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.

Mick just sent me this link to his latest blog post, featuring the Grange with a picture of mine on top (Reimar's White Grange): enjoy the read from the pen of the man himself!


Glad to hear this @rrboogie . Horns are very demanding. Adjustable gain is a Supratek advantage. It allows better system matching and lower noise.

Those are some highly rated linestages. Glad it is performing so well. I considered Modwright and Rogue before ordering a Supratek. I think 6SN7 tubes and avoiding circuit boards is a step in the right direction. 

Thanks for the review,


depending upon the 300b tubes you have installed maybe,  maybe not..   you need to measure.  the dimensions of the GF tube are given at the site.   

Great thread!

I am pondering Supratek Cortese LCR preamp. Currently have EAR Yoshino 868PL which is also a full function preamp and is currently paired with Pass Labs XA30.8 amp.

Just wondering if anyone compared EAR preamps with Supratek? The EAR preamp is very good, absolutely nothing wrong with its pairing with Pass Labs but I am looking to get MORE air, bloom and realism in the music.

If it's "bloom" you want, Mick's creations are hard to beat. Any music passing through my Grange sounds just "grand" and very intoxicating (same preamp-stage as the Cortese). For two months now I have burned the night oil with this extraordinary instrument with all musical genres and analog as well as digital sources. In my opinion, a Supratek preamp is a final purchase.


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Anyone take delivery of a Supratek recently?  

Originally ordered a dark brown wood/chrome Chardonnay and ended up upgrading to a Cabernet 6SN7 since Mick had one available to ship sooner.  Might have been a cancellation…don’t know.  Mick mentioned he was having a very difficult time getting new tubes and said he was sending quality NOS tubes from his stash.  I received Radiotron (RCA Australia made 50’s-60’s) 6SN7’s, Russian made 6N3C’s 90’s?, Russian 5U4C 90’s for my set of tubes.  Curious to hear what tube set any of you received?
Also, would like to hear from any Cab 6SN7 owners on what tubes you are using or prefer.  Thanks



The Russian military tubes are pretty standard for him when he can get them but the NOS Radiotron's are an upgrade from the normal.  The 6SN7's should be fine as are the the Russian 6L6's.  I would look for a NOS rectifier though as the first swap.  They are getting more and more expensive but a good one should last you many years. 

@jackd Thanks for the input.  What tubes are you using?  Nice to hear what others are doing. I have a selection of NOS 6l6’s and 6sn7’s that I can play around with.  What rectifier do you like or recommend? I have some 5u4g’s are they compatible 5ar4 sub?  Much appreciated.



I have both a Chardonnay and a Cabernet in two different systems and use Blackburn Mullard 5AR4's in both mainly due to the slow start-up feature.  Have used all of the other compatible 5 volt variables but always end up back with the 5AR4's.  As I leave my SS amps on all the time I don't get the noise at start-up and especially turn off with the 5AR4's I get with the other variants.  My next favorite of the rectifiers are the RCA 5AS4's a 5U4 variant.  In both preamps I am using the 6L6 tubes Mick supplied as I tried other modern ones and didn't hear a difference.  Never had a reason to own NOS samples.  Am using RCA 6SN7 GT's currently in both units but in the past have had good luck with Hytron 6SN7 GT's and Raytheon VT-231's. I own several NOS pair but never saw or heard the fascination with 5692's. I own two pair of 1943 Sylvania GT's that I bought NIB almost 25 years ago that on occasion I will put in one pair in one of them just to see if they can stay put but it hasn't happened yet. After almost four years of rolling 6SN7's in the two preamps I'm kind of settled in for a while with what's in them. 

@tksteingraber I have put many tubes through my Cabernet. Keep in mind that sounds good will vary depending on what tubes I have in mt amp. When Mick built mine I had him put in a 6v/12v switch. Best thing I ever did. 12sn7 are much less expensive4. 

Favorite 6sn7(ish) tubes in no particular order:

Raytheon 6f8g T plates

Sylvania tall plate 14n7. They aren’t the same as the 7n7!

