New tube preamp


Hi,

I'm thinking of replacing my PS Audio BHK Signature preamp and was wondering if anyone has listened to the Supratek Cabernet 6SN7 and or the Linear Tube Audio Microzotl preamps or the LTA MZ3, from what I've read the preamp in both of the LTA's are identical. Both are very reasonably priced (under $5000.00) and both are tube designs. For the money they are both supposed to be giant killers. Thank you.

Scot   
scothurwitz
If you type in Linear Tube Audio in the Forum search you'll find some prior threads on the Microzolt; and if you do the same with Supratek you'll find some threads that might help you get your answers
What don’t you like about the BHK preamp?  I’d also add Don Sachs preamp to your list, which at $2500 with all upgrades could also be considered a bit of a giant killer.  
I recently replaced my solid-state preamp with a Supratek Cortese. The Don Sachs model 2 was also one that I was considering very closely because of how highly it is rated. I suggest you mainly seek out a 6SN7 based preamp whether it's from atmasphere or Cary or Don Sachs or Supratek. It's a wonderful sounding tube and these are great sounding preamp. Sorry I have no experience with the PS audio bhk.
If you decide to expand your search to include other tube preamps, you may want to add Aric Audio to your list. His preamps may not look as exotic as some on the outside, but it’s top quality under the hood, both parts and workmanship. He can also customize the preamp to ensure synergy with the rest of your system.
I've never been impressed with the BHK preamp - it sounds quite "soul-less" to me and left me underwhelmed.  In the under $5K range I'd be looking towards Don Sachs or Backert or perhaps a used Herron VTSP3A.
First of all thanks to everyone for your help and suggestions, really appreciate it. Soix, to answer your question, the BHK signature preamp is quite good and I’ve been very happy with it for over two years. The more I read about the Linear Tube Audio Microzotl pre and Supratek’s best sounding preamp, the Cabernet 6sn7 I can’t help but thinking both of those units will sound better then the BHK Signature. Possibly because both of them are 6sn7 tube based designs. The BHK uses 12au7’s. I value tonality and accurate tonal color and the two pre’s I am looking at are supposed to sound great and excell in exactly these areas. What I appreciate most about the Microzotl pre is that they FULLY break in everything they sell before they ship and they give you a 14 day return policy, they even pay return shipping. I wish every manufacturer would have the balls to do that! That speaks volumes to their confidence in the sound quality and there have been reviewers who have bought one after the review and it’s now their reference preamp (teajay) formerly of Home Theater magazine who now reviews gear for a well respected audio online magazine (I forget which one). I know teajay and respect his opinion and his ear.

Scot

The Lamm Industries LL2.1 is an exceptional vacuum tube preamplifier you may want to add to your audition list. It's a little over budget but in exchange you could be finished with your search and find long-term happiness.

I agree that you need to hear these things in your home, in your system to be able to make a choice that leads to that long-term happiness; find a dealer that will help make that happen.

- Colin

full disclosure: I'm a Lamm Industries dealer
https://gestalt.audio
My neighbor owns the microzotl and it is exceptional! He also owns the Don Sachs pre and it is exceptional! They are different sounding pre amps but both wonderfully musical. If your system is slightly bright or fatiguing, the Don Sachs may be the better fit. It exhibits a little more of the tube flavor to my ears. The LTA on the other tends to sound a little cleaner and neutral. They are certainly more similar than they are different. You can’t lose either way 😊 
You should try a Backert Labs Rhumba Extreme 1.3. I have the regular Rhumba 1.3 and it is very impressive.
I have the Microzotl preamp @$4500, and I can confirm that it sounds quite excellent. However, I cannot offer any comparative assessment other than I like it significantly more than the Parasound JC2 solid state preamp that it replaced.
and they call this an audiophile forum...Sounds like stock 12au7's to me. swap the tubes to nos. any amperex or simens 1950-1970 will sound amazing compared to stock (probably russian genalex).ge's are nice as well from the same era but my favourite is the mullard 10m 12au7 .i'm not arguing that the other models aren't good but if you want to make the most out of any tube preamp or tilt the tone to your taste just swap'em, swap'em good...
OP,
I do not own the BHK but, 2things have made a huge difference in my systems

