Ordered for the effects loop in my Crate VC6212 and it cleaned up a microphonic issue with my boost. As much as I do not want to like Groove Tube products I can say I have always been happy. Worked out great for my application and fixed the issue with the amp.

Bought this tube to replace the stock offering which came with the Bravo V2 headphones preamplifier. Everyone said it was a far better tube than the one it replaced, and I changed to this one as soon as the Bravo arrived and never turned it on with the original, so I really have nothing to compare it to. All I can say is I burned it in for about 50 hours at relatively high volume, playing a range of music from Miles Davis, to Jimi Hendrix, to Shastakovich, to Katie Perry, to Tibetan Singing Bowls. The sound now from this combination through my V-Moda Crossfade headphones is delicious beyond words. Tube amp lovers talk about a variety of tubes, each with their own afficianados. I don’t know about all that. All I do know is that I love the sound of this tube and the pre-amp

Fixed my hum I was getting in the preamp section. I use this in a Fender Twin Reverb ’65 Reissue. I play exclusively through the second channel, so I put it in the second slot and good to go. Slam dunk.