Different/same tubes for MM/MC phono stage?

[longgone]

Hi...

what do you think,
with regards to a C2300 preamp,
would you use the same tubes for the MM and the MC stages?

Currently using the MM stage.
Current tubes in MM stage are Telefunken 12AX7 17mm smooth plate.
I have more of the same tube.
I might be adding a second TT with an MC cartridge.

I have never had an MC cartridge TT.

Thank you for any response.

[MisterBritt]

Originally Posted by longgone

Hi...

what do you think,
with regards to a C2300 preamp,
would you use the same tubes for the MM and the MC stages?

Currently using the MM stage.
Current tubes in MM stage are Telefunken 12AX7 17mm smooth plate.
I have more of the same tube.
I might be adding a second TT with an MC cartridge.

I have never had an MC cartridge TT.

Thank you for any response.

I don't own that particular preamp. I have a 60th Anniversary C22, which I understand is very close to your preamp. Maybe I'm missing something. But on my unit, while you can select between MM and MC, the tubes in the "phono section" are the same tubes. I'm thinking your phono section, both MM and MC, uses the same pair of tubes in the circuit regardless of whether you select MM or MC at the faceplate.

[vintage_tube]

There are four 12AX7's for the phono stage in the C2300; two for MM and 2 for MC -- you can have 2 different types for each stage. Whatever you wish to do.

I had a wonderful C2300 and suggest trying the Gold Lion Gold Pin 12AX7's from Russia (12AX7GENGP/ECC83/B759). They are wonderful 12AX7's and IMO wipe the floor of any other tube available -- whether new or old.

Best sir,

Bob

[longgone]

MisterBritt, thank you.
I believe the C2300 has a pair of tubes for MM stage and a pair of tubes for MC stage.

[jdandy]

Originally Posted by longgone

MisterBritt, thank you.
I believe the C2300 has a pair of tubes for MM stage and a pair of tubes for MC stage.

Don.......You and Bob are correct. The C2300 uses separate pairs of 12AX7 tubes for their phono stages. The Telefunken smooth plates are excellent tubes. I use a pair of Telefunken ECC83 / 12AX7 tubes in my C2300 moving coil phono stage. I find the Telefunken tubes to be very quiet when compared to other tubes. They have a wonderful sound but their low noise in the amplification stage of the low output moving coil phono stage is what is most impressive to me, and why I use them. In your moving magnet phono stage the voltage levels are considerably higher which tends to mask the noise floor in tubes that are not as quiet as the Telefunken tubes. I suggest you try a pair of Gold Lion ECC83/B759/12AX7 gold pin tubes in your moving magnet phono stage and use the Telefunken's in the moving coil phono stage.

[MisterBritt]

Originally Posted by longgone

MisterBritt, thank you.
I believe the C2300 has a pair of tubes for MM stage and a pair of tubes for MC stage.

Roger that. I'll watch this this thread and learn. Thanks.

[longgone]

vintage tube, thank you.
I think I bought my Gold Lions from you when I first got my C2300.
They are fine. I was in somewhat of a tube frenzy back then and I settled on the Telefunken 17mm smooth plates. It might be time to revisit the Gold Lions?
Probably a good idea to have the same tubes for both stages?
But not necessary.
Understood.

[longgone]

Thanks Dan and all for sharing.
Dan, your suggestion sounds good.
I've not had an MC cartridge, yet.

[jdandy]

Britt.......The McIntosh C22 Anniversary preamplifier uses the same tube compliment as the C2300. The tube compliment listed below is direct from the C22 Anniversary Owner's Manual.

High Level Circuitry: 2 - 12AX7A
MM Phono Circuitry: 2 - 12AX7A
MC Phono Circuitry: 2 - 12AX7A

[MisterBritt]

Originally Posted by jdandy

Britt.......The McIntosh C22 Anniversary preamplifier uses the same tube compliment as the C2300. The tube compliment listed below is direct from the C22 Anniversary Owner's Manual.

High Level Circuitry: 2 - 12AX7A
MM Phono Circuitry: 2 - 12AX7A
MC Phono Circuitry: 2 - 12AX7A

I'm not sure if I'm following. Let me start here. Let's say you have the top off the unit and you're looking down at the tubes from the front of the unit, as if you were about to turn it on. There are six tubes. My understanding is the first two tubes to your left are the phono section. The middle two tubes are the D/A. And the two tubes to your right are the CD. Correct?

I'm on the McIntosh website and have the owners manual open in front of me on another screen. I see on page 14 what you supplied, but I don't see where it indicates which tubes are which.