AU7's/AT7's?

[JTyson]

Have you guys swapped these for 12AX7's for a lower gain?
What kind of results did you get?

 

[fusedbrain]

NOS 5751's have worked the best for me. Drops the gain, but does not change the tone or feel. I haven't had much success with AT7's or AU7's, as they seemed to change the amp too much. They did work kinda ok in the 3rd/4th gain stage but not great in V1. The 5751 sounded the best and it worked for any gain stage. And the NOS 5751's sound SIGNIFICANTLY better than the CP stuff.
I like these:
http://www.thetubestore.com/Tubes/12AX7-ECC83-Tube-Types/JAN-GE-5751

 

[JTyson]

Interesting, I appreciate the link
Been thinking about trying one, looks like the 5751 would be the ticket. My thinking was the opposite of what was stated, never occurred to me an AT7 or AU would thin it out.
Just kicking around ideas, thanks mate!

 

[fusedbrain]

No problem
5751's are great tubes!
I know our very own Ventura is a fan of the JAN-GE and JAN-Phillips in V1 of a Bogner Twin Jet.
Wouldn't be surprised to see him chime in here any minute now.....
Good luck with the tube swapping

 

[Deadpool_25]

I have a Peavey Invective and was thinking it maybe has a bit too much gain. I was wondering what tubes might be good. Those 5751s might just be worth trying. I don’t want to mess with the sound of channel 1 if I can avoid it, but wouldn’t mind decreasing the gain on channels 2 and 3. Any tips on which specific tubes to replace if I go that route? I’ve never messed with preamp tubes and am not too familiar with their names (V1, etc.).

 

[fusedbrain]

I have a Peavey Invective and was thinking it maybe has a bit too much gain. I was wondering what tubes might be good. Those 5751s might just be worth trying. I don’t want to mess with the sound of channel 1 if I can avoid it, but wouldn’t mind decreasing the gain on channels 2 and 3. Any tips on which specific tubes to replace if I go that route? I’ve never messed with preamp tubes and am not too familiar with their names (V1, etc.).

I've done something along these lines with an EVH5153 stealth, where I only wanted to tone down the red channel.
Without having access to the schematic, you could try pulling the pre amp tubes, one at a time, and see if you can find a scenario where channel 1 still works, but channel 2 & 3 doesn't. Change that tube to the 5751.
Before pulling a tube, turn off BOTH power and standby switches, and wait for the tubes to cool down. You need to turn the amp completely off to turn off the heater circuit. It's not a good idea to pull the tubes while the heaters are on, and the tubes are far more fragile when they are hot. Pull ONE 12ax7, and turn the amp back on and see how the amp functions.
If you can't find a scenario where channel 1 works, but 2 & 3 don't, then just swap the 5751 into the different locations and see if you can get a result you like. Do NOT remove any power tubes and run the amp.
Also, V1 just means the first gain stage, and is usually closest to the input jacks. It's also usually common to all the channels in the amp, but who knows what Peavey is up to with the invective.
I looked quickly for a schematic for the Invective, but couldn't find one. If you have one, or know where to find it, post a link and I could give you more specific suggestions as to which tube to swap out.

 

[crankyrayhanky]

Here's some 5153 info with 12au7 taming the Red; it works really well!
viewtopic.php?f=3&t=187420&p=2092205&hilit=12au7#p2092205

 

[Deadpool_25]

I have a Peavey Invective and was thinking it maybe has a bit too much gain. I was wondering what tubes might be good. Those 5751s might just be worth trying. I don’t want to mess with the sound of channel 1 if I can avoid it, but wouldn’t mind decreasing the gain on channels 2 and 3. Any tips on which specific tubes to replace if I go that route? I’ve never messed with preamp tubes and am not too familiar with their names (V1, etc.).

I've done something along these lines with an EVH5153 stealth, where I only wanted to tone down the red channel.
Without having access to the schematic, you could try pulling the pre amp tubes, one at a time, and see if you can find a scenario where channel 1 still works, but channel 2 & 3 doesn't. Change that tube to the 5751.
Before pulling a tube, turn off BOTH power and standby switches, and wait for the tubes to cool down. You need to turn the amp completely off to turn off the heater circuit. It's not a good idea to pull the tubes while the heaters are on, and the tubes are far more fragile when they are hot. Pull ONE 12ax7, and turn the amp back on and see how the amp functions.
If you can't find a scenario where channel 1 works, but 2 & 3 don't, then just swap the 5751 into the different locations and see if you can get a result you like. Do NOT remove any power tubes and run the amp.
Also, V1 just means the first gain stage, and is usually closest to the input jacks. It's also usually common to all the channels in the amp, but who knows what Peavey is up to with the invective.
I looked quickly for a schematic for the Invective, but couldn't find one. If you have one, or know where to find it, post a link and I could give you more specific suggestions as to which tube to swap out.

Cool thanks. I’m away from home but I think there’s a schematic in the manual. I’ll check when I get home.