School me on preamp tubes. (please)

[Charliemills]

I know this has been asked before, but there's no longer a search function.

 

 

I have a Mesa rectoverb. It has 5 12ax7 preamp tubes. I've heard about swapping out 12at7 or 12au(y?)7 in amp's preamp slots. Is this possible with my amp, and what would/could be the preceived benefit?

 

Also, ECC83, just a 12ax7 labled differently in England?

[NaturalBornBoy]

Some guys prefer a 12AT7 in the P.I slot. If you replace a 12AX7 with a 12AT7, 12AU7 or a 5751, you'll start to notice a slight drop in gain.

 

ECC83 = 12AX7.

[Charliemills]

Some guys prefer a 12AT7 in the P.I slot. If you replace a 12AX7 with a 12AT7, 12AU7 or a 5751, you'll start to notice a slight drop in gain. ECC83 = 12AX7.

 

 

Is it relatively safe to swap a 12ax7 for a 12at7 or au7 on all amps?

[NaturalBornBoy]

 

Is it relatively safe to swap a 12ax7 for a 12at7 or au7 on all amps?

 

 

Yes they should unless specified by the manufacturer.

[thenakedarab]

Is it relatively safe to swap a 12ax7 for a 12at7 or au7 on all amps?

 

 

If I recall correctly not in all amps, though the particulars I don't remember.

 

5751 are a drop in for 12AX7 though. GE made some nice ones in the 70's and 80's that can still be had for relatively cheap, though they are a very snug fit in the tube sockets of my Mesa Tremoverb.

[TheEsupremacy]

I like a Tung-sol 12ax7 in V1. It's a brighter sounding tube. You'll notice it in your treble and presense.
I like the new Mullard 12ax7 in V1 for a darker, warmer, smoother tone.
I always go Chinese Shuguang Silver Dragons 12ax7B's (the real octo spacer ones) the rest of the way. They are actually kind of hard to find but you can get them at BOI Audioworks. I got great tubes and service from them.