Quote from: Bajaguy on July 28, 2014, 11:40:20 AM
One thing to keep in mind when you are matching a preamp to a chip amp is matching the input impedance of the chip and the output impedance of the preamp. Not paying attention to this will cause some nasty oscillations...... ask me how I know. :grr
Ok, how do you know this? Were you exceeding the input common mode range of the chip? Looking at the ST data sheet for the TDA2030A, the input common mode range is not specified. Ill bet strange things happen when you slam the input rail to rail or try to operate with a non-inverting gain of one.