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Supratek Owners Thread

Greetings All - 
It appears that the 26-million-plus view, multi-decade "Preamp Deal of the Century" Supratek thread has been removed. I'm not sure why, but suppose there must be a reasonable explanation.
In any case, on that thread I recently asked whether there might be interest in a "Supratek owners thread" and received some interest. 
The purpose of this thread is for Supratek owners to share the details of their system, ask questions, share information about any tube-rolling they have done, and so forth.
I'll kick us off here with a few details about my system -
ancient Linn LP12 with Ittok arm, Dynavector 17D3 cartridge into Cortese LCR phono stage
Power amp is a fully serviced Innersound Electrostatic amplifier
Quad ESL63 speakers (not USA monitors) or JBL 4430 studio monitors
Digital sources are immature and evolving - ancient Fostex CR300 cd player/burner
DacMagic 100 DAC
Nordost Blue Heaven 75ohm interconnect
Due to the fairly long lengths of speaker wire required in the new listening room, speaker wire is Belden 12 gauge wire designed for low-voltage outdoor lighting systems. 
Next steps - dedicated circuit, new power cords, new interconnects, new wires.
128x128markusthenaimnut
isaacc7
44 posts
 
"Whats the benefit of doing the 12v?"

Just the cost really. The price difference between 6sn7 and 12sn7 can be dramatic especially considering that they are the same tubes other than the heater voltage. The data between 12j5 and 6j5 probably isn't as stark. I don't think Tungsol ever made round pate 6j5 tubes but Sylvania made their most sought after tubes in single triode versions. 

Oh, and I suppose I enjoy rescuing abandoned tubes lol. I get a kick out of using tubes that would otherwise languish. 
duramax747
207 posts
 
I'm a novice at best when it comes to tubes but I was under the impression that the 6J5 uses half the current/power as the 6sn7 hence why they last forever. 
In the Grange Signature Mick uses two 6J5 for each 6sn7.

Andy at Vintage Tube Service said the circa 1930 RCA 6J5GT are the ones to get.
jslateiv
64 posts
 
The 6J5 pulls half the heater current (.3ma) of a SN7 (.6ma)..   BUT, you have 2 of them per channel vs 1 sn7 so the total heater current draw is the same.  This does not effect the longevity of the tube provided it is being run at or close to the 6.3V spec.    In regards to the circuit and how the tube is driven/operated (ie, B+/bias),  it will be very similar as to how Mick runs the SN7 based pre's.   All in all,  they are all run very conservatively.    You'll find that any NOS tube stock (generally speaking),  especially that from the 60's and before to have very long life in Mick's pre amps,.. Tubes just aren't made like they used to be.   Newer Chinese manf. stuff,  not so much.  They can die (and do) with very few hours on them (comparatively speaking).
duramax747
207 posts
 
jslateiv,

I appreciate you taking the time to explain that to me. It makes sense. 

Do you use a Supratek?


jslateiv
64 posts
 
I do,..  Cortese LCR,  but am going to move to a Grange when Mick has time to make it.   Also have an older Chardonnay I picked up that I am currently refurbing to bring up to current spec/circuit.   It doesn't have a remote so will probably add that as well.  May keep, may sell once I'm done.  Not sure yet.   I handle most of the state side repairs for Mick to keep owners from having to ship all the way back to AU. My bench/services have been down the last 3 months due to a move but am back up and running now.    Generally speaking, his pre's are very solid and rarely need work.  He did have an issue recently with a bad batch of transformers that caused him a nightmare.  That has since been sorted out though.  I believe that there are a few users that posted here who unfortunately had some of those units (only about 6 in total,  a few made it to the US)..
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