
Fiesta Red
Well-known member
Has JJs in there now -- starting to sound a little bright (even for a plexi). Might need to have the bias checked.
What tubes would you use?
What tubes would you use?
I use RFT in V1 for the SLO, and did in the JCM800.RFT in V1 is what I had in mine. Trims a little off the top
JJ E34L, or KT77. JJ 6CA7's are a bit warmer, but I find them less aggressive. Another great tube, (and warm), is the Tungsol EL34B. Punchy too.Has JJs in there now -- starting to sound a little bright (even for a plexi). Might need to have the bias checked.
What tubes would you use?
I have a couple of their CV4004's that came out of an amp I bought used. They are very quiet, warm and fat. And expensive...FWIW - I have had very good luck with the Genalex Gold Lion 12AX7 to warm up the top end on bright amps. Pricey, but really nice sounding.
Sounds like a preamp tube. V1?I notice it has lost about 10 percent of its gain also, in addition to being brighter.
They’re pretty readily available on eBayAnyone have an RFT they want to part with?
In a recent interview Dave Friedman stated in 2025 he likes to run a JJ in V1 and Chinese 12ax7's in V2 and V3. He stated the issues he is seeing mostly is microphonics in current production preamp tubes when selecting for V1.
Usually on plexi amps V1 is the preamp tube the farthest from the power tubes and closest to the input jacks and it looks like that applies on the Plex as well.
View attachment 402975
My plexi/superlead go to preamp tubes regarding new production preamp tubes are Tung Sol for V1(sound similar to NOS Sylvania, V2 and V3 8th generation Ruby AC5 Chinese. Just pick the power tubes you like.