Most impact signal or power tubes?

[lschoonaert]

Hi guys,
I'm wondering what has the biggest impact sonically on a poweramp - the signal tubes or the power tubes? I have MC2301's and i just ordered some EAT diamond tubes to swap out the small signal tubes. Looking at the KT88 equivalent at EAT, it's really expensive to swap those 16 tubes - would it make much difference? Currently they're all McIntosh stock tubes.
Cheers, Luk

[vintage_tube]

Originally Posted by lschoonaert

Hi guys,
I'm wondering what has the biggest impact sonically on a poweramp - the signal tubes or the power tubes? I have MC2301's and i just ordered some EAT diamond tubes to swap out the small signal tubes. Looking at the KT88 equivalent at EAT, it's really expensive to swap those 16 tubes - would it make much difference? Currently they're all McIntosh stock tubes.
Cheers, Luk

Both IMO Luk -- if you become a subscriber for $25.00 USD, you can place an order for Gold Lion KT88 Reissues along with the Gold Lion 12AT7 Gold Pins and get a better deal than anywhere on the web.

The GL KT88's for members are $44.50 USD each and the 12AT7's are $28.75 USD each. $827.00USD for a complete MC2301 tube pair. Buyer reimburses exactly what I pay to ship overseas.

Not trying to downplay EAT's (Expensive Audio Tubes).

Best Sir,

Bob

[vintage_tube]

Advantages of becoming a member Luk -- I was going to private message you -- but you're not a subscriber -- so, can't.

https://www.audioaficionado.org/showthread.php?t=135

PayPal the $25USD for AA subscriber status. If no PayPal:

How to subscribe without a paypal account?

email Ivan at imesser@bellsouth.net & he can accept check, Visa or MC.


__________________


Best Sir,

Bob

[jdandy]

Luk.......The EAT tubes don't have the best reputation for longevity, particularly when you consider their price. I avoid them for that reason. The Gold Lion KT88 tubes are the way to go for your power tubes.

[vintage_tube]

Originally Posted by jdandy

Luk.......The EAT tubes don't have the best reputation for longevity, particularly when you consider their price. I avoid them for that reason. The Gold Lion KT88 tubes are the way to go for your power tubes.

Dan -- Didn't Neal (Beerdraft) have a complete set in his MC2301's years ago? He wasn't too thrilled w/them IIRC. Fuzzy memory.

Best Sir,

Bob

[jdandy]

Bob.......I believe you are correct. He had EAT tubes in his MC2301's and had several issues with them. He is not the only one. Many others have reported short lifespans with EAT tubes.

[lschoonaert]

Oh i was a subscriber - must have expired, i'll fix that - not for the special rates but just because i'd like to support this community that's always fun and helpful!

[vintage_tube]

Originally Posted by lschoonaert

Oh i was a subscriber - must have expired, i'll fix that - not for the special rates but just because i'd like to support this community that's always fun and helpful!

Cool Beans Luk. Welcome back to subscriber status.

Best Sir,

Bob

[mulveling]

Of course it depends on (etc, etc, etc), but I've done my fair share of tube rolling, and my general conclusions are:

• With rare exceptions, ALL tube positions make a significant difference, even in driver slots, follower slots, output slots, etc. Even sometimes in amps where people claim "tube rolling doesn't make much difference here because it's a grounded grid circuit" -- e.g. the EL34 tubes in my Blue Hawaii SE headphone amplifier.
• If a circuit is using a tube in a VERY bad way (e.g. running it beyond spec), then rolling that position can make even much MORE difference than usual, but it's not a good thing.
• Small signal tubes typically give you the best bang-for-buck in rolling opportunities, especially if you go NOS / vintage.
• Slots that "see" a lot of net downstream gain may need to be selected carefully for noise and microphonics. Some tubes/versions are have a reputation for microphonics in these sensitive slots (e.g. 6SN7GT, 12BH7).

[lschoonaert]

Mulveling, thanks for sharing your experience! Very insightful - i'm all new to tube rolling. Just been listening to my system for 2 years with stock tubes.