Re-Bias for changing 12AT7???

[SteViL666]

Hello everybody!!!!!! :twisted:
I just bought a Randall V2 used from some guy that's had it for about a year, and I am really happy with it!
But I thought I should change the tubes since he's had it for a year now.
I put 3 tung sol 12ax7's and a 12AT7 Electro harmonix.
But I think it might be a different 12AT7 because it has like 2 extra letters on the tube (12AT7HW?)
Now the solid state side (clean & overdrive) sounds great and loud, but the Tube overdrive is like at 25% of the volume of the solid state and sounds terrible!!!!

So...I think that either you have to change that 12AT7 with the exact same type of tube..OR...the tubes I put are just BAD!

Please let me know what you guys think!!!!!!!

I really need my V2 sounding like a beast again!!!!!

thanx :lol:

 

[jmgman70]

Sounds like a bad tube.Just get another one just like the original if thats what you liked..

 

[SteViL666]

Thanks for the tip!
I will change the 12AT7 back to the original and if that doesn't help then the tung sol 12ax7's I put in there might've been fudged up too... even though they were supposed to be brand new, matched and balanced!!!!!!

anyway.. i'll let you guys know how it goes.

 

[jmgman70]

I don't know for sure but I would use the AT7 and not the AX7,unless it states somewhere in the manual,as i'm not to familiar with the V2.What I meant about the original was get a new one the same as the original,sorry for the confusion

 

[SteViL666]

Yeah exactly!
I ordered another EH 12AT7 just like the one the amp came with.
The 12AT7 tube I replaced it with was an EH 12 AT7WT...it wasn't exactly the same type. I think that's why the volume got drained out.
I will see when the new one I bought arrives- the same as the original Electro Harmonix 12AT7.

If THAT doesn't help, then maybe the 3 tungsol12aX7's were bad.
That is why I ask- Do you have to re-bias the amp to change the AT7?!?
Or what?

Anymore insight is definitely appreciated!!!!!!!!!!!!!!!

RANDALL KICKS BALLS!!!!!!!!!! :evil:

 

[jmgman70]

Didn't know there were three 12AX7s in there to.It could be one of those to,so if you have a known good AX7 you can rotate it in the mix until you find a bad one!I don't think that amp has power tubes so no need to bias!

 

[SteViL666]

Yeah....the 3 preamp tubes ( tungsol 12ax7) were fine after all.
The electro-harmonix was a 12AT7WC EH and that is why the sound was drained out of the tube O.D.
I just replaced it with a electro-harmonix 12AT7 EH and it sounds awesometastic :!: