C500T or C1000T MC phono tubes

Frank

Frank

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I want to change the internal tubes but only for the MC phono...not the MM but there is no indication inside ?
If someone has the answer...i thank him for it ;)

i already change all the phono stock tubes with Gold Lion but i want to change only the MC for Tesla ecc83 :rolleyes:

Frank
 
Good question Frank. I wondered myself. Hopefully we'll figure it out.
 
Argh...you are like my mentor in this hobby...so please don't put in my head this kink of idea :roflmao:
BTW, what do you think about your Audio Desk on new disk ?
 
Hi Frank,

Uh oh, don't follow me. :) I'll get you into trouble.

I confess that I have not used my TT yet. It is not set up. I was told that even new vinyl should be washed.

Frank said:
Argh...you are like my mentor in this hobby...so please don't put in my head this kink of idea :roflmao:
BTW, what do you think about your Audio Desk on new disk ?
Click to expand...
 
i found this, i was curious about the fact someone told me you could either run a mac pre tube or solid state and i was reading about them not too long ago. i know nothing about mac gear, so i could be wrong, but i think all 4 tubes are for the mm phonostage and then if you are using an mc cartridge the stepup transformer is solid state. which means you have to change all 4 tubes because the mc is the mm stage plus the step up which just adds gain to the mm phonostage.

this statement is where i got that idea from.
the C500 uses eight 12AX7 tubes: four in the high level circuit and four more in the phono preamplifier. The phono preamplifier circuit is all tube if you are using the moving magnet (MM) stage. If you have a lower-output moving-coil (MC) phono cartridge, the MC stage uses McIntosh’s own solid-state phono step-up modules instead of an input transformer. Four of the 12AX7’s are visible from the front panel, back lit in green, while the other four are beneath the top cover.
 
For both the C1000T & C500T, when you pop the top & look down the spine from the front, the front L&R are MC & the back pair are MM.

Inside the C500T and C1000T the MM tubes are designated with V1A and V1B whereas the MC phono is designated with a stenciling of V2A and V2B.

The phono stage schematics are the same for both pre-amps but the components are a little different.

If you are using MC only, use a cheap pair for the MM. Unfortunately, all the phono tubes burn even if those sources aren't selected.

I have TFK ECC803S in V2 & GL 12AX7 reissues in V1.

Both MM & MC phono stages are discrete circuits.

Front porch is line stage.
 
Steve said:
For both the C1000T & C500T, when you pop the top & look down the spine, the front L&R are MC & the back pair are MM. If you are using MC only, use a cheap pair for the MM. Unfortunately, all the phono tubes burn even if those sources aren't selected.

Both MM & MC phono stages are discrete circuits.
Click to expand...
oh sweet a mac guy finally showed up :) so that statement i pasted above i got from the mac website, what does that mean? it gives the impression that the phonostage is run by 4 tubes and its just stepped up with a ss step up for the mc. im confused.
but im sure you are right as im not a mac guy at all.
 
Great :congrats:

Thank you for both of you...Steve and Steve ;)

i will pass an order for a pair of tesla e83cc :wave: Or perhaps a quad...just in case ;)
 
There are SS Moving Coil step-up transformers in both the C500T & C1000T. (One for each channel). From there MC outputs to V2. MY understanding is that MM just uses the V1 tubes.

There seems to be some ambiguity but other owners of these pre-amps have also been rolling in their good tubes into V2 for the MC source.

The C1000P also has the MC step-up transformers. Reportedly, the P versions have a quieter MC phono stage being exclusively SS.
 
Tesla E83CC gold label, gold pin.
 

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Frank said:
Great :congrats:

Thank you for both of you...Steve and Steve ;)

i will pass an order for a pair of tesla e83cc :wave: Or perhaps a quad...just in case ;)
Click to expand...

Look forward to your findings. Get the gold label if you can. Military swords, even better but very hard to find. Be sure they are genuine small frame grid like below & not relabelled JJs or other fakes. Real Teslas do not have a round top like the JJs.

I use these tubes in the line stage (front porch). Awesome!

View attachment 6988
 
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Yes of course, NOS e83cc (white inscriptions) code 32 with yellow saber like i already have on the main front tubes of my c500t. But for me, impossible to find gold pin :(
i already sent a mail to tubemaze for a quote of a quad ;)

now i replaced my GL by a pair of Brimar 4004 just to test...not bad at all on Kind of blue of Miles Davis.
 
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