Power tube swap question

[misterwhizzy]

So I replaced and rebiased the EL84s in my JCA20H. The bias current is the same (within a couple of tenths of a milliamp) with the new Tung-Sols as it was with the Mullard Reissues. The amount of bass in the signal with the same knob settings is massively increased. Is this a normal thing? Have I just gotten used to power tubes that were wearing out, or could the new brand just sound that different?

 

[Boogie Bill]

Re: Power tube swap question

Yes, and yes. I've heard some major differences between 6L6 tubes from different manufacturers, so I don't find this surprising at all.

Enjoy!

Bill

 

[aleclee]

Re: Power tube swap question

What Bill said

 

[JeffB]

Re: Power tube swap question

The mullards have less lows. It's nothing massive, but there is a difference. Mullards are more midrange focused. If the are wearing out too , I suspect it could seem fairly dramatic