Big 12ax7 fun

Brick · May 5th, 2006, 11:23 PM

On the advice of Teletubby, who I just bought my MMB from, I went through my tube stash and picked out all my 12 ax7s that weren't currently in amps. Much to my surprise, I had no less than 10 different tubes. Since the MMB has only one 12ax7, it's easy to swap out the tubes. I got out ol #1 ( VZ flatpole bridge, Lollar P 90 neck) and randomly started swapping tubes. By the seat of the pants feel ( no scientific method here), I put anything I wanted to keep on playing in one pile, and anything that was ho hum in another. Of course I sneaked a peek at what they were going in, but still used my subjective judgement in evaluating the tubes.

What I found was that to me, every tube labled Made in Russia, sounded pretty much the same. These ranged from Ruby, to Electro Harmonix, to Sovtecs to Mesa, and Groove Tubes. I suspect they were all Sovtecs. None made my favorite pile. They weren't bad at all, and they tended to have more gain. The amp was at 5 and at that volume the amp was into distortion mode pretty heavily.

What did I like? Tubes that in my mispent youth and middle age I had pulled from amps I had just bought on the misguided assumption they were old and needed changing. Zenith, Amperex, Phillips, GE. These all were very similar to my ear. The amp was not distorting quite as much, seemed more focused with a tighter bottom end, and much to my enjoyment, brought out more pinched harmonics. You know that really high end harmonic that remaines when the rest of the note tapers off. Pinched harmonics are ingrained in my style now, and I'd never heard them jump out quite as much. The other thing I liked was how the range of distortion gotten by varying pick attack seemed to me to be controlable over a broader range, where the Russian tubes had a much narrower range from slightly dirty to really crunchy.

I have some real Mullards in my Bassman and will have to try one of those as well as the Groove Tube Mullard wannabes.

The 12ax7 labeled Made in India sounded like a bad Chinese tube.

Anyway, a highly amuseing way to spend a late Friday afternoon.

May 5th, 2006, 11:23 PM	#1 (permalink)
Brick Tele-Holic Join Date: Mar 2003 Location: San Jose Age: 58 Posts: 793	Big 12ax7 fun On the advice of Teletubby, who I just bought my MMB from, I went through my tube stash and picked out all my 12 ax7s that weren't currently in amps. Much to my surprise, I had no less than 10 different tubes. Since the MMB has only one 12ax7, it's easy to swap out the tubes. I got out ol #1 ( VZ flatpole bridge, Lollar P 90 neck) and randomly started swapping tubes. By the seat of the pants feel ( no scientific method here), I put anything I wanted to keep on playing in one pile, and anything that was ho hum in another. Of course I sneaked a peek at what they were going in, but still used my subjective judgement in evaluating the tubes. What I found was that to me, every tube labled Made in Russia, sounded pretty much the same. These ranged from Ruby, to Electro Harmonix, to Sovtecs to Mesa, and Groove Tubes. I suspect they were all Sovtecs. None made my favorite pile. They weren't bad at all, and they tended to have more gain. The amp was at 5 and at that volume the amp was into distortion mode pretty heavily. What did I like? Tubes that in my mispent youth and middle age I had pulled from amps I had just bought on the misguided assumption they were old and needed changing. Zenith, Amperex, Phillips, GE. These all were very similar to my ear. The amp was not distorting quite as much, seemed more focused with a tighter bottom end, and much to my enjoyment, brought out more pinched harmonics. You know that really high end harmonic that remaines when the rest of the note tapers off. Pinched harmonics are ingrained in my style now, and I'd never heard them jump out quite as much. The other thing I liked was how the range of distortion gotten by varying pick attack seemed to me to be controlable over a broader range, where the Russian tubes had a much narrower range from slightly dirty to really crunchy. I have some real Mullards in my Bassman and will have to try one of those as well as the Groove Tube Mullard wannabes. The 12ax7 labeled Made in India sounded like a bad Chinese tube. Anyway, a highly amuseing way to spend a late Friday afternoon.