Which Tube for the Phase Inverter?
- Thread starter Marcel
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KLINKDETROIT
New member
Re: Which Tube for the Phase Inverter?
Eh12ax7 110/110
Eh12ax7 110/110
marvar
New member
Re: Which Tube for the Phase Inverter?
The brand of tube you use isn't as important as the PI is not really part of the tone shaping stage- it's more important that they are pretty closely balanced or matched- yes it can some effect on your tone- but only as to how much gain they deliver to the power tubes.
The brand of tube you use isn't as important as the PI is not really part of the tone shaping stage- it's more important that they are pretty closely balanced or matched- yes it can some effect on your tone- but only as to how much gain they deliver to the power tubes.
kmcguitars
GuitarArtologist
Re: Which Tube for the Phase Inverter?
I don't mean to throw gas on the fire.
But I really don't buy into the Matched PI tube idea. This makes sense to me in the HiFi Audiophile world.But I've never viewed my Guitar amp as a HiFi circuit. ( That is THD less than 0.05%) I could be wrong? But I think Guitar amps are the only circuits that still use carbon composite resistors or at least I prefer them in my amps. If you can hear a tonal difference with a matching PI tube,by all means go for it.:smokin:
I don't mean to throw gas on the fire.
But I really don't buy into the Matched PI tube idea. This makes sense to me in the HiFi Audiophile world.But I've never viewed my Guitar amp as a HiFi circuit. ( That is THD less than 0.05%) I could be wrong? But I think Guitar amps are the only circuits that still use carbon composite resistors or at least I prefer them in my amps. If you can hear a tonal difference with a matching PI tube,by all means go for it.:smokin:
marvar
New member
Re: Which Tube for the Phase Inverter?
There is a never ending discussion as to whether the PI should be balanced or not-some prefer the sound of an unbalanced- some don't- personally I prefer the balanced. there is a good discussion about this at Myles Rose's website- he is a noted tube guru, and yes he does work for GT as well as himself, but in all his discussions he is pretty careful not to be biased in GT's favor- anyway, check it out for yourself and make your conclusions. THe part about matching PI starts about half way down the page.
http://www.guitaramplifierblueprinting.com/GTlink.html
There is a never ending discussion as to whether the PI should be balanced or not-some prefer the sound of an unbalanced- some don't- personally I prefer the balanced. there is a good discussion about this at Myles Rose's website- he is a noted tube guru, and yes he does work for GT as well as himself, but in all his discussions he is pretty careful not to be biased in GT's favor- anyway, check it out for yourself and make your conclusions. THe part about matching PI starts about half way down the page.
http://www.guitaramplifierblueprinting.com/GTlink.html
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aleclee
Major General GAS
Re: Which Tube for the Phase Inverter?
Count me as another who doesn't buy into the matched PI argument. First off, how matched is matched? Secondly, how matched are the components around the PI? If they're not perfectly matched, a perfectly matched PI tube will only reflect the amp's inherent imbalance. Remember that many amps are built with 20% components--that variance is probably greater than all but the most unbalanced dual triodes. Finally, a number of people find the assymetric waveform of an unbalanced PI to be preferable that produced by a balanced PI.
I'm happy to spend money where I think it'll yield better tone but when it comes to balanced PIs I'm in no hurry to open my wallet.
Actually, in a lot of Marshalls and similar amps, the PI is where much of the crunch is created.marvar said:
Count me as another who doesn't buy into the matched PI argument. First off, how matched is matched? Secondly, how matched are the components around the PI? If they're not perfectly matched, a perfectly matched PI tube will only reflect the amp's inherent imbalance. Remember that many amps are built with 20% components--that variance is probably greater than all but the most unbalanced dual triodes. Finally, a number of people find the assymetric waveform of an unbalanced PI to be preferable that produced by a balanced PI.
I'm happy to spend money where I think it'll yield better tone but when it comes to balanced PIs I'm in no hurry to open my wallet.
aleclee
Major General GAS
Re: Which Tube for the Phase Inverter?
:bsflag:He might not blatently push GT stuff on his web site but from what I've seen, 100% of his posts on discussion boards are oriented towards promoting GT or other companies with which he has a business relationship. I have no doubt that he knows his stuff but he has a PT Barnum streak a mile wide.marvar said:
Gearjoneser
Gear Ho
Re: Which Tube for the Phase Inverter?
I've never paid any extra for a balanced pre tube. I just make sure they're high quality and new, and normally use something like a JJ ECC83S, like Scott mentioned. I love JJ power tubes, but I tend to only use JJ pre tubes as PI's or reverb drivers, or FX loop drivers. When it comes to the 1st and 2nd gain stages, it's gotta be a GT-C, Mullard, Telefunken, Tungsol, or Sovtek LPS.
I've never paid any extra for a balanced pre tube. I just make sure they're high quality and new, and normally use something like a JJ ECC83S, like Scott mentioned. I love JJ power tubes, but I tend to only use JJ pre tubes as PI's or reverb drivers, or FX loop drivers. When it comes to the 1st and 2nd gain stages, it's gotta be a GT-C, Mullard, Telefunken, Tungsol, or Sovtek LPS.
aleclee
Major General GAS
Re: Which Tube for the Phase Inverter?
Seriously, if it sounds better to you, that's great. What's voodoo to some is magic to others.
I agree. You go bug-eyed from looking so hard to tell the difference. :laugh2: Personally, I'd rather waste, uh, spend my money on oxygen free cables than balanced PIs.Marcel said:
Seriously, if it sounds better to you, that's great. What's voodoo to some is magic to others.
marvar
New member
Re: Which Tube for the Phase Inverter?
As I said before- each has it's own merits- but I can defineatly hear a difference in my Marshall using a matched PI vs a regular 12ax7- and I have alot of them I have tried out in that position- from Phillips NOS, Boogie- Sovtek, RCA NOS, et,al- and I keep going back to the balanced GT 12ax7M.
It sure won't hurt your amp to have a balanced PI-and really guys- 5.00 -$10.00 extra isn't alot to spend on your amp anyway. Heck, you probably spend that much on sodas/coffee in one day.
As I said before- each has it's own merits- but I can defineatly hear a difference in my Marshall using a matched PI vs a regular 12ax7- and I have alot of them I have tried out in that position- from Phillips NOS, Boogie- Sovtek, RCA NOS, et,al- and I keep going back to the balanced GT 12ax7M.
It sure won't hurt your amp to have a balanced PI-and really guys- 5.00 -$10.00 extra isn't alot to spend on your amp anyway. Heck, you probably spend that much on sodas/coffee in one day.
greendy123
New member
Re: Which Tube for the Phase Inverter?
I was wondering about the tone on the phase inverters, does it matter at all because its doesn't contribute to the tone as much as the pre-amp tubes used to create the distortion. Putting reliability aside does it have a big effect.
I was wondering about the tone on the phase inverters, does it matter at all because its doesn't contribute to the tone as much as the pre-amp tubes used to create the distortion. Putting reliability aside does it have a big effect.