Author Options:

Passive subwoofer and receiver with "subwoofer pre out" plug in harman kardon avr 142 Answered


I have Harman kardon avr 142 with subwoofer pre out plug in (suitable for active sub), and passive pioneer subwoofer with two cords.

Between them I have rg59 with rca head (sub cable).

Is there a way some how to convert the pioneer sub to an active sub with rca plug in?


If you have a passive subwoofer but your AV-Receiver only supports an active sub you have two choices:

a) replace the passive subwoofer with an active one

b) use a LFE amp between the RCA pre out and and the passive sub

Unless the passive sub you currently have is of a particularly good quality, you might find option a) is your better option, if going for option b) you'll want to make sure the amp you use is intended for low-frequency


1 year ago

What lfe amp would you recommend? that will suit the pioneer sdv111 sub woofer ?(I added pictures of the sub)

I prefer low cost LFE amp that can make the job done with this low cost subwoofer...


It's difficult to pick out a recommended amp as the cost and specification can vary. According to the Pioneer manual (http://www.pioneer-latin.com/downloads/operating%...) the DV111 used a 60w amp with 8Ω impedance for the sub channel, so you will want something that comes close to this power output. Also you only require a single channel audio output, but you'll find that a lot of the amps will offer 2-3 channels, if this is the case you'll only wire up one of them.

The thing is most of the plate amp I find, are above $100, way beyond what I need for this sub.

Cost will be a factor, which is why I think replacing the sub may be the best solution. However you will find small amps for around $10, but I've never used anything like that before so can't comment on how good they might be.

I think with $10 I can take a risk, where can I find them?

Thanks fo the links!

Where to I plug my rg59 sub cable with rca head in the TPA3116D2 board? I think i see only the black 12-24v socket but no rca one...

And can I wire the inner subwoofer two cable cords to any of the 3 channels I want? will it work with 60w?

You'll either need to find one with an RCA input, use a RCA to 3.55mm jack adapter/cable or modify the board to include an RCA socket.

As I've said before, replacing the sub will be your simplest option, it may even turn out to be the cheapest one, especially once you factor in the time spent fiddling around trying to make things work.

As my father always says to me, buy cheap buy twice!

Is this board fine?


it has two rca inputs, so if i plug the subwoofer cable with rca head to one of the board rca inputs, will it work?

Looks good to me, see no reason why it won't work. Probably worth a try :)

According to the specs of the amp you need a power supply that delivers Dual AC at 12v @ 60w (i.e. it has TWO positive (+) capable of 30w each and one negative/ground (-) ground terminals). I'm guessing it's using dual power to supply L and R channels independently. The use of AC is a little surprising as most domestic applicances and circuits would use DC, but I'm no electrical expert so can't comment too much on this.

That one doesn't output 12v, only 5v and 24v. You want one that dual outputs 12v.

As you are only using one channel of your amp maybe it only needs one of
the power inputs to be live, but I really don't know. Also you may be
able to use a single power output and just run it in parallel with the
two inputs on the amp, but again I don't know if that will work either.

With the cost of the amp, power supply, and the time spent fiddling around
(with no guarantees that you will be happy with the end result), opting
for a new (or second hand) active sub might be the best way forward
here, I would really consider it if I were you.

Is this right?


So if I understand right, this is the kind of PSU I need? (only with 12v)


Depends on the power output you need/expect but Amazon and ebay are awash with neat ready made amplifiers you could put inside the speaker enclosure and get what you want.