Wish Power tube changes pull relevant parameters with the tube type


It seems like you haven't read this :)
https://forum.fractalaudio.com/threads/no-differences-when-changing-tubes.163545/post-1962569

Yes, you can only use the transconductance values when changing between tubes with roughly the same maximum power dissipation. It doesn't work if you want to change a 6L6 to an EL84.

I know everyone wants this to work like a real amp but it's simply not going to happen. Some amps let you swap between EL34s and 6L6s and change bias accordingly. The problem is the Axe-Fx III lets you change between all the possible tube types. If you were to put an EL84 into an amp designed for EL34s it would sound terrible (and also destroy the EL84). A pair of EL84s wants to see upwards of 8K plate-to-plate. A pair of EL34s wants to see around 3.2K. If you put the EL84s in the amp the transformer would be extremely undermatched. It would also exceed the SOA of the tube and destroy it. In the Axe-Fx III the virtual tube wouldn't be destroyed but it would sound terrible and people would complain it doesn't sound right.

Those amps where you can use different power tubes don't swap the transformer. They just rebias the tubes. If the transformer turns ratio is optimized for 6L6s installing EL34s will cause the transformer to be slightly undermatched which is the primary reason the tone changes. Conversely if the transformer is optimized for EL34s installing 6L6s will cause it to be overmatched.

You have far more control over the power tube response with the Axe-Fx. Rather than complaining that swapping power tubes doesn't work exactly the same learn to use the fantastic power available to you. Learn to hear the difference changing the Transformer Matching and/or Speaker Impedance makes. These are controls you'll never find on a real amp. Changing the matching on a real amp involves removing the transformer and installing a new one. If you want fine gradation in matching you'd need something with many taps.

Frankly all this compalining about something you have far more control over sounds entitled and whiny.
 

If you're talking to me, yes, I have read it. And my wish was posted prior to Cliff's posting, IIRC.

Cliff said, "If you were to put an EL84 into an amp designed for EL34s it would sound terrible (and also destroy the EL84)." My point is that I, at least, wouldn't complain about that. Particularly if, as suggested elsewhere, there was a switch you could throw that would toggle between normalized and authentic. But even without that, I don't find myself typically swapping EL34s out for EL84s. I find myself wanting to try EL34s or KT88s in my ODS amp, just as I have in the real world.

If Cliff is saying it's not going to happen because it is too difficult, or it can't be done or something, fine. I'll settle for recommended values changes. But I don't understand people jumping on board to poo-poo a reasonable idea in the wish list. Particularly one that seems to have some traction.
 
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