Ultra Simple Class D

Hi at all!
This is my pcb of this amplifier from Stewin project
I've a problem the output will feel very little in the speaker.
I'm using +-38V DC from project89 of Elliot sound (step up converter from 12V to +-40V), in the tl074 I've 4,60V, I've tried to change the 2,2k resistors with 1k but nothing has changed.
The toroid it's a 106-2 it's red on all the faces.
The speakers have 2ohm
 

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stewin:
Yes..that r12...and tl074 has a very slow rise/fall time and that creates deadtime also.

abarth92:
tri this:
1.Inject signal directly into pin 2 at tl074.If this doesn't work try:
2.Disconnect speaker and conect 200 ohm load. Disconect R12 .Connect T1 and T2 comman base to to +40 volt and -40 volt with 4.7 kohm resistor.See if you have normal output swing(+vcc and -vcc).
 
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abarth92 the amp works the way it is without modifications please check your soldering and components . i even posted pictures of my amp at diysmps

>>>>>and i have noted you are using single sided pls ground properly because the top layer connects ground (0vlts) to the rest of the board<<<<<<<<<<<<< when i used single sided i had use jumpers to make sure all ground planes are connected.
 
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Hello people, okay? I just set up my prototype in a proto-board. As I said I used a complementary pair (irf640 and IRF9640), although I'm not using a source of + - 60, but one of + - 25.

I'm impressed great sound quality I got, and how friends asked you guys post here some parameters that you guys have questions. First notice that I use an oscilloscope for PC, what do not cease to be a great tool and it got the values ​​of the parameters.
Again, these are values ​​that got in my equipment, using sinusoidal signal generator with a frequency of 1khz:

Power Supply: + - 25VDC (50Vdc).
Power (rms): 112.5 @ 8ohms
Sensibility: 0.8 V
Freq range: 20 to 18khz.
input impedance: 47kohms.
output impedance: 4ohms.
THD @ 1kHz: 0.18%
THD + n @ 1khz: 30.4%



even more
 
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