One pair of Sophia Electric 91-05 300B single ended output transformers in new condition. Other 300B OPT models at lower price points available at Sophia Electric's website www(dot)sophiaelectric(dot)com
(845/211 output transformers are also available upon request).
Designed by Dr. DWU and Richard Wugang. Sophia Electric made these output transformers in-house in Virginia. Magical sound, very musical with sense of space and time. Excellent bass extension and airy yet creamy highs. Full bodied sound, a lot of weight and dynamics.
Sophia Electric obtained exceptional high frequency extension through more advanced winding method on traditional EI core, while other makers have to use C core. Some audiophiles complained C core lack of tube amplifier mid range flavor and magic(solid state like and bright). You really have to audition Sophia Electric OPT to get EI core's mid range magic and creamy high frequency.
Sophia Electric vs. Audio Note
300B Single Ended Output Transformers
date: February 1, 2012
Dear Sophia Electric:
After 200 hours, the Sophia 91-05's have opened up nicely. They may continue to improve with additional time so bare that in mind when considering these comments.
My wife, an orchestra conductor and I have done listening comparisons between the Audio Note 300 HiB C core transformers (Audio Note Transformers-73134 TXO-300-1-I-H306-H306-FC: $1127 for one transformer, or $2254 for one pair) and the Sophia's (91-05 300B transformers: $1000 per pair). We have concluded that one is not better than the other. The difference is in presentation.
Both have very good Low end and hi end frequency extension. The AN's are more detailed and seem to bring out solo instruments a bit more. The Sophia's seem to present the music as a "whole" not emphasizing any one part more than another. My Wife likes the Sophia's just a bit more and I liked the AN's just a wee bit more. She felt the Sophia presentation was a bit more like what she is used to hearing in the concert hall and I liked the bit of additional detail that the ANs have.
With my Audio Note AN-e LX HE speakers we both agree that there was a bit more synergy with the AN OPT's.
We chose the Sophia transformers baring in mind they are less than 1/2 the cost of the AN's and they are likely to continue to improve. Also since I am in breadboard mode, I can adjust a cap here or there for some presentation changes.
James, New York
Read the original discussion before the user sent in the above review:
See Sophia Electric OPT designer's interpretations of the above feedback on the Sophia Electric and Audio Note OPT sonic differences at www dot sophiaelectric dot com.
Information about Sophia Electric output transformers:
91-01 OPTs are being used in Sophia Electric 91-01 single ended mono-block 300B amplifiers. Please see review below:
Positive Feedback Review: "...The Sophia Electric Model 91-01 300B mono amps are audiophile dream amps, they have great sonics top to bottom, bass articulation that is the best I've heard, and the SE 91-01 nails all of the nerdy audiophile things like soundstaging, imaging, sense of space, and transparency in such a beguiling way that even music lovers that don't give a rat's ass about audiophile-type sonics will appreciate its prowess.
I recommend these amps heartily, and I'd give them my normal 'two thumbs up' endorsement, but that just wouldn't capture what these Sophia Electric Model 91-01 300B mono amps are capable of, so I've invented a new rating, the 'two hard nipples up' recommendation, which is the highest award I've given out to date. ..." ––– Jeff Day
9101 is the vintage winding method (like vintage WE) for mid range magic with excellent bass and excellent high frequency. Much better than most Japanese, European and US output transformers in the market. Great for all 300B tube in single ended circuit for output 8-10 W. It is the output transformer choice for Sophia Electric 91-01 mono-block amplifiers.
9103 combines the best vintage sonic characters and superior(even better than 91-01) high frequency extension (great for 91 amps that use 310A or 6J7 family of driver tubes).
9105 is the OPT choice of the flagship model of the Sophia Electric 91-05 300B amplifier, very exotic. Great soundscape with 3D dimensions of space and time. Sound stage is way wider than the two side walls and sound stage is deeper than any other brands of OPT in my transformer collections. Ultra resolution without brightness, ultra liquid with first class dynamic and just perfect path and speed. It does everything right!!! Great bargain for only $1000 (Anyone listened to it earlier thought the price tag should be $2000/pair). With authentic vintage WE core and exotic wires and winding method, please email inquire.
