Hybrid

[mensur]

Hi guys,
I made a hybrid amp. Roccaforte preamp and 100W MOSFET (TDA7294) SS amp.
I designed PCB (for the rocca and TDA):
Roccaforte Schematic & PCB.pdf
Some pics:







But I have a problem, I have noise and hum in the amp, here is sample:
Rocca Problem.mp3
and here is layout how i connected the amp,internally:
Rocca Layout.pdf

What can be the problem? Help me to solve this.

[varvaroid]

http://www.fileden.com/files/2008/12/25/2237836/Roccaforte/Roccaforte%20Schematic%20%26%20PCB.pdf
file not found :-?

[Дмитрий Ткаченко]

блин звук г... залей нормальный семпл.. у меня тож тот файл не открывается

[varvaroid]

Все что я услышал, дикий возбуд, дикий фон и хороший звук преда

[varvaroid]

блин звук г... залей нормальный семпл.. у меня тож тот файл не открывается

он тебя врятли понял
а семпл нормальный, показывает все что нада

[Дмитрий Ткаченко]

как то тиховато и шумно.... атак сам по себе семпл норм))

[mensur]

http://www.fileden.com/files/2008/12/25/2237836/Roccaforte/Roccaforte%20Schematic%20%26%20PCB.pdf
file not found :-?

Roccaforte Project.pdf

[EaNot]

mensur, filter cap must be after R15 (as 47u after R8)

[Jimmy_Page]

Hi. Please decrease size of your pictures. Preview of the pictures will be better.

[Ден2]

As i can see on PCB, the heater's feed is AC, whithout  "middle point" This may cause that noise.

[mensur]

Hi guys, I solved the problem, so here are the samples (recorded with cheap PC mic):
Ultra Sample1.mp3 - dry
Ultra Sample.mp3 - wet

[Troll]

So, where was that problem?  :-?

[mensur]

The problem was AC hum from the heather supply, I just DC-ed it(6.3VDC,old Hi-Fi trick), and it works great.

Here are the pics of the amp: