preamp tube question

[imzadimark]

Not sure if this is the right category or not??
Ok I only have 1 electro harmonix 12au7. Would i better served to put it in my clean module or the PI of my rm100?
Thanks in advance for any suggestions.
Mark

 

[drewiv]

Not sure if this is the right category or not??
Ok I only have 1 electro harmonix 12au7. Would i better served to put it in my clean module or the PI of my rm100?
Thanks in advance for any suggestions.
Mark

There's many more people much more qualified to answer this question, but I would think it would be better served in a clean module. In my completely uneducated opinion.

 

[Slashpepper]

Just to clarify, presumably you already have tubes in there already but have one new replacement?

What are the current tubes in the positions currently and how old are they?

 

[imzadimark]

Sorry...let me clarify. I bought the rm100 used on this very forum. I have no idea what kind of pre tubes are in the amp. The clean just has the stockers. I bought a 12au7 (they only had 1, and didnt have a 5171) to replace in the clean mod, but was reading that the pi is super important, so now im wondering. I also bought a eh 12ax7 just for shits and gigs, to try out.

 

[Mattfig]

Sorry...let me clarify. I bought the rm100 used on this very forum. I have no idea what kind of pre tubes are in the amp. The clean just has the stockers. I bought a 12au7 (they only had 1, and didnt have a 5171) to replace in the clean mod, but was reading that the pi is super important, so now im wondering. I also bought a eh 12ax7 just for shits and gigs, to try out.

If it were me personally I would use it in a clean mod V1...It would work in the PI as well...Try it in both and see which you like...A PI should be close to matched but it's kinda cool to have a slight mismatch anyway... Also a 12AU7 is pretty low output which will still work but I have doubts as to how well...I think 5751s are so popular in PI 'cause they're less gain than a 12AX7 but not a huge difference...

 

[m0jo]

You can try either and see what happens, I think that would be the best advice.
Besides that it's a matter of opinion and it's better to form your own

You can use it in the Clean mod to tame it a bit if your pickups are overdriving it.
You can use it in a gainy mod to reduce the gain too.
You can use it in the PI too, that should make it a tad clearer, but will also make your gainy mods less agressive.

IMO I wouldn't use it at all.
I've tried a 12AU7 in all those positions, and I don't like the reduced gain and change in dynamics.
Because the gain is reduced (even in those clean stages) it loses compression, an important aspect of why we like tube amps so much.
So for me it didn't work, but maybe it will for you so try it out!

 

[imzadimark]

Thanks for the advice everyone. I was planning on trying mutiple things, but I'm on a time crunch today. Gig tonight and not much time between work and soundcheck :wink:

 

[Mattfig]

I'm pretty much with m0jo on this...Trial and error is best as tone is totally subjective...

But I also don't like 12AU7s for the same reasons...It takes too much life out of your tube tone...But hey, some people like that dullness it adds... :twisted:

 

[m0jo]

But hey, some people like that dullness it adds... :twisted:

Haha, great comment.
It's true though, some amps can be a bit too "lively" for some uses, so there it can be a fix, but for me it takes away from the feel.