Hum thru an HP100 Hovland


I have just bought a used Hovland HP100 preamp, it mated great with my CJ amps and Avalon spkrs, but... there are a couple of issues where I requiere your expert help:

1.- Everytime I get my hand close to the volume knob or whenthe CDP is reading the directory table index, it creates an audible hum in both spkrs, is that what microphonics is all about?

2.- There looks to be some dirt in the volume knob, since for each step I move it (up or down) a scratch noise is heard, what should I use to clean it since it has some silver and other exotic components involved in its design?

Thanks for your help, I really need it...

Go to Radio Shack and tell them the same and they will sell you a Electronic spray that is safe and effective for what sounds to be a little dust inside,which is a very common Problem.Hopefully this will cure you noise.If not your only out a couple bucks...Good luck!
The static can be solved by rapdily rotating the knob back-n-forth. Ss far as the hum? You may be the Hulk!
That volume control is very delicate and you need to pose these questions to the people who made the component -- call Hovland and ask them what to do (I believe Alex Crespi is still with Hovland -- ask for him).

The HP-100 preamp has unshielded outputs, which can be a big source of noise (you absolutely must use well-shielded interconnects on the outputs). In fact, well-shielded interconnects all around are a good idea with the Hovland.

Good luck.

I got rid of the hum problem placing an earth-splitter jack in the CDP. As for the cracking noise in the level knob I did call Hovland and gave me some options of sprays that could works, since there are some others that may be harmfull for the silver wireing in the knob.

Thanks all.