Store location for local pickup:
1952 Gallows Rd, Suite 214, Vienna, VA 22182
91-05 OPTs user experience:
Thank you for the help with hooking up the 9105 opt yesterday. They sound spectacular! Your sonic description is very accurate. Liquid, deep, wide and spacious. I'm very pleased.
Ted, Washington State
User experience from Sweden:
I have been auditioning these Sophia Electric 9101 OPTs for a little more than a week and two words that constantly come to my mind are sweet and spacious. They do really have a "magical" tone inside a "timeless" space if you so want it to be. The sound is quite seductive with nice dynamics but never sounds harsh in any way. It's nice to have the tonal balance these OPTs have that takes away a little bit of the otherwise for some people too analytical and clinical sound of the 300B. I'm using a pair of 97db speakers and there is really a lot of pressure (dynamics) and body in the music, very detailed and well articulate for sure.
Thank you and I wish you luck with your company...
Sonny/Chris from Sweden
User experience from USA:
When I purchased a pair of your Sophia Electric 9101 opts for my 2A3 amp back in March, I really didn't know what to expect. I have two other tube amps, a push pull and a SE. Being an avid stereo lover over the last thirty years, it has been my hobby to check out all the high end audio dealers regularly to keep up with the sound that I could never afford. The only downside to this hobby is going home to your own system and not be able to enjoy it for weeks until your ears readjust to your own system. When the highly recommended amp builder I chose called me to let me know that the 2A3 amp using Sophia Electric 9101 opts he had wired up for me was on its way and told me in his opinion it was a big step up quality and sound wise from the usual triode amps he builds using Hammond, MagnaQuest and Silk opts and that it was at least as good and maybe better than any he had heard using Hashimoto's opts, I wanted to get excited but knew better having been let down before! Well I am proud to say now that I have had time to go through most of my music collection I am still overwhelmed! I am hearing sounds and nuances that I have never heard on all of my old favorites. The clarity and definition in the music is amazing! It is so accurate and the sound stage is just like being there live. My modified Khorns have never sounded so amazing! I can't wait until I can replace my RCA 5Z3 rectifier with the Sophia 274 meshplate and then replace my vintage RCA 2A3's with the Sophia princess 2A3's. I am happy to say my new hobby is staying home and listening to my own stereo! THANKS So Much Sophia Electric!!! T.H. from North West Okla
Amplifier Manufacturer's review/feedback
Tube Audio Lab(TAL) in California has purchased many pairs of Sophia Electric 9103 OPTs. Here is the user experience found from TALwebsite:
Sophia Electric output transformers:
Core: vintage Western Electric core(from WE chokes) and modern core mix,
Wires: US made OFC
Natual fiber(cotton) made papers and non-magnet stainless steel screws
Hermatically potted in a metal case.
Sound: excellent high end extension, seductive mids and good bass. Magical! at least in my amps.
Very close to real Western Electric sound.
My user experience:
Sophia Electric OPTs do actually sound very nice. I mean VERY nice. I honestly can't tell if these are significantly better sounding than the Hashimotos, if at all, since I don't have an amp with Hashimoto OPTs to make the AB comparison. But I get the same goosebumps when I hear these Sophia Electric made WE-core OPTs as I did when I auditioned Paul's amps (Hashimotos OPTs, $800 per pair + $200 shipping from Japan). It's all there- excellent high end extension, seductive mids and good bass. Mostly importantly, they are very natural sounding and musical. I am spinning some Jazz records as I am typing this and I can't remember for how long the amp has been on. It's been playing music for hours, but I didn't notice it(time flying quickly) because the sound is so comfortable. Hope I remember to turn it off before going to bed! Will I recommend these for future builds? Sure. After all, shouldn't a WE91A deserve WE sounding OPTs? TAL(Tube Audio lab)
Shipping & insurance is about $18 in the US.