Hello, I've built a amp using the following schematic and i want to know if the optional Ci capacitor must be a "non polar" capacitor. And also i get a hum when no source is connected and it goes away when the source (preamp) is connected and switched, i dont use the Rin. I would also like to know if i can use a input DC blocking cap, if i can what value should i use.
Thankyou for all your answers.
Daniel
Thankyou for all your answers.
Daniel