Spatial Audio Raven Preamp

@jc4659 I am using the Shuguang flagship WE6SN7plus in mine.   They are finally back in production.  That will be the base tube going forward.  The hand selected Linlai E-6SN7 is more expensive and the upgrade option.  I would say they are both just superb tubes.  The Shuguang is a bit warmer and has almost all of the detail and air of the Linlai.  The Linlai has a tad more air and is a tad more neutral.  That isn't to say the Shuguang is syrupy or the Linlai cold.  You would be happy with either, but if  your system is a bit bright, then pick the Shuguang, and if your system could perhaps use a bit more air, then use the Linlai.  Both are just wonderful tubes.

You have to realize that I have a Lampi Pacific 2 DAC, the matching Blackbird 300b amps, and some amazing open baffle speakers so my system allows me to hear even subtle differences between tubes.  If you had a more pedestrian DAC and amp and speaker in the chain, then the differences would be masked.  The point is that the Raven is totally transparent to my ear and will let you hear everything in a way that most preamps cannot.  My 2 cents, and yes, I am totally biased since Lynn and I designed it!

I have had the pre-production "shoe box" 300b monos as well as the Raven for several months and have owned all Don's earlier preamps and the Kootenai.  They mate very will with my Cube Audio Jazzon speakers.  Outstanding gear, no question.  

@terrapin77 Probably more than a few Don Sachs preamp owners waiting on the sidelines. No pressure!  Don't try to write a professional review, just your honest thoughts will do as it's all subjective anyway.

@donsachs My system might respond well to the Linlai tubes.

Yes, I’m curious too. Oddly enough, even though I designed the Raven in 1998, I never actually heard one until the Seattle show last June 2023.

Don and I agreed it was good to choose tubes that were (A) in current production from respected vendors with an excellent track record of reliability, and (B) offer the option of using classic vintage tubes for folks who want to do that. So no unobtainium surplus tubes like 12SN7, ancient 101D’s, or using power-tube DHT’s in a preamp stage that require exotic anti-microphonic isolation systems.

We want keep it simple and focus on the most linear circuit possible. The entire signal path is transformers, wire, and vacuum tubes, in a fully balanced configuration similar to Western Electric line amplifiers from the Thirties. It’s actually rather difficult to "tune" subjectively because there isn’t much you can tweak.

One thing I can say: when you get rid of the last coupling cap in the circuit, surprises await.

One of the points of inspiration: the late-Twenties Western Electric Model 43A amplifier, used in the WE Mirrophonic theatre systems.