This power supply was intended for the NE5534 power amplifier project:

https://www.pcbway.com/project/shareproject/NE5534_5W_Utility_Power_Amplifier_c029aeb8.html

but, it can be used to power any low voltage power amplifier of your choice (up to 3A max current draw). It features 2 high current output connects, plus a smaller connector to go to a preamplifier which MUST have its own voltage regulation on it, as this PSU does not (example +/-15V). It also includes a muting relay to give anti-thump (turn on/turn off transients) when the amplifiers are powered up, or turned off.

If you find the relay doesn't pull in using the minimum 18-0-18 volt transformer, lower the value of R2 (say 120 ohm) or increase the value of C3 from 47uF to 220uF until the voltage across D6 is close to, or around 8 - 9V (which is the minimum pull-in voltage of the chosen relay).

Video of building the PCB: