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Worth Replacing Amp?
- Thread starter Rottmannash
- Start date
Here are Canadian prices for subwoofers. The prices are about as much as the plate amp you have a estimate for.
OP
- Thread Starter
- #3
Thanks- that's what I suspected. Wish I could repair the amp but this model has a history of blowing amps.Here are Canadian prices for subwoofers. The prices are about as much as the plate amp you have a estimate for.
DVDdoug
Major Contributor
- Joined
- May 27, 2021
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It's possible that the original amp has some EQ built-in to flatten and extend response. Once the subwoofer has some electronics in it it's pretty cheap and easy to add a little custom optimized EQ. You won't know and you can't measure a dead amp... Some plate amps have adjustable EQ but you don't know exactly what old one is doing.
,,,A different plate amp will work OK but it may not be optimized for that particular speaker.
,,,A different plate amp will work OK but it may not be optimized for that particular speaker.
If you hook it up to an AVR, any old amp will do just fine. The AVR will do the processing for you.
restorer-john
Grand Contributor
Sadly, most powered subwoofers these days use really nasty and cheap Class D 'modules' which are unrepairable, or at least coated in some much hard-to-remove glue and unmarked components as to make it virtually impossible.
But, It's always worth having a dig around to see if it's something simple and easy. What are the symptoms?
But, It's always worth having a dig around to see if it's something simple and easy. What are the symptoms?
OP
- Thread Starter
- #7
It turns on, the power light goes green than almost immediately turns red. I got it for free from someone who didn't want it.
OP
- Thread Starter
- #8
Sounds like it may be worth using one of my class D monoblocks to power it from my AVR and let the AVR do the cut-off. I suppose I should screw the old plate amp back on? To seal the cabinet?
This is a question I am interested in but I have read kind of opposite answers.
Is it possible to change the original plate amp of a sub (that of course applies whatever eq the sub needs) for a different amp and just correct the response as needed measuring/EQing as you would probably do anyways for room correction? Or is it more complex than that and better not bother if you don't know the specifics of what the original amp/dsp was actually doing?
Is it possible to change the original plate amp of a sub (that of course applies whatever eq the sub needs) for a different amp and just correct the response as needed measuring/EQing as you would probably do anyways for room correction? Or is it more complex than that and better not bother if you don't know the specifics of what the original amp/dsp was actually doing?
OP
- Thread Starter
- #10
I was wondering the same thing.
I assume that it is a Sealed acoustic suspension design (from the look of it)...
I would wire the driver directly to the appropriate speaker inputs, and use an external power amp to drive it...
Something like a Crown XLS would do the job easily, and would also have onboard crossover... (lots of options in external amps, obviously!)
The only thing to watch for, is if it is indeed sealed, you need to ensure that you thoroughly re-seal it when putting it back together.
I would wire the driver directly to the appropriate speaker inputs, and use an external power amp to drive it...
Something like a Crown XLS would do the job easily, and would also have onboard crossover... (lots of options in external amps, obviously!)
The only thing to watch for, is if it is indeed sealed, you need to ensure that you thoroughly re-seal it when putting it back together.
Read for instance what this guy says. Wise advice or bullshit? No idea but would love to hear someone's expert opinion:
"One issue I can see with converting an active sub to passive is with the use of equalization some subs employ to extend the low frequency response of the assembly. This is done to provide the same acoustical output of a larger passive enclosure within a smaller one. The circuitry often provides for sub-harmonic filtering as well to reduce power consumption.
The result of removing the active eq may result in a reduction of low frequency expension, higher Q (ringing) and an overall narrower band of output."
Convert an active sub to passive?
I know some of us here on AK are stretching our budgets by bringing new life to old gear that wasn't getting proper respect. Subwoofers with dead plate amps seem to pop up from time to time for free or very little money, but $100 on a new plate amp often defeats the benefits of a free sub...
audiokarma.org
Have you tried it in all configurations? (High level, Line in and LFE)
OP
- Thread Starter
- #14
The amp shuts down even when unhooked from input after a couple seconds.
The plate amp is toast. It is going into protection when it fires up. Restorer John could fix it but it is not worth shipping it to him. You can get a brand new RTI 12 inch Polk sub for around $299. Plate amps for subs are known to fail all the time. If you stay on the inexpensive end of the spectrum, you can replace the entire sub whenever the plate amp fails. Usually AFTER the warranty is up! 
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Some of the amps on the
PSW 505 I’ve seen have BASH written on the back under the Warning labels in the center. Yours doesn’t but the one I see for sale for $249 does have BASH on it.
Wondering if one or the other has issues?Similar threads
