I thought about changing them on mine. I've owned this one for probably 15 years but I have other preamps and mainly use this one for overheads and bass DI. I'm not sure where to get the Jensen transformers anymore. PreSonus used to have them but I doubt they still have parts like that for a legacy product. It sounds pretty good as is for my uses though.
Soundcrafts are awesome. I'll gladly take the blame for that. Which Soundcraft did you get? I've been wanting a Series II, the old one from the 70s but I've never used a Soundcraft that didn't sound great.
I think it is one of the first standalone mic preamps I ever purchased. I have always thought it has a nice silky sound and now I've found more uses for it.
