User Experiences: Sophia Electric Signature 91-01 300B Single Ended Mono-Block Amplifiers

Hi Richard,

I've been meaning to email you about your Signature 91-01 300B monoblocks. Let me say, I am very very impressed with these amps. They look as beautiful as they sound. I absolutely love their vault like construction and aesthetic. The picture on your website does not do them justice. You should post some studio quality pictures, they deserve it. I smile every time I look at them. The sound is just what I was looking for, that glorious 300B richness while still having the modern bandwidth. You pushed the envelope of what 300B SET's are capable of, bass that is taught and deep and highs and mids that cannot be matched by any other topology that I know of. There isn't a genre of music that doesn't sound good through these. Totally enjoying them. They are so revealing of upstream quality, I'm now upgrading cabling.

Well done, Sir!

Thank you,


Dear Sue and Richard,

I wanted to write you to let you know how much I am enjoying my 91-01 300B signature amplifiers.  If you remember I had several amplifiers on hand when I was evaluating my next purchase, and the Sophia’s showed a realism in vocal reproduction that stood out from all others.  My listening preferences lean towards vocal dominated performances from the 1940 to current artists (everything from Billie Holiday to Norah Jones and Leonard Cohen) , and these amplifiers bring out detail and nuance from songs I have listening to for many years. Congratulations on a great product!

Mike D.

North Carolina, USA

Hello Sue and Richard,

I want to take a moment and thank you for building wonderful sounding and beautifully built 300B mono amplifiers! We manufacture a high sensitivity line source loudspeaker system (Arion Audio Apollo System) and needed high quality mono amplifiers for our showroom. After doing our research we chose the Sophia Electric 91-01 Signature 300B Single Ended mono amplifiers.

I purchased the pair of your Sophia Electric 91-01 Signature 300B SE mono amplifiers about six month ago and couldn’t be happier with their performance. The sound and performance of the main system in our showroom which includes our new Arion Audio Apollo speaker system and the Sophia Electric 91-01 Signature 300B SE mono amplifiers have impressed everyone who has heard it. The system sounds powerful, yet detailed and delicate. The amplifiers have impressive high frequency extension but never sound harsh or piercing. The ever-so-important low midrange / upper bass is well articulated and musical. It’s easy to follow bass lines. We will enjoy our pair of Sophia Electric 91-01 Signature 300Bs for many years to come.

I must add that working with both Sue and Richard has been a great experience. Thanks!

Mike Kalellis 
Arion Audio