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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
rh67
307 posts
 
I own one of the 6SN7/DHT 300B/45 pre amps and it has to be one of the best sounding pre amps that i have owned without spending 25k and more.
alpha_lam
9 posts
 
I was referring to the b+ filtering cap for the DHT filament, which was soldered in reverse. This obviously would fail to work for its intended purpose of smoothing out ripple. I believe what my eyes see and you are just speculating that it was modded. These are the same electrolytic caps used for all filaments and the same as in the pictures of the supratek online. I bought this from a reputable dealer years ago.

Anyway it seems like negative comment is the minority here. 
rh67
307 posts
 
No, it's the fact what you posted is not the norm.

And what about your summary? What are you implying? Your experience with a used piece that was purchased ten years ago is what future new owners should expect to experience? The fact that what you bought was used and is not what most have experienced should make you think.
jslateiv
64 posts
 
@alpha_lam  The filament is run from a regulated DC circuit not B+,.  regardless,  there is a small electrolytic at the regulator output (5V assuming a 300b DHT) in PS box,..  if you are referring to a cap seen in the pre (not PS box) directly soldered to the socket pins this would not be an electrolytic cap and would not be for filament power filtering but would be a bypass cap.  As mentioned earlier there would be one on each filament pin.   Just trying to help you out here as what you are describing is not making a lot of sense from a circuit standpoint.  At least not how Mick builds his circuits..
alpha_lam
9 posts
 
Sorry I admit I'm not familiar with terminologies in tube circuitry. The problem I found was with the DC filament on the right channel. The DC wires from power supply are reversed. Here is a closer look https:/ibb.co/tKXVz4j
On the left channel is correct. Here is closer look for comparison. https://ibb.co/k17Zvdx
The electrolytic cap on the right channel swelled and fell off. I replaced them with Nichicon KG with the same ratings.

I am also disappointed to see power transformers used as output transformers. It is using the Talema 22VAC @ 0.8VA. It's hard to know the effect without some measurements. I might attempt to replace it as well.

I appreciate very much @jslateiv's constructive comment.
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