[RPM123]

I can attest to the quality and sound of the EL34's (pre blue glass) in my Ultravalve amp. Been using them for over a year now with no issues and they bring the Ultravalve  up at least a notch or two in sound quality. There is no comparison to the stock tubes! Not cheap, but you get what you pay for.

https://positive-feedback.com/audio-discourse/sexy-blue-tubes-the-sophia-electric-el34-st-and-aqua-274b-vacuum-tubes/

[tdinut]

Thank you for posting the review.