GEC/Osram/Marconi b36

Ken Rad round plate 6f8g

Interestingly, to me at least, is that I haven’t really liked having the Sylvania so called bad boys or Tungsol black glass, round plate in my Cabernet. And, yes, they are actual bad boys with the right dates, construction etc. I do like the Tungsol BGRP as drivers in my push pull amp. 


I have also had a lot of luck with single triodes with the use of adapters. Mick makes his Grange with 6j5. The 6/12j5 and equivalents, while rising in price quickly, are still good deals compared to the 6sn7 market. Here are some of my favorites:

Radiotron (from Australia) 6j5gt

Raytheon 12j5wgt

National Union JAN 12j5gt

Cossor branded 6c5g. There’s some debate who actually made these but they aren’t the GEC. Currently available from Langrex.

GEC l63gt brown base. 

Fun fact, the 6c5 is a good substitute for the 6j5 and I got Mick’s blessing to use them in the Cabernet. The 6c5 is actually, literally, a 6j7 triode wired so it is possible to use that configuration with the appropriate adapters as well. Haven’t done that yet but I will soon. 

@isaacc7 Thank you for your helpful tube expertise.  I am not familiar with many of these tube types.  Which types would be direct drop in’s for the 6v cabernet without using adapters?  Much appreciated!

Heh, just realized all of the ones I mentioned need adapters lol. These should be pretty close to the same tubes if you get the 6sn7 versions but the prices will make you cry:)


GEC/Marconi/Osram b63

Raytheon VT231

Sylvania 6sn7wgt 

I’m not sure if there is an equivalent 6sn7 to the round plate Ken Rad… My advice is don’t be afraid of adapters, especially if you want access to the best sounding tubes at a reasonable cost. 10-15 years ago you could buy any tube you wanted even if some were more expensive than others. Now some of the best tubes are difficult to find and are incredibly expensive when you do find them. I think the NOS tube rolling game has just about run its course, at least for the generally accepted “best” versions. You can still get great single triodes. A 6j5 is just a half of a 6sn7 so two of them are exactly the same electrically. Mick would be happy to make a preamp with 2x 6j5 instead of 6sn7 if you don’t want to use adapters. Or do what I did and get the option to use 12v tubes *and* use adapters:)

@isaacc7 Oh well I think I will start out with traditional 6sn7 tubes.  I really don’t want to mess around with adapters starting out.  Mick included a 40-50’s Radiotron 6SN7gt pair made in Australia.  I have pairs of Rca grey glass 6SN7gt’s, Rca 6SN7gta’s and Raytheon 6SN7gtb’s from the 50’ s to start out. Power tubes I have a selection of 6L6’s to try as well.  Should be fun.  Thanks for your suggestions.

Regarding the use of adapters - In the owners manual Mick cautions against "excessive" tube rolling, because it can cause the sockets to eventually lose some of their grip.

Hence I use socket savers.

In my DHT i'm using Cossor WE300b tubes which are a major upgrade over the stock Psvane tubes. For a rectifier tube i'm using a Phillips 5R4GYS immediate improvement over the JJ GZ34, the music is cleaner with an added layer of textures presenting a very real soundstage. The 6SN7's have made the least impact as to sound maybe because of their use as driver tubes, i'm using original Bad Boy's. The Cossor WE300b's are very close in sound to original WE 300b's and for the price are hard to beat i bought mine from VKmusic. The biggest surprise was the 5R4GYS rectifier tube which was a major improvement in sound right from the beginning.

Thanks everybody on this thread for sharing your experience with Supratek/Mick. It was extremely useful to me making my decision.

I just placed an order for Cortese LCR preamp/phono.

I cant wait to receive and hear this preamp. It was go against my current pre - EAR Yoshino 868PL preamp so stakes are somewhat high already.

I will share my few months once I receive it..


Finally set up my Cabernet 6SN7 on my main system. I am using an LSA Warp 1 class D amp while I wait for my Decware Torri to be built in a few months. Sounds fantastic. I did order a Revelation Audio Labs umbilical cord and ii is a nice addition to Mick’s stock cord. First impression of the cords prior to full break-in is Mick’s sound more warm with larger soundstage like tubes and Rev Audio’s sounds bright/ detailed more like solid state. Any input on how these cords settle in?

