Point 2 Point (no PCB) for TDA7293, TDA7294, TDA7295, TDA7296.

Sparks? That's construction error. The connections are a bit flimsy and voids are causing sparks, so you need MUCH THICKER traces (probably needs reinforced with wire and solid soldering).

Also, the pi filter resistors need to be paralleled with minimum pin length and not look like a fishing net.

I think I see a ground loop that might cause dulling, so that needs fixed. Hey, I've made a drawing for you.

The green traces have the conductor Thickest to Farthest caps.
Or simply use the same length of cable to each cap from the star. It pays to match.
 
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Mr Daniel...:cool:
 

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i´ll wait to check this as is, and then add snubbers and
or smaller-bypassing-larger caps.
the one 220uf 63 that i had is for the fb-string,
should i bypass it with diodes?
and how doyou see the heatsink? what be better,
put the tabs directly onthe large Al piece?
or use the small plate first?
I´ll be using a fan fullspeed alltime, blowing into
the case and out at the other end.
Using both pieces to make U channel
 
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the one 220uf 63 that i had is for the fb-string, should i bypass it with diodes?
That value NFB-Shunt-Cap is small enough that it doesn't need diode bypass; however, 220u is big enough that you might want a little bypass cap for treble helper.
and how doyou see the heatsink? what be better, put the tabs directly onthe large Al piece? or use the small plate first? I´ll be using a fan fullspeed alltime, blowing into the case and out at the other end.
Well, I like it done normally. Watch out--those tabs have voltage!
Shoulder washers on tabs, tabs to insulating layer, insulating layer to big aluminum stuff, make the amp run cool stable and efficient so you can throw the fan away.
Enclosure with air intake vent and air output vent, and without needing a fan the warm heatsink will cause hot air to exit at/near enclosure top if when cool air is allowed to enter at near enclosure bottom. . . so you put the heatsink into this nonstop voluntary fanless draft of air to cool it.