* Machina Dynamica Super Stiff Springs
* XLR cabling, specifically Wire World

hth


Scot, I would also highly recommend looking at the deHavilland Ultraverve preamp.  I am currently using a Tung Sol round plate 6sn7GT.  The sound is very nice...detailed and deep with great bass.  I also recently had Kara Chaffee (the designer of the Utraverve) install Dueland capacitors and I am very pleased with the sonic results.  Other 6sn7's that I like are: Raytheon GT 231, Sylvania W's, Ken Rad GT's, or any military 5192's. I am running a Bluesound 2i streamer into a Chord DAC and then through my Ultraverve...which serves my Bryston 14BSST into B&W 802's. For my ears I think the Utraverve is a great bargain.  regards, Jim
I would also add Decware to your list. All tube design, pt to pt wiring. I own their amps, but not their preamp. 
For the gentleman who said “sounds like stock tubes to me” I am using some Nos Telefunken 12au7’s from the early 1960’s that transformed the preamp and made a huge improvement. I fully realize the benefits of good, nos vintage tubes from the 40’s, 50’s & 60’s and maybe even the 70’s. What concerns me about the Supratek preamps is the return policy. I’ve read Suprateks return policy and understand it’s a 3 day return and the customer pays the return shipping ($200.00 in my case) and you get your money back only after he sells it. I doubt if he sends you a fully broken in preamp which makes the 3 day return policy basically worthless. I don’t doubt you’ll eventually get your money back, everything I’ve read about Mick says he’s a very reliable and trustworthy person, it’s the amount of time you may have to wait that is a little concerning. It may take a week or two, it may take a month or two. Compare that to the linear Tube Audio’s return policy, first of all they fully break in all their products before they ship them, they give you a 14 day, no questions asked and they even pay the return shipping. What more could you ask for? The biggest and most important question though isn’t about a return policy, it’s about sound quality in your system and synergy with one’s equipment. Not an easy decision.

scot
Tomlhuffman,

I agree with our opinion of the Parasound Jc2. I found it to be very over rated. Frankly, it bored me to tears. 

Tweak1,

When you you refer to the Machine Dynamica super stiff springs, I’m not familiar but I’m guessing that they are some kind of isolation device/footer than goes under the preamp. I tried the Critical Mass Systems Center Stage series 2 feet under the BHK Signature preamp (they recommend 4 not 3) and couldn’t believe the improvement they made. It’s a very strange product. You place them under the component like any other foot but the sound quality gets WORSE, they even warn you about this in the instructions. Be patient though, after they have “settled in” which takes anywhere from 5 to 14 days you will simply not believe your ears. Everything gets better! The improvement is not subtle. It sucks because they are stupid expensive but once you’ve heard them there’s no going back, you’ll want to put them under every component. 

Scot
If you are looking for a great tube pre..try DHT tubes...fantastic.  Have a look at my Allnic L-5000 DHT on Audiogon now..thx  G
Home demo’ed the LTA and was not impressed. Did not live up to the hype. Different, but not a step up from the solid state preamp section on my Naim DAC/pre/headphone amp.  Ended up with a demo ET-7 Conrad Johnson instead. 

Be sure to listen in your home system and don’t  get sold on the hype. 
Meiatflask,

I’ve been dying to listen to the CJ and especially the Et7 but only one CJ dealer in my area and he doesn’t have one on the floor to listen to. Is yours the series 1 or series 2? Also, if I’m not mistaken I think the retail price on the new et7 series 2 is up to 13k! What did you have before you bought the et7? I heard an et5 years ago and was impressed. I read somewhere that the head of their service department bought the company from the original owners, it looks like he’s making some changes and bringing out some new products which was needed. You rarely see one of their products being reviewed.  Thanks.

Scot
Hey scothurwitz,   you want to get a really great sounding tube preamp ? check out the ( Rogue Audio RP-7 Preamplifier  )  It's next on my list.
Agree on DeHavilland Ultraverve. I bought a used one and love it. 6sn7 based is the way to go for my system. Quickly sold my highly rated and reviewed 12AU7 based preamp once I put the Ultraverve in. Then I had Kara build me a Mercury 3 with upgraded Dueland capacitors. I am keeping and using both preamps. The Ultraverve is a great deal used. 
Exron,

Like so so many of us after reading the reviews I to wanted to hear one (RP7) I had a McIntosh C52 which, in my opinion, was mediocre at best and I got the Mac at cost because I work in the industry. My local Rogue dealer offered to trade the Mac for a new factory sealed RP7 so we did an even swap. I made sure to put about 200 hours on the RP7 before coming to any conclusions. NOT impressed. Like so many other pieces it did some things really well. It was very quiet, clean, open, nice bass and good midrange but where it fell short for me is it had absolutely no tonality, I need more tonal color and accurate timbre and I was so disappointed in that regard. It bored me to tears!

scot
Since you have tried some decent preamps and they each bored you to tears, would you mind sharing the rest of your system? Your source of boredom is likely somewhere else in the system.
Hi ghasley

My system I have currently does not bore me to tears at all, it's actually pretty good (in my opinion). I am just looking to improve it and I think my preamp is my weak link.  My system consists of a Jay's Audio CDT2 dedicated transport (remember those), the dac (tube output and tube rectified power supply) is a newer company from England called SW1X Audio, I bought their Dac III Standard model, Black Cat Tron (one of their best) bnc digital interconnects, PS Audio BHK Signature preamp, a Pass Labs XA30.8 amp and Eminent Technology LFT8B speakers. Most people are not familiar with the speakers, they are a planar magnetic midrange/tweeter and a dynamic woofer in a sealed box. The interconnect and speaker wire and power cords are all Kubala Sosna "Emotion".