It’s been interesting working with Mick he’s a great guy. Ordered a Chardonnay but he was having transformer parts delay so he offered a Cab at a discount instead to avoid an extended delay. Then he was also having difficulty getting tubes so he sub’d some 40-50’s Aussie 6SN7’s. One tested low on arrival and failed badly the second time I used it. The chassis serial number labels had Chardonnay listed as the model and I had to ask Mick to send me new labels which he forgot about until I asked a second time. None of these are a problem for me I understand all the supply chain issues and he is quite busy dealing with it all. He is an accommodating guy of his word and aims to please. One last etiquette question…should I ask Mick for replacement 6SN7 tubes? He didn’t offer when I told him the tube failed? I wasn’t going to ask and just chalk it up as bad luck but wondered how others would respond. Thanks

Honestly @tksteingraber  I wouldn't worry about asking Mick to send replacement sn7's.   Your better off finding some good ole NOS USA (or new/current) ones from a reputable local (US) source and going that route.  Things take such a beating these days during travel and it's a long trip from AU.   A decent pair will cost you about the same as his shipping cost to you..

@jslateiv Thanks…yes I have a few 6SN7 pairs of old stock ‘50’s-60’s RCA’s and Raytheon’s that sound very good and test strong.  Mick’s Russian tubes don’t seem to be up to the task for the Cab. Sounded slightly grainy not as clear.  I rolled some of my tubes yesterday and noticed my tubes were better across the board.  I settled in with GE 5AR4 ‘60’s copper plates, RCA 6SN7GT ‘50’s gray glass, and Shuguang ‘70’s mlitary 6L6 coke bottle. Really enjoy the SQ as it all breaks in👍.

Ok after a few days of tweaking and tube rolling with my Cabernet I have discovered fuses and tubes make a significant difference in SQ. I installed a QSA Yellow fuse and wow it made a significant SQ improvement.  Tubes have made a difference and I am now using RCA 6L6GC ‘60 black plate bottom getter, RCA 6Sn7 GTA  black plates and a 5AS4A rectifier.  Wow nice SQ!


Little update on my Cortese LCR order that I had placed with Mick a while back.

I decided to upgrade my order to the Signature Grange.

Can’t wait to receive it from Mick.

Hope I have done the right thing and hope the 16 tubes won't heat up my room!


Somehow your post about upgrading your order to the Signature Grange... well, it really got me thinking. That might be a really nice next step from my Cortese LCR.

Supratek chrome model owners: I thought I would share that I came across some nice chrome domed tall guitar volume/balance knobs that look great on the preamps. I didn’t really care for the matte aluminum stock knobs. The only downside ,which is of no concern for me, is they don’t have a level mark on the knob.

Amazon link:

Picture (if it works) of the knob comparison:


Well, I finally received my Signature Grange preamp after about 6 month long wait.

I initially had ordered the Cortese LCR but later upgraded my order to Signature Grange.

Mick has been wonderful to deal with.

Currently the Supratek preamp is mated with Pass Labs XA30.8 and running stock tubes provided by Mick.

The preamp has exceeded my expectations. It is one hell of a preamp. My previous preamp was EAR Yoshino 868PL, which is a great preamp as well.

Comparing both the preamps, the Grange has more body and dynamics, tonally more rich and overall more musical. Bass is more well defined as well.

The Grange looks like a fine instrument. It is the ONLY audio component that my wife complimented on...which says a lot. LOL

Thanks to everyone on this thread for providing feedback on Supratek and Mick.

Very nice to hear another  happy Supratek owner.  Its the best stereo system decision I have made.  I am blown away how good my speakers sound.  I had no idea they had it in them.  🤣 My wife walked by my chrome Cabernet and said “That is a really beautiful component”. First and only complement I have heard from her in regards to my stereo systems. 👍

For my Cab the tubes and fuse make a huge difference.  Especially the rectifier and 6SN7’s. Output tubes not so much.  Enjoy the music!

@tksteingraber, took delivery of Cabernet mid Nov 2023.

