I've been offered a racked Neve 33135 for £700 in cosmetically good condition but with a fault that causes the audio to "fade out" after about 1hr of use. Turn it off/on again and it fires up for another hour then dies again. Has anyone come across this problem and would you guess it would be an easy fix or maybe just walk away? I'll openly admit this is totally a slut thing... I'd love a bit of old Neve in my rack!!
You probably have a component in there which is thermally intermittant. Get a can of freeze mist at the electronics supply store, open the box. When the sound fades out, start spraying it on the logical culprits like transistors, coupling caps, and resistors in the signal path. When the signal comes back, you know you have the right component.
I have 2 33135's that had very intermittant behavior until Geoff Tanner informed me that those modules outputs must be terminated w/ an output tansformer.
Once I patched the output into the transformer (basically a big grey box that sits in the back of my rack), I had no problems whatsoever.
Without the transformers theres all kinds of weird/unexplicible behavior.