12AX7 Specification

12AU7 Specification

Not all tubes are created equal.

We cherry picked the best tubes from the production for the US market. Our US engineers further tested these selected tubes and classified them into 3 grades:

Pricing:
Grade A (top 10%): $100 per unit with 30 days warranty, $18 extra for one year warranty.
Grade B (top 25%): $80 per unit with 30 days warranty, $18 extra for one year warranty.
Grade C : $59.99 per unit with 30 days warranty, $18 extra for one year warranty.
Factory bulk (unrated): $49.99 per unit with min order of 10 units.

User Experiences:

Received Date: August 8, 2011 I just wanted to thank you and give you feedback on the really excellent sounding pair of Sophia Electric 12AX7 tubes that you sent out to me. I have read some hearty recommendations on your tubes from other folks who are very satisfied so I wanted to try your tubes myself. I own and have used both NOS and modern production tubes in my preamp. It is a high gain preamp and tube noise is a factor for me. In addition to the sound I think these might be the lowest noise tubes I have ever used in it. The tone is excellent and the tubes do everything right from high to low. Thank you again. I am very pleased. Take care Jim

Audiogon Forum Posted Date: April 13, 2011 I've tried all manner of 12AX7's in my Hovland HP-100 phono including a number of NOS' and the overall best that I have found so far are the Sophia Electric (have not tired the Psvane yet though). Of course get their "A" grade for best results. Of course, YMMV! By Stickman451

Received date: April 4, 2011 I was very impressed with your 12AU7's I bought from you. I just tried them in an Eastern Electric Mini Max DAC going straight into the Baby Amplifier I also bought from you and too my preamp out of the equation to hear more clearly the tube changes. This particular DAC has (1) 12AU7 in the output stage. I had used a rare NOS Siemens Silverplate 12AU7 and a Mullard Longplate double crossbar D getter with the K61 etched date code etched in the glass that I have on loan to try out. The Siemens is very clear, very open, and very natural sounding and very balanced from top to bottom. The Mullard is rich and warm with a big soundstage, fuller sounding voices and instruments with very vivid overtones with excellent air around each performer, and more powerful bass. The Sophia Electric 12AU7 took all of the above virtues and combined it into (1) tube maintaining the excellent clarity and naturallness of the Siemens, but also expressing musical overtones, soundstaging, vividness of the performers, and powerful bass and excellent dynamics of the Mullard. The above opinion was confirmed by a close friend who joined my in my listening test and has built his own tube amplifiers for some time and, whenever possible, also favors the Sophia Electric Tubes. Well Done! Dr. Glenn A. Thomas, M.D.