Balanced Triodes?

[Trotter]

Is it always important that the 12AX7 closest to the power tubes has balanced triodes?

I'm getting ready to re-tube a couple amps (JCM900 and Hiwatt DR504).

Thanks!

[Blue Strat]

It's never important for that socket unless, through trial and error, you've found that using one sounds better to you.

The only socket where balanced triodes could be a benefit is the phase inverter socket, the one closest to the power tubes.

Let the debate begin! :)

[aleclee]

The only socket where balanced triodes could be a benefit is the phase inverter socket, the one closest to the power tubes.

Let the debate begin! :)As Mike's comment indicates, there's some debate about the benefit of balanced PIs. Some folks swear by 'em, others think it doesn't matter while another group prefers unbalanced PIs.

As with most things regarding tone, YMMV since it's really just a matter of taste.

[Trotter]

When looking for tubes for my Vox AC15CC, Eddie at Eurotubes recommended that the 12AX7 in V2 (FARTHEST from the input jack, not closest) was the one you wanted balanced.

sorry, in my original post I meant to say 'closest to the power tubes'... not the input jack... still haven't had my coffee this AM!

[Blue Strat]

Hey Trotter, just realized that you're in Anchorage. Do you know Jerry Bever? He hangs out here and is also in Anchorage.

[jbever]

Mike and Paul, allow me to do the introductions. Mike, yes Paul and I know each other. He and I have gotten together several times to play each other's gear. Paul's got some great vintage and collector stuff. Paul's a great guy.

Paul, let me introduce Mike. Mike owns KCA NOS Tubes in Virginia. I get all my tubes from Mike. Tell what amp you got, what your budget is and he'll fix you up with the best you can get. Mike actually came to Anchorage for a vacation a while back and I got to by him dinner! I never thought a man could eat 20 lbs. of crab in one sitting! Mike's got a great website with good info. One good thing to do is go his profile and read over his past posts, there's a wealth of good discussions there! Mike, you should publish a book of nothing but those conversations!

Play nice and talk to you both later. Paul I saw you have a crunchbox, I might have to hear that thing, they say it's great.
Jerry

[Trotter]

Mike and Paul, allow me to do the introductions. Mike, yes Paul and I know each other. He and I have gotten together several times to play each other's gear. Paul's got some great vintage and collector stuff. Paul's a great guy.

Paul, let me introduce Mike. Mike owns KCA NOS Tubes in Virginia. I get all my tubes from Mike. Tell what amp you got, what your budget is and he'll fix you up with the best you can get. Mike actually came to Anchorage for a vacation a while back and I got to by him dinner! I never thought a man could eat 20 lbs. of crab in one sitting! Mike's got a great website with good info. One good thing to do is go his profile and read over his past posts, there's a wealth of good discussions there! Mike, you should publish a book of nothing but those conversations!

Play nice and talk to you both later. Paul I saw you have a crunchbox, I might have to hear that thing, they say it's great.
Jerry

Hi Jerry. Yep, I've bought from Mike before and the knowledge and service were top notch! He got me all setup with new tubes for my old Mesa Mark III... (excellent recommendations by the way; SED's and Tung-Sols).

Give me a ring or shoot me an email, you can borrow my Crunchbox pedal anytime you want.

[Blue Strat]

Hey Jerry! Thanks again for the dinner! I'm "Jonesing" for S&S, Phylis' (crab melt sandwich), and Humpys (best fish and chips ANYWHERE!).

Can't wait to get back to Anchorage!!!!

[VaughnC]

Is it always important that the 12AX7 closest to the power tubes has balanced triodes?

I'm getting ready to re-tube a couple amps (JCM900 and Hiwatt DR504).

Thanks!

Sounds like you're talking about the phase inverter tube. Rarely are phase inverter circuits themselves (the components around the tube itself) actually balanced. So, a balanced triode could actually throw a phase inverter circuit out of balance :jo. My best advice would be to let your ears be the final judge.

[Blue Strat]

Wouldn't a balanced tube maintain the "out of balance" condition in an out of balance circuit? ;)

An out of balance tube could balance an out of balance circuit, or vice versa....but which sounds better? There is no answer.

The only thing conclusive about a balanced PI tube is that if you always use them, the resulting balance of the PI circuit will be consistent.

[rockon1]

Wouldn't a balanced tube maintain the "out of balance" condition in an out of balance circuit? ;)

An out of balance tube could balance an out of balance circuit, or vice versa....but which sounds better? There is no answer.

The only thing conclusive about a balanced PI tube is that if you always use them, the resulting balance of the PI circuit will be consistent.

That sums it up nicely Mike. Still for me its -balanced shmalanced! Ive got too many cool unmeasured tubes not to try out! :) Bob

[VikingAmps]

Sounds like you're talking about the phase inverter tube. Rarely are phase inverter circuits themselves (the components around the tube itself) actually balanced. So, a balanced triode could actually throw a phase inverter circuit out of balance :jo. My best advice would be to let your ears be the final judge.

Most phase inverter circuits I've seen are pretty well balanced by design. Usually within 5% with a balanced tube.

[donnyjaguar]

Agreed with Redman. The NFB circuit will take care of any variance anyway. The discussion is moot.

[Blue Strat]

Does NFB remove the DC offset? That's what we're referring to when we talk about balanced triodes.

[mark norwine]

Still for me its -balanced shmalanced!

I'm from that school, too.

Was "Band of Gypsys" recorded with "ballanced triodes"?

Allmans at the Filmore?

Pet Sounds?

My guess would be "no"

[mark norwine]

Does NFB remove the DC offset? .

No.

[Blue Strat]

I'm from that school, too.

Was "Band of Gypsys" recorded with "ballanced triodes"?

Allmans at the Filmore?

Pet Sounds?

My guess would be "no"

My guess would be....no one knows. Hence what's the correct answer?

There is none.

[Blue Strat]

No.

That was a rhetorical question;)

[mark norwine]

If a tree falls in the forrest.....:D

[mark norwine]

Hey....what's the latest on you coming to NJ next month? I may have a scheduling conflict, but if you're coming, I'll get out of it...

[Blue Strat]

Hey....what's the latest on you coming to NJ next month? I may have a scheduling conflict, but if you're coming, I'll get out of it...

I don't think I'm going to be able to make it, so jump on your other plans.

[mark norwine]

my "other plans" pale in contrast, so if you change your mind, please give me a shout...

[jbever]

If a tree falls in the forrest.....:D


... and nobody hears it ... can we make an amp cabinet out of it!!

[Blue Strat]

... and nobody hears it ... can we make an amp cabinet out of it!!

only if it's exotic wood:)

[VikingAmps]

Agreed with Redman. The NFB circuit will take care of any variance anyway. The discussion is moot.

Even without NFB.