I am trying to catch up on Jeff's Place blog. I really enjoy his excellent blog!
I am glad to hear he compares the mods he does with an original.
When I started I kept the best sounding amp I had original, always having a reference for a stock amp for mods to not come up with the false idea that everything I did was an improvement.
As Jeff was saying sometimes it's frustratingly not.
My original stock Fisher is now no longer stock. It was the amp that caught fire and melted an output transformer. My modded vintage amp in main system has long ago passed the stock vintage amp.
The Fisher was cathode biased. My tech guy who builds tube amps and repairs amps from all over Canada and the U.S.. A lot of expensive gear. Just love visiting him to see what is in for repair!
He changed the cathode biased amp to fixed bias. He did not like the circuit. He thought unstable. No argument here! (Chew up tubes catch fire the only thing it did well was sound great and very quiet)
A repair mans point of view will be different than ours.
I can not comment fully the change in sound but for sure sounds different. Technically the amp already running much cooler and seems much more stable!
So far the amp sounds stable and cooler, like it is running. The 4 Solen caps I suspect not helping either. Artificial sound. (Grainy that I am not used too)
It is my new project amp to see if I can push it passed my best modded amp.
My gut feeling is the phono stage is going to be much quieter. The one area I have not been super thrilled with. Phono stage was too noisy on other vintage amp. (Jupiter caps helped immensely there)
I have no idea of the differences in fixed vs. Cathode biased for sound?
I do have to say I am wayyyy more confident that the amp is stable!
My modding ability is extremely limited to part for part replacement, and a set of ears.
Now back to following Jeff's blog and his excellent crew!
I am glad to hear he compares the mods he does with an original.
When I started I kept the best sounding amp I had original, always having a reference for a stock amp for mods to not come up with the false idea that everything I did was an improvement.
As Jeff was saying sometimes it's frustratingly not.
My original stock Fisher is now no longer stock. It was the amp that caught fire and melted an output transformer. My modded vintage amp in main system has long ago passed the stock vintage amp.
The Fisher was cathode biased. My tech guy who builds tube amps and repairs amps from all over Canada and the U.S.. A lot of expensive gear. Just love visiting him to see what is in for repair!
He changed the cathode biased amp to fixed bias. He did not like the circuit. He thought unstable. No argument here! (Chew up tubes catch fire the only thing it did well was sound great and very quiet)
A repair mans point of view will be different than ours.
I can not comment fully the change in sound but for sure sounds different. Technically the amp already running much cooler and seems much more stable!
So far the amp sounds stable and cooler, like it is running. The 4 Solen caps I suspect not helping either. Artificial sound. (Grainy that I am not used too)
It is my new project amp to see if I can push it passed my best modded amp.
My gut feeling is the phono stage is going to be much quieter. The one area I have not been super thrilled with. Phono stage was too noisy on other vintage amp. (Jupiter caps helped immensely there)
I have no idea of the differences in fixed vs. Cathode biased for sound?
I do have to say I am wayyyy more confident that the amp is stable!
My modding ability is extremely limited to part for part replacement, and a set of ears.
Now back to following Jeff's blog and his excellent crew!