your powered subwoofer does not have speaker (“high level”) signal inputs, you’ll have to use a line-level converter to scale down the speaker level output from the subwoofer speaker terminal. Speaker outputs use a much higher signal than RCA inputs can work with. (See example #1 in the diagram)

      Reply
  12. I connected a powered subwoofer to the to a line out of my receiver to the low level in of my subwoofer and it sounded good but when I played music at a low volume..the sub was too loud and at high volume …the sub was too low…so I connected in line with the speakers through the high level input and output of the subwoofer and the subwoofer volume stays consistent with the volume of the music…which is good…….is that the way it’s supposed to work?……I don’t see why anyone would use the low level input….also…does the high level input/output filter out the low frequencies to my speakers possibly making them more efficient/brighter?…..does the LFE output of the receiver change amplitude when the volume is changed?

    Reply
    • Hello there, Jeffrey. What you describe isn’t typical at all. The subwoofer’s volume should change with the receiver’s volume, but it does matter which line out (RCA) jack you use. As I recall, there are some that maintain a fixed output level which sounds like what happened to you.

      A line-level output is normally used to provide a signal before it’s amplified – using speaker level inputs is usually fine if you don’t have an alternative, but isn’t the best possible in terms of signal quality. Line level is preferred if available.

      For example, with my home theater receiver, the LFE jack provides an output that’s proportional changes with the main volume. Normally you should only have to set the subwoofer’s gain and you’re done.

      Unfortunately with some receivers you just don’t have much to work with so using the speaker level outputs to connect a subwoofer may be your only real option.

      Reply

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