The tubes that are fitted:

6SN7-SE (2)

6N3C (0384) (2)  the 'N" looks like a russian n

GZ345 Rectifier (1)

The sound is a bit rough out of the box, letting it burn in from today for a week, see how that works out. By then, that should be 250 hours, is that enough?


They do take a little time to settle in when new.   You'll notice a nice difference within a couple days (20-30hrs),.  Those Output transformers need a little juice running through them to open up.. The supra's also like to be at stable operating temp to sound their best too (~45 min. on)..  A little congested before that point.   The 6n3c is the Russian eq. of a 6L6..  I personally like the 5ar4 (gz34) and 5u4gb rectifiers but you'll find a big difference of opinion on what people like.  If yours cab is a 6sn7 standard (ie, no DHT),  then your rectifier choices are pretty wide open..  just stick with the typical 5volt heater variety,.

@jslateiv question for you on my 6 month old Cab volume control.  Whenever I use the remote volume up or down I get a crackling  sound. If I turn the volume knob up and down a few times it goes away but returns next time it’s turned on.  Should this be of concern?  Thanks for your expertise.  


@rms456 excellent to hear about your new arrival🤣. Once it breaks in and if you have an interest in upgrading your tubes I have several suggestions that made a definite improvement. I have rolled many 6sn7’s, 6f8g’s , 6l6’s as well as 5V rectifiers. Also, highly recommend upgrading your fuse to a Swiss Fuse Box. All nice SQ enhancements. Cheers!

@tksteingraber   You will hear a little crackling when the remote is used due to the motor interacting with the high gain circuit.  You should only hear it while the motor is turning the vol up or down (remote) though.  Should stop once you take your finger off that remote button.    Sometimes if you have a cell phone near (~3') of the pre,  the pre will pickup some rf from the phone and you could hear some cadenced ticking and or a little static in the background.    IF you hear/get the crackling from the volume when manually engaging the control at the unit, I would suspect a dirty pot,  but these are sealed so not much you could do about it other than replace.   If it's silent other than when turning up/down manually,  I would worry with it. Won't harm anything.

@jslateiv many thanks for the excellent explanation.  All good…the Cab only makes noise using the remote.

@jslateiv , there is a difference now on the burning in process, now 48 hours in. An FM Tuner (Yamaha TD-500) is feeding the input and monitoring with SPL headphone amp, HD820. Power is raw house AC power, no special cabling on AC lines at all. Interconnects are Accuphase ASL-10B, AL-10 well used.

If the source is ordinary and it sounds 'better' as time goes on, that roughness out of the box is slowly disappearing.

What I mean by rough, is dropping sound stage height and missing the stage between centre and left and right, falls in a hole there as encountered in the main system. The effect on an equivalent digital only level, is closely the same as the change in USB cables. Guessing that common mode noise is an issue there. Bass is lost in the early hours, but is coming back. 

The manual that came with the Cabernet advised the GZ345 was good only for 2000 hours. Could you recommend another tube with longer life and an SQ a bonus?


I have found that a good 50hrs seems to open up the OPT's,..  I always hear a difference in the first hour as the unit gets hot and temps stabilize.   Tubes can be hit or miss with their own break in,..   some don't require much time and some do,..  doesn't really matter the brand, age, etc..  this is more specifically to the output tubes,  not rectifier or regulator tubes..   If you hear the center or imaging shifting back and forth some,  thats the tubes..   They generally always settle in at some point.  I have had some that were stable for the first few hundred hours and then shift only to restabilize and lock into place.  Kinda crazy but nature of the beast if you will..   GZ34 (5AR4) should last many thousands of hours,..  5k at least if not 10,..   the power supply on your unit is pretty easy on them,.  The dht cabs pull a bit more current but a straight SN7 cabernet is a pretty light load. 

@rms456 not sure what rectifier make came stock but I would suggest you try a few different rectifiers. They do sound different and can enhance the SQ and last many years. My list that I have used on my system in order of my preference.

Sylvania US Navy 5U4GB Straight tall bottle, square top getter= just sounds best in all ways

RCA 5R4GY ‘58 Brown base ST bottle = Detailed full warm sound that just fills the space more

RCA 5AS4A ST bottle = Detailed full warm sound

Mullard GZ34 ‘66 = Excellent clarity and detail but lacked the full warmer sound others have. Narrower sound stage. More like studio recording vs symphony hall recording

Sovtek ‘90’s 5AR4 = very nice all around just not as good as the rest. Could live with it.

