Peavey Triumph 60

[Lostfollicles]

Has anyone else changed Pre amp tubes in a Triumph 60 from spec?

I have just changed V2 & V3 for 12AT7's and V4 for a 12AX7 including all the known EQ and nasty diode mods, the horrible Ultra/Crunch channels sound great and are far more usable!

Plus I'm very happy with my 6L6 to EL34 mod, albeit not a simple one with the PCB layout!

[Enzo]

I am sure people have, it is about the most common "mod" to do. Try a couple 5751's in place of those 12AT7s.

Did you try them one at a time?

Not sure about the V4 swap. the 12AT7 was used because of its higher current capability driving the reverb transformer.

[Lostfollicles]

I am sure people have, it is about the most common "mod" to do. Try a couple 5751's in place of those 12AT7s.

Did you try them one at a time?

Not sure about the V4 swap. the 12AT7 was used because of its higher current capability driving the reverb transformer.

Hi Enzo

I haven't got any 5751's but looking at the specs 70 is slightly higher than the 12AT7 at 60 and the Peavey has far too much grainy gain anyway for my tastes, it certainly has helped with taming the sounds to a far more usable type of distortion but if I had some 12AY7's or even 12 AV7's I would give them a try too!

I know Enzo you are the master of all things electronics so how else can I warm up that horrible grainy Crunch & Ultra channels? I know if I change the cathode caps to slightly larger values it would give me a warmer tone but then I don't want to get into motor boating territory!

Thank you in advance

[stokes]

I've always found the AT7 to be too "flat" sounding in any position but the PI or rev driver.Theres more going on than the 60 or 70 mu you mention.The AT7 has a much lower plate resistance than the AX7,AY7 or 5751,which I believe is the main reason for the "flat" or "dull" sound.I love the 5751,it lowers gain just enough but keeps the "sparkle".Another point is that if you compare a good AT7 to a good 5751 on a tester that measures mu you will likely find that neither matches the 60 or 70 the book says,so there really isnt going to be much difference in gain between the 60 and 70 mu.Pick up a good 5751 and I believe you will see the difference.I put the 5751 in the drive positions of Boogie amps and every one I've done it for were blown away by how much smoother and creamy the lead channel sounded.

[Enzo]

A 12AT7 is often chosen for its ability to handle higher currents, like a reverb drive transformer. the 5751 has a similar gain, but is better suited to circuits where 12AX7s are also used.. In any case, it is just something to consider, another tube in your arsenal. The small percentage gain difference is not spacious.

I might claim to be a master troubleshooter, but not a master of electronics.

You won't motor boat with larger cathode caps, but the ones in there probably already go as low as the guitar would notice. Warm it up by reducing the screechiness, ro;l off some highs or widen the coupling cap bandwidth here or there.