TDA7294 + Power Transistors AMP (TDA7293 to come also)


i don't plan to sell it.. just for collection on my work space. because i'm glad to try something new. if there are relatives who want it, i will give it.
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OK!

This is very good! I have to thank you and everyone...
having a broken tda and another defunct (suspect) tda,
went for this: LM3886 +sc5200sa1943...
and its very nice sounding right now.
Getting better ...
followed the schematic by Mr Feuerbacher, and added 1k input r,
didnot use local C but the 4x4700uf from the PS just the NPelec 2uf
beetwen +and- at the bipolar-chip node
maybe later i´ll try some nf´s to snubber the xfrmer or th bridge.
ithink its kind of bright if something maybe alittle on the edge at both ends, but nice and certainly flatter than some.
have to make voltage reducer with res and zenners for the mic section and the eq. also for the mp3 reproducer need like 12V
first pic: amp left , right is eq and behind mic input line input..
2nd: amp
3rd: xover
4th: amp
5.: chip
6th: wheres my glasses??
 

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there´s actually two 3886, and one is made with 22k-1k-47uf string,
the other, in use, is just 22k-1k no fbcap!
Used that before and less is more?
or else...
i´ll test drive vers 2. jejeje
letyou know later after all this mess is up and running.
Sorry, those two pics from my job!
 
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hey mr Andrew...
shure would like totry that too!
and, what PS willyou be using with it?
I have two big chunks of iron
like 80+80 secundaries like 1kva
those really need a soft start.
the 3886 is ok still sounding loud and clear
using it alone, without pre and eq
eqed alittle from the lap´s wmp
full output sounds alittle ragged but must be the lap output rather than the amp
 

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this thing really gets better!, isit sort of stabilizing or something ?
this the so called burn in?
the first clone i made didnot improve much the first ten or more hours
don´t know now, have to listen to it.
But this one when augmented with the transistors, started sounding kind of bad and was having trouble with a bad speaker, after changing to another bigger and more power withstanding speaker, left it for two hours full volume from laptop, then came and lowered for half hour and again full for four hours it got better and more today.
would like to measure but dont have the equipment
 
Thanks for your comments! and sharing.
This clone sounded not to good until reinforced with the transistors
and- also rearranged cables, grounds included,-
at every time i came to listen, turned it off discharged caps
and moved this and that ,turn on and listen
loud and quiet, get away some more time... etc.
 
I was going to do this with my single sided LM3886 PCB and added 2 pairs
Is it even possible? seems like it is but i belive it may sound not as good :(

If it sounds good I will do it it will cost around 80€ just to make 2PCBs with mid qualty
components...
An externally hosted image should be here but it was not working when we last tested it.

how to take screenshots


ITS NOT FINISHED BOARD.
Few more things to do but, heall yeah its going to kick butt, at least i think :)