GE 5AR4 ‘60’s copper plates = similar to Sovtek with less punch and detail.

Russian Stock Supratek Rectifier = same as GE just less of it.

Cheers and enjoy!

@tksteingraber , the shipped rectifier tube with the Cabernet 6SN7 is from JJ Electronic (Slovenia) JJ GZ34 5AR4 is their ID.

Many thanks for the list of choices...looks like the RCA are a good start.

I tried Ingress rollerblocks under my Grange and heard some nice sonic improvements. 

From what I understand they are similar to Symposium rollerblocks but at a fraction of the price. I might try them also under the Supra power supply unit.

There are few forums mentioning the Ingress products as well.


Anyone have Supratek amplifier? I'm so happy with my Supra preamp that I am thinking of a Supratek 300B or EL34 amp. Any feedback would be appreciated 

I don't have a Supratek power amp. If I needed a lot of power and wanted to stay with tubes I'd seek out something along the lines of an @atmasphere or a @donsachs Kootenai.  If I didn't need a lot of power because I had highly efficient speakers (ala Klipsch or big Altecs) I'd seek out an Alan Eaton 45 stereo or monoblock setup.

One other thing that has really improved the sound I'm getting from my Cortese are some Cardas cables. I'm using old, but new-to-me Cardas Neutral Reference wires from DAC to preamp and from preamp to power amps. Also Cardas NR speaker wires. They're, like, 20 years old, but they are a huge upgrade for my system. Previously I just hadn't paid much attention to interconnects or speaker wires.

Thanks for the info and keeping the thread alive.  Didn’t know Mick still makes/sells power amps. I have a Decware Torii Jr V2 tube amp shipping any day after waiting 2 years to be made. Looking forward to seeing how it pairs with my Cab and 91db speakers.

Cables make a definite difference.  I have recently bought Audio Envy Power and RCA IC’s and had a wow moment.  Cap makes great quality lightweight cables that are well priced.  He really knows his stuff.  Also, my Revelation Audio Passage Umbilical cord another wow upgrade after break-in.  Couldn’t be happier with my Cab.

@sim_audio_nerd I asked Mick about his 6l6 based amp a few years ago. At the time he said he was so backed up with preamp orders he wasn’t making amps. Maybe he would be willing to now. 

I took inspiration from his 6l6 amp by having a push pull amp made without a phase splitter in it. Since the Cabernet has a great phase splitting transformer in it you can eliminate it in the amp. I highly recommend it!

As @isaacc7 mentioned,  Mick stopped making them back when Covid hit due to an extremely high backlog of Pre's need to be made.  I believe orders have since slowed down a little for him and I'd be willing to bet he would make or certainly consider producing some amps now if anyone was/is interested.   Certainly  reach out to him and inquire if so.   His amps NEVER (very rarely) show up on the the used market.  You can probably guess why,. ;-)

@jslateiv thanks! I have been in communication with Mick but I can't decide if I want a 300b or EL34 Supratek amp to go with my Grange..!!!!

I changed my stock rectifier tubes to JJ rectifier tubes in my Supra pre. The new rectifier tubes have about 30 hours on them. Bass seems to be lower than I am used to with the stock rectifier tubes Mick provided. 

Do rectifier tubes also need burn in? 

I'd say you're hearing the JJs as they are. Rectifiers are critical in the sound chain. 

Bendix 6106 appears to be recommended. 

@sim_audio_nerd take a look at my post above dated 12-01 on my experience with various nos and old stock rectifiers.  They do make a definite difference. Many of the ones listed are low priced.  I tried some pricey ones such as Mullard and the highly touted Philips 5R4GYS.  Like the Mullard it just didn’t sound any better than the US military brands on my system.  US ones to me had a fuller, meatier and warmer sound with nice highs just slightly less clear and bright.  Ended up selling the Mullard and Philips.  They just didn’t sound as good on my system to me but all sounded good.  Splitting hairs here…