Distorted sound in Parasound A23 power amplifier


I have bought a used Parasound A23 power amplifier and the sound is distorted. I have connected different preamps with the same distorted sound. What is wrong? Is there a problem with the amp, the preamp or the source component? My standard setup (integrated amp and speakers) is working normal.


thanks for replay!


Really hard to guess on this one. My guess would be the amplifier, or you are overloading the input of the pre-amp. What is your source and what voltage output does it have?  

I have tried Mdac+ which got output voltage 4.5Vrms ±0.1 (balanced) and output impedance 20ohm (balanced). I know that this is a dac but it should also work as a preamp. I have also tried preamp output from CXA80 integrated amp (unbalansed), I didnt found the output voltage. Same distortion on both. Im not an expert on power amplifiers 😉 Im feeding the dac with upsampled dsd audio signals using a computer and hqplayer.

I dont have distorted sound using the CXA80 integrated amp and Mdac+ connected to a computer with USB-B. The voltage output of USB-B is 5V.

Input stage of the amp needs to be checked professionally. Could be caps or could be transistors.

The distorted sound sounds like the speakers are blown but they are working normal

Most likely you have a bias issue or blown output devices.  Local to New Jersey I can take a look at it.


Happy Listening.