I decided to listen to good music after getting tired of boomboxes so I pulled my old 304 out of the closet and hooked it up to a pair of Polk Audio spks. The sound was refreshing. But I am hearing scratchy noises from the tweeter. I traced the problem to the 304 amp. Can anybody tell me what I can do (change caps, resistors, etc?) to be rid of that annoying noise? The noise is only present (on both channels) when there is music. During silence (in between tracks) its not there. I hope someone can help as I really do not want to switch to my Marantz PM57.
You might try this inexpensive experiment. Goto radioshack and get a electronic cleaner (spray). Unplug the NAD and open up the NAD, not touching anything inside - you can get a shock even with the power chord off !!!
Behind the knobs like balance, volume, bass, treble, etc, you will see an opening where you can spray the cleaner. Spray a little and move the knob in both directions, and repeat the process a few times. Wipe away any access on other parts.
Let it dry for a few hours, and plug it in.
I saved many old gears this way - hopefully it will work.
Thanks for the tip James - will try it out this weekend. Jan, I don't wish to spend on its servicing as the cost would not justify its worth. I'm pretty sure I can get it fixed myself if I can get the schematics. Anyone knows where I can get them?