I dont know what the impedance curve is on the Quest-Z, but if it is anything like the the Aerius, I would not recommend it. The SFS-80 uses very little negative feedback. While this really makes for a pure sound, it also creates a high output impedance, which means that coupling it with a very low impedance electrostat speaker will cause somewhat large fluctuations in frequency response. With the aerius, you would lose a lot of treble with one of these amps. (-5db at 15khz)
I have the SFS-80 and have used it in a couple of speakers.
See this article: http://www.stereophile.com/reference/810/index.html
On the other hand, with other speakers, these amps sound fantastic.
I have the SFS-80 and have used it in a couple of speakers.
See this article: http://www.stereophile.com/reference/810/index.html
On the other hand, with other speakers, these amps sound fantastic.