Usualy repairable. If you are competent, Unplug and pull off the lid and using a multi-meter check across the pins of the large power transistors (with the heat sink attached). if any of these are shorted out (on one component), the power transistor has blown. I have replaced Power Transistors in NAD, Marshal, Harmon, Cambridge Audio etc and most of the time, no other components need to be replaced. It is better to replace all power transistors on one channel . Some amps have fuse-resistors. these are often green or blue and are designed to go open circuit if overdriven and clamp the power amp to ground or kill the input to protect the power components. These are very cheep components and worth checking for. Beyond this, (assuming you have checked the basics like internal fuses and loose connections, dodgy switches etc. ) time to take to an engineer. CA's are nice amps so might be worth it.
Wid, June 2008
