The whole "zero negative feedback" design philosophy has always been interesting to me, and reading different designers and tech debate this for different reasons. "Distortion" vs "Musicality", etc. So what does it realy mean to different designers.
Seems Richard Vandersteen and Mike Sanders are on a similar page about this, and I read oup on it becasue way back during the early hears of the 2C speakers and onward there were a lot of Vandy speakers paired with QS amps out here in US-West.
Looking up specs for some of Mike’s stuff I could only find a few with up to 10db feedback used in only 3 amps, like Horn Monos used with super efficient speakers.
General Findings
"Quicksilver is known for minimalist, simple tube designs, they do not exclusively use zero-feedback circuits across their entire range."
- Zero Feedback Models: Several of their designs, particularly their headphone amplifiers and some monoblocks, are designed with zero feedback to improve musicality and reduce distortion artifacts
- Variable Feedback Levels: Quicksilver amplifiers, designed by Mike Sanders, often use low levels of negative feedback rather than none at all to optimize performance.
- Specific Examples:
- Horn Mono: Uses 10dB of feedback
- Mini Mono: Uses 20dB of feedback
- Headphone Amp: Explicitly designed with "no circuit boards or transistors" and implies a zero-feedback, simple circuit design
- Design Philosophy: The amplifiers are designed to be "tube-like" with high reliability, aiming for a balance between low distortion and high musicality
How accurate this is I don’t know. Interesting to read up on this more between different speaker and amp designers and what each of them believe.