ebay tda 7294 2.1 amplifier sugestions

[tigox]

Hey there, i found this amplifier on ebay, http://www.ebay.com/itm/2-1-TDA7294...mplifier_Parts_Components&hash=item1c2f8021af and for the price i think it's interesting, does anybody have some experience with this amplifier, or does somebody own it?
Thank you

 

[Einric]

I stay away from E-Bay chip amps that have integrated power supplies.
I've been burned a couple of times.

 

[tigox]

i'm sorry vut what does an integrated power supply do in this amplifier?

 

[DUG]

Integrated supply means that the bridge rectifier and filter capacitors are mounted on the same circuit board.

IF you were able to find a transformer that gave a peak AC voltage of 40V (recommended from datasheet) and had music that tried to draw full power from one rail on all channels (80W+80W+160W) at the same time you would find that the filter caps on that board would not be able to keep the voltage up high enough to deliver the power.

60W+60W+120W yes...80W+80W+160W not quite. (my calculations)

Buying them this way is easier but limits your options for stiffer supplies.

If you don't need the full power it will not be an issue.

 

[Einric]

Not to mention that the circuit layout can cause all sorts of noise.

I purchased a TDA7294 Bridged 2ch on E-Bay and there are posts on this forum with directions on how to fix the HELL that is in the circuit design.

A lot of it stemmed from poor power supply design and layout.

 

[tigox]

i am using an smps that has rectification , can I r remove the power supply of the amplifier board and use the one on the smps ?
and also could you post the link that shows how to fix the problems of some of these amplifiers?
thank you

 

[Einric]

HERE is one of the strings that describes the noise issues.

It ended up being a real shenanigan to get working right, so... Mine still sets under a table in my garage.

There are a few others here on the Forums.

 

[hansibull]

I'm pretty new in the "gainclone game" but recently I bought about the same board, but instead of 4x tda7294 it's 2x lm3886 for the midranges and tweeters, and 2x TDA7294 for the subwoofer. The sound quality is perfect, and the chips is definitly genuine. The only con is that there where some poor solidering that I have to fix myself. there where no short circuits, just cosmetic.
LINK:
YJ 2 1 LM3886 TDA7294 68W 68W 160W Amplifier Board Speaker Protection | eBay


I also found this board. It's a little bit more expensive, but have more expensive parts
Assembled TDA7294 2 1 Channel Power Amp Board with Speaker Protection Upgraded | eBay

 

[tigox]

Yeah great amps those two, my only problem is that they can only support 8ohm subwoofers .... if only they could support 4ohm ones...

 

[hansibull]

I'm using a 4 ohm sub, and it's no problem, exept more heat form the TDAs