I am very happy with the transport, digital interconnect, dac, amp & speakers and all the wiring. I just feel that the preamp can be improved upon. Full disclosure - I had the BHK preamp, sold it to try the Mcintosh C52, found the Mac to be much less musical than the BHK and sold the Mac and bought the BHK again because it was more musical with better tonality. The Mac was solid state and I value tonality and tonal color most and the BHK pre being a tube design has that, the Mac did not. A good friend on mine was a PS Audio dealer so I got the BHK pre at his true cost each time so I don't get hurt when I sold it. I just want something better.

I also realize that I am very fortunate, I have a dedicated, acoustically treated listening room that has been dialed in over the last five years that allows me to really hear the differences between each component. You quickly realize the difference between a good component and a great component. The attributes I value most are accurate timbre and tonal color and the system has to be involving, it has to draw you in. It has to communicate the emotion message and above all it has to have great musicality. I don't care about the usual audiophile attributes like pinpoint imaging and soundstage width and depth, if it has those great, the attributes I mentioned above are much more important to me. The preamps I am looking at are the Linear Tube Audio Microzotl, the Supratek Cabernet 6SN7 and the Coda 07X. Not because of price but because they are supposed to be very extremely musical with great tonal color. If anyone has owned any of these please let me know. Thank you.

Scot








I tried the bhk pre for a few days and I wasn’t impressed. I have a coda 07x now and it sounds a little better than the bhk. I didn’t like the click/pop sound of the bhk when it reached different volume levels. I like the simplicity and quietness of solid state preamps. I had a plinius and now the coda preamp, they are both nicer than the bhk and modwright preamps I tired. I’ll probably try the backert labs preamp in the near future, just to give tubes another chance. 
Hi phastm,

Thanks for your response and thoughts.

From what I understand, there is a new Coda 07X that has some new design elements that improved the sound quality and supposedly made a big difference. I also understand that they kept the same model number so one can't tell when those improvements started (not very smart if true). So the question is, how old is your Code 07X? According to Terry London who posts on this forum often under the name of teajay just got one in for review (Terry is a professional reviewer for several online hifi magazines) and connected it to his main system and was very impressed with the new models sound quality. He claims that it's fantastic and sounds better than some very highly rated tube preamps and he's not a solid state kind of guy when it comes to a preamp. He will post a review on this pre in Stereotimes.com in the near future. I've know Terry for a long time and I trust his judgement and his ear, he has heard a lot of preamps over the years and he loved this new Coda 07X. I would like to hear one in my system. Thanks. 

Scot  






Sounds like a lot of what you’re looking for might be achieved with tube rolling. I’m far from an expert, but when you mention tone it makes me think you want more of what people refer to as old school tube warmth that more modern tube designs have largely eschewed in favor of a leaner, more neutral character. I’m not sure the BHK hybrid design lends itself to big shifts with tube rolling, but maybe one of the experienced tubeheads can suggest more pliable designs and tube combos for you. You may even want to pick a preamp based on the type of tubes it uses. 
Cat_doorman,

Appreciate your thoughts.

In my BHK preamp I got rid of the stock tubes after about 300 hours (which weren't bad) and put in some older nos Telefunken 12AU7's from the early 1960's and that made a truly unbelievable difference, it was like I went out and bought a new preamp, it completely transformed it. Once you've heard a good nos quality tube in that circuit there's no going back. Well worth the ridiculous prices they're getting for these older nos high end tubes you see on Audiogon and Ebay nowadays.

The more I read about tube preamp designs the more I find that a lot of people out there feel the 6SN7 is the best sounding tube to incorporate in a preamp for sound quality, when the rest of the circuit is executed  properly of coarse.

The two tube pre's I'm looking at (LTA Microzotl & Suprateek Cabernet) are both designed around the 6SN7 tube and both are supposed to have beautiful tonal color with accurate timbre which is exactly the qualities I'm looking for, among others.

The Coda 07X wasn't even on my radar until I talked to Terry London (teajay) who's opinions I value. He posts on this forum a lot and really has a lot of experience and an ear I trust and value. He's a reviewer and has heard more preamps over that last few decades than I could ever hope to hear. When I needed help with a cd transport I emailed Terry and he suggested a Jay's Audio CDT2. He described the sound quality and the build quality as being the best bang for the buck that he's heard in his system. He compared it to several other transports costing 2 - 3 times as much and the Jay's Audio costs and was very impressed with it and recommended it to me. I bought one and couldn't be happier. His description of the sound quality was spot on and the thing is built like a tank. When he told me about the Coda 07X he said it surprised him. He is not a solid state kinda guy when it comes to preamps yet he kept an open mind and allowed the company to send him one for an upcoming review (he's a professional reviewer for several online magazines). He said the thing was amazing. He claims it has beautiful tonal color and accurate timbre, and may be the best he's ever heard for a solid state preamp. He said it basically had all the best qualities of both a solid state and a tube preamp and we all know how rare and hard to find that is! I now want to hear one in my system. