Looking for a good ready made mono amplifier board for my 8" ONKYO subwoofer

[playtime]

Hi Guys,
I can't live without my Home Theatre.
I am a newbie, having Onkyo HTR494 Receiver with an Active Subwoofer.(120-240V 20W, having 8" 4ohms 80Watt 27Hz-150Hz driver)
last week my Subwoofer Stopped working, due to shortage of semiconductors the service center is not able to fix that.
I tried buying a new one but, that is also not available.

I was thinking of assembling my own. There are lots of board available in the market but, I am very much confused with them.
Could anyone help me by answering my questions here.

1. Can I use stereo amp for my SUB as my receiver's bass out is already managed by AVR?? or strictly required a bass amp??
2. my Onkyo 658 Active Subwoofer is low powered, rating on the back plate is 120-240V 20W. can the same rating amp be made from the boards available in market??
Because after some research I found that my assembelled amp's input will be somewhere between 80-300 watt.
3. which board I should go for?? TPA3116, TPA3116D2, TDA7294,TDA7297,TDA7492,TDA7498.??
4. what type of power supply should I go for and most importantly with how much Amperes??
5. It has become complicated for me as my country showing either 50W, 100W, 500W, 1200W pcb with the above chips.
6. My 8" driver is rated as 80Watts and As per my assumptions I should go for the board which may deliver 120-150 watt output, can I use the 500watt?? but what happens if I am not home and somebody suddenly increase the volume to its peek??? I am afraid.
7. is my Sub's Amp just increasing the volume or enhancing the voice also as the sound is already coming from a rich AVR.??
8. At last, my Onkyo SUB Amp's plate has 2 big 50V 10,000uF capacitors and no boards in the market have even any capacitor close to it. all have max 480uF. I heard that good bass amp needs big capacitors to deliver the drum sound one after another.
I have attached my Sub Amp's Pic too.

All your answers shall be highly appreciated.
Thanks
Nitin

 

[Pogre]

Okay, I'm not educated enough to guide you with your fix, but have a question or 2 for ya. It's usually not as simple as just swapping out an amp tho. Often there's a level of dsp involved as well.

1. How much are you willing to spend to fix it?.
2. Have you looked into just replacing that sub?

You can find a new sub that will seriously outperform that little 8" for less than $150. For 4 or 500 dollars you can get something pretty decent.

This 12" model from Monoprice is a budget sub, but for $140 I'll bet it blows the doors off that little Onkyo.

Monoprice 12in 150-Watt Powered Subwoofer, Black - Monoprice.com

When you want your bass down low, you need a subwoofer as part of your home audio/theater system. Monoprice™ has the basses covered with this 12 inch, 150 watt (RMS) Powered Subwoofer

www.monoprice.com

 

[playtime]

Cant Afford to Replace whole Sub.
Just need to assemble.

 

[Pogre]

Cant Afford to Replace whole Sub.
Just need to assemble.

Okay, bummer. If I knew more about amps I'd try to offer some more advice, but all I can say is good luck. Maybe someone here will be able to help.

 

[Pogre]

Cant Afford to Replace whole Sub.

Well wait, that's why I asked how much you can spend to fix it. That's necessary to know. You're going to have to spend something, and quite possibly as much or more than you'd spend for a whole newer better subwoofer. The one I linked is only $140... replacing or rebuilding that amp might cost you that much...

 

[playtime]

Hi,
Thanks for your suggestions.

The service centre told me it would take 15$ to repair that. But, parts not available.
If it would be fully destroyed I would love to buy the new one.
But, confused whether to spend 150$ against 15$.
I can spend anywhere between 30-50$ as assembling cost.
.

 

[Pogre]

Hi,
Thanks for your suggestions.

The service centre told me it would take 15$ to repair that. But, parts not available.
If it would be fully destroyed I would love to buy the new one.

If it can be repaired for $15 and you're tight on budget then that's the way to go. However...

But, confused whether to spend 150$ against 15$.

If you can't source the parts then you might not have a choice. I will say that I've heard that subwoofer and was very impressed with it for the cost. It's a nice clean subwoofer.

I can spend anywhere between 30-50$ as assembling cost.

Hopefully someone can help you find alternative parts, but it's not looking good.

 

[TLS Guy]

Cant Afford to Replace whole Sub.
Just need to assemble.

Is the sub ported or sealed? If ported there will be no problem. If sealed you will need the original amp.

If it is ported, then put terminals on the back of the sub and by an 80 watt four ohm stable mono amp. Probably your best bet, is to purchase a plate amp like this.