[DGolberg]


Ok, I've tried asking this question a few different ways on another forum with no responses what-so-ever, so figured I'd try a different forum.

 

Anyway, I've got an old Klipsch ProMedia 5.1 system that has been used and abused for about 10 years (it saw an average use of 12-hours a day, every day for about 10 years).  Long story short, the amp for the subwoofer is dead/dying and needs to be replaced.  I had it "repaired" once, but the repair only lasted about 2 months before it started acting up again (it works when it wants to, let's put it that way).

 

As a more permanent solution, I decided to pick up a Yamaha RX-475 AV receiver to run the satellites (based on some advice regarding the satellites only), but this still leaves the subwoofer inoperable (well, depending whether it feels like working or not, that is) until I replace the amp.  Since I'm a bit of an audio-tech newbie, but still appreciate good sound, I figured I'd ask around and see what people would suggest for replacements for the subwoofer amp.

 

The speakers (it's a dual side-throw subwoofer) and cabinet are in good condition, for having been used as a foot-rest for 10 years (I know... some of you are like 

), so I can't bring myself to just throw them away and get a whole new subwoofer; even if it is slightly cheaper, and I already know these sound good to my ears!  As such, I'm looking for recommendations from anyone with even moderate experience with pairing amps to speakers.  While I would prefer a plate amp, I also wouldn't mind some kind of external amp that I can run it with where I could rig up my own back-plate for it.  I only need the amp to run the subwoofer via an LFE input from my Yamaha receiver as the satellites are now run directly from the Yamaha receiver.

 

Anyway, any help anyone can provide would be much appreciated!  I don't want to throw away perfectly good speakers just because I don't have an amp that can power them!

 

If you need any info about the speakers, let me know what you need and I'll see if I can find it or (if applicable) get a picture of it.

 

 

Thanks in advance for any help!

DGolberg

 

Edit: I hope I put this in the right sub-forum... it was either here or under Receivers, Amps, and Processors or Subwoofers, Bass, and Transducers .

 

[steve nn]

Something you should consider is why did your amp go out and after having it supposedly fixed, why is it acting up again? I'm not saying it's not your amp, but it could be you have a issue with one of your drivers that is causing your amp to act up or go out thus rendering a new amp fruitless.

 

[DGolberg]


Thanks for the response Steve!

 

When I had the amp repaired the first time, the tech performing the fix discovered several capacitors and resistors that were weak and/or damaged.  One resistor in particular was all but destroyed by heat due to bad placement in amp design (an issue brought up by the tech as well as others online).  The sub also works fine on occasion (like mentioned... when it wants to).  When it does decide to work, it will usually work until I turn it off for a while, then it won't always come back on or may take a long time to come on and stay on.  It seems as though the amp needs to physically heat up before it will come on as it is more apt to work when the room temp is 80 degrees than when it's 72 (floor heat without a thermostat is a pain to control, but it's not my place...).  There is also no distortion at all in the audio when it is working... it sounds like the day I bought it!  If there was a driver issue; wouldn't that cause distortion?

 

Anyway, I'm sure enough it's the amp that I'm willing to take the risk on replacing it; I just don't want to cause additional damage due simply to my lack of knowledge causing me to pair the wrong amp to the speakers.

 

[nichol1997]

Did you check ebay for a OEM replacement amp? It seems this would be the easiest thing to do.

 

[DGolberg]


Since the original, custom manufacturer's amp, is prone to failure already (I got lucky with mine lasting nearly 10 years), and since I no longer need the additional outputs for the satellites, I'd like to replace it with a better built, subwoofer specific amp, but don't know what to look for as far as specs.  Also, the ProMedia Ultra 5.1 system was discontinued some time ago, so the only amps I can get for it (which are made specifically for it) are all used, and likely to fail right away again, anyway; in addition to already having their original design flaw(s).

 

[steve nn]

I've been thinking on it and just don't know what to tell you, to many unknowns. I know what I would do but that doesn't seem to be the route you want to take.. at this time anyway. Maybe another with more expertise can help you out?

 

[DGolberg]


Understandable.  Thanks for at least looking into it, Steve!

 

Just curious, what "unknowns" do you need answered?  I might be able to find the data for you.  As it is, I've taken the sub apart a couple of times myself, in the past, looking for bulging capacitors or burn marks (about the extent of my circuitry knowledge).  I work with computers a lot, so I know how to handle circuit boards and spot components on the board showing physical damage, but haven't really learned how to build my own boards, yet, or how to test the individual components for internal damage/degradation.

 

When I had the sub apart, I also did an Ohm test on the speakers and they appear to be 6 Ohms each (Ohm meter read about 5.7-5.9 testing them individually), and are connected in series; though they look like they can be easily changed to parallel if need be.

 

Anyway, if there's any info you need that's not available, I can see if I can find it.  Otherwise, I completely understand if you're not comfortable giving advice on this issue.  The lack of data might explain why I was having trouble getting assistance on the other forum as well... I've found it particularly hard to find the sensitivity of the speakers, for one.

 

[steve nn]

Well as you know you need a cheap plate that can handle a 3ohm load then and or a hp possibly way up high unless you power accordingly. That sounds custom to me. I haven't dug into it but can so you're on top of it. You very well might get away with a cheap plate at 3 but like you said you run constantly and heat affects it. Doesn't sound good to me. Good luck though.

 

[Bombelman]

How about a Plate Amp from Parts Express ? Yung, Bash, Dayton, Technics, etc...

4ohm load....