I built an amplifier using several TDA7293 chips connected in parallel to make good use of my extra stock. The result honestly surprised even me!
I added a buffer stage at the input using opamps like the OPA1641, OPA1655, or OPA627, because I'm using an ALPS RK27 potentiometer for volume control directly at the output of a NOS DAC.
If you prefer, you can easily disable the buffer. Simply remove the opamp and short pins 2 and 3 of the socket.
In this case, R2 should be 47K, and you should remove both C23 and R1.
If you would like to keep an RC-filtered input instead, use R1 = 100Ω and C23 = 100pF.
Now, I’m excited to share some measurements with you!
EPIC W
1W Measurement (2x42VDC)
Output Noise (input shorted)
Schematic
Positive Regulator
Negative Regulator
I added a buffer stage at the input using opamps like the OPA1641, OPA1655, or OPA627, because I'm using an ALPS RK27 potentiometer for volume control directly at the output of a NOS DAC.
If you prefer, you can easily disable the buffer. Simply remove the opamp and short pins 2 and 3 of the socket.
In this case, R2 should be 47K, and you should remove both C23 and R1.
If you would like to keep an RC-filtered input instead, use R1 = 100Ω and C23 = 100pF.
Now, I’m excited to share some measurements with you!
EPIC W
1W Measurement (2x42VDC)
Output Noise (input shorted)
Schematic
Positive Regulator
Negative Regulator