Bogner Ecstasy Classic Tube Layout

[joafink2]

Anybody have the tube layout for this amp?

I have one that’s killer sounding. But the clean channel is having volume swells. Thinking it’s a bad preamp tube. Anyone know which preamp tube (or tubes) are correlated with the clean channel?

 

[101B /^/]

See pics for tube layout from the online xtc manual (2004). Technically the manual's for the 101B but I’m guessing tube layout is the same.

 

[101B /^/]

Updating to add a nice tube layout of the xtc I discovered through the search function. This one shows what each triode’s function is in the preamp. Thanks to the original poster who shared the info (see image below) - I’ve found it quite helpful to pick apart the nuances of the xtc’s preamp section. I’ve tried a small handful of various preamp tubes including some nice nos tubes (Mullard/Amperex, RCA,etc). In the end, it seems to be chinese preamp tubes at V1,V2,&V3 for me thus far - no other tube I’ve found has the richness of the chinese tubes in my amp. I sometimes use a 12AU7 at V6 for the clean channel and a Sylvania 12AT7A at V5 (phase inverter) seems to have found a permanent spot in my amp because somehow every channel sounds better to me - more usable gain on CH3 especially. I don’t seem to hear much difference swapping out tubes at V4 (loop). I’ve also found that just because a preamp tube is noisy in one spot, it doesn’t mean it will be noisy in every spot. It’s definitely worth a try in other positions before pitching what could be a perfectly good tube.

Ironically - I’ve been using a pair of old =C= power tubes that don’t perfectly match while rolling through the preamp. I also have no clue whether the 12AT7A I have at V5 (PI) is ‘balanced’ or not. My amp’s never sounded better.