Favorite H H Scott Tube Integrated Amplifier

Karavite, thanks for your thoughtful comments. Hopefully, you won't need service anytime soon, because Scott designed these units for very long tube life. My understanding is that their policy is to bias tubes at about 75% of recommended voltage. They must have done something right, because so many of these units built at least 40 years ago are still in circulation, still in demand and still making music. Some units even have their original tubes.

I second Linnlp12's prudent thinking about not changing resistors (or other parts) unnecessarily. It has been my experience that with components designed around older parts, whether guitar amps or stereo equipment, mixing in new components for modification or repair sometimes takes away from what you liked about the unit. If you have leaky caps or other problems, you do what you have to, but otherwise I think it is best leave things alone as long as possible. A Scott engineer was quoted as saying "if it measures well but sounds bad, it is bad. If it measures badly but sounds good, then you have measured the wrong thing." I think that like the people at Linn, they listened carefully, and that is what makes their stuff sound so good.

Someone told me one time, if it ain't broke, don't fix it. I try to follow that with the exception of coupling caps. I think changing the coupling caps can many times improve the sound of the amplifiers to a significant level. But changing the resistors, as I stated, previously destroyed the sound magic. As far as maintenance, the only things I would change are, first, some of the old units used selenium rectrifier bridges. Those were terrible and would fail according to my techie friend. That to me is the only required change I would make. Second, in agreement with the above posts about some of the older electrolytic caps. Finally, I would use a contact cleaner for the potentiometers and clean the grunge off the old RCA inputs. I didnt change them, because as a collector, I wanted them original. But for ease of use, if there was something I would not sell, I would change them. I have nothing left on Scott now but try and get a hold of that old absolute sound series. It was detailed and in some cases, Steve talked, I think, about maintenence. There was also an old Sound Practices or Glass Audio article about how to maintain these old pieces. I dont have these any more so I am sorry I cannot provide much detail.
Good luck.

Linnlp12, you already provided some excellent advice.

Thanks to all of you! You guys are the best!

I found the resistor replacement made a bigger difference than capacitor replacement in all my vintage gears. If I can find one, I would only replace with similar carbon resitors.