IanBallard
New member
OK... so I bought a Tung-Sol to spice up my preamp in my Crate Vintage Club 60 2x10. I realized that the effects loop tube was a 12AU7 which I want for my PI and since I don't (usually) use the FX loop, I thought I'd swap it in for ****s and grins. OK...
If you are looking at the circuit from the bottom (it's a combo) from the back, it looks like this:
[input tranny] (tube)--space---(tube) (tube) (tube) [output tranny]
The tube closest to the input was hotter than the rest, so I assumed it was the V1 tube, BUT that tube is further away than the rest and I know PI's are worked very hard, so I thought maybe the circuit had them in the opposite orientation. I swapped in the UA7 at the last tube by the output and the sound was very low, tinny and almost non-existent. Soooooo, I tried the opposite side and same thing. Obviously the tube is shot...
However, I discovered a Groove Tube AX7 in the last slot by the output tranny and stuck it in the second to last slot. OK.... Putting the Tung-Sol in the (assumptive) V1 slot, made all the harshness go away that the stock Sovteks were delivering, making me rethink needing new output tubes or really doing any work on it right now.
Just wondering, am I correct (having no access to a wiring diagram or schematic) that the order is:
[input] (V1)----space----(V2) (V3) (PI) [output] ??
If you are looking at the circuit from the bottom (it's a combo) from the back, it looks like this:
[input tranny] (tube)--space---(tube) (tube) (tube) [output tranny]
The tube closest to the input was hotter than the rest, so I assumed it was the V1 tube, BUT that tube is further away than the rest and I know PI's are worked very hard, so I thought maybe the circuit had them in the opposite orientation. I swapped in the UA7 at the last tube by the output and the sound was very low, tinny and almost non-existent. Soooooo, I tried the opposite side and same thing. Obviously the tube is shot...
However, I discovered a Groove Tube AX7 in the last slot by the output tranny and stuck it in the second to last slot. OK.... Putting the Tung-Sol in the (assumptive) V1 slot, made all the harshness go away that the stock Sovteks were delivering, making me rethink needing new output tubes or really doing any work on it right now.Just wondering, am I correct (having no access to a wiring diagram or schematic) that the order is:
[input] (V1)----space----(V2) (V3) (PI) [output] ??
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