12at7 tube selection

[pbman1953]

Do any of these tubes have better reputation over the other?-


GE- ECC81/12At7


RCA- 12AT7


GE 6201

[HotBluePlates]

Do any of these tubes have better reputation over the other?

Not really.

Whether any of them sound "better" is going to depend mostly on the circuit, and the Ear of the Beholder.

[pbman1953]

It's for the phase inverter in a bass amp

[HotBluePlates]

It's for the phase inverter in a bass amp

That phase inverter is likely inside the feedback loop of the amp, so the 12AT7 shouldn't contribute much to the sound (unless the output section is distorting, nullifying the effect of the loop).

[TitaniumValhalla]

I may just be the unluckiest guy in the world, but I had crackly noise issues with three different NOS GE JAN 12AT7’s from two totally different production years in the phase inverter position on an AB763. A dirt cheap new production EHX tube worked fine there so I assume something about the design of the GE did not like that position in that circuit.

[HotBluePlates]

I may just be the unluckiest guy in the world, but I had crackly noise issues with three different NOS GE JAN 12AT7’s from two totally different production years ...

I think you must be unlucky.   

I just checked, and I have 60 12AT7s from RCA, G.E., American Tung Sol, and British Mullard with a few Amperex and Telefunken sprinkled in.  I haven't encountered any crackly noise issues with any of them.

[pbman1953]

Please help me understand something, does the sound signal go through the phase inverter tube?


Besides the phase inverting , does it play any other part?

[HotBluePlates]

Please help me understand something, does the sound signal go through the phase inverter tube?

Yes.

Aside from switching logic circuitry and perhaps status indicator lights, pretty much everything in a guitar/bass amp is "in the signal path" (no matter what an Internet Guru says).