[wilsynet]

Regarding the Ultra SL versus the T8, which one has the lower noise floor?

Also, what are their respective input and output impedances, and how much gain do the preamps add?

Thanks,

Wilson

[sueata1]

Sounds like a ? for The Man,,
You might want to try emailing Frank thru his Website AVAHIFI.COM

Happy listening,,,
Mel

[avahifi]

The input impedance on all AVA preamps is 47,000 ohms, a pure resistive load.  The output impedance of the Ultra hybrid and our solid state preamps is 560 ohms, set by a series resistor.  The output impedance of the T8 vacuum tube preamp is about 1K ohm.

The noise floor on all units is in the range of 1-2 mV unweighted from all circuits.

Voltage gain is 20 dB on all line sections, 40 dB on all phono sections at 1K Hz, varying up and down from that to follow the RIAA curve.

Note that these numbers are pretty much industry standards, no surprises.

Regards,

Frank Van Alstine

[I.Greyhound Fan]

Wilsy, go with the Ultra.  I got a chance to audition both and the Ultra has better transparency, detail and a much wider sound stage.  It also has better bass and treble.  That's not to say the T8 was bad.  It is a very nice sounding preamp and it definitely has a warmer sound.

[martyo]

Here is a link to a previous review of both preamps by BrianM who owned both and is pretty adept at expressing himself. http://www.audiocircle.com/index.php?topic=41095.0

[I.Greyhound Fan]

Looks like Brian M and I said the same thing about the Ultra preamp but he put it more eloquently.  I would have to agree with that review after auditioning both the Ultra and T8 in my home with a parasound Halo A21 amp, magnepan MG1.6 speakers and using both the 840c CDP and Ultra DAC.  By the way, I also auditioned the Insight preamp and DAC  as well as the T8 DAC.  All are excellent and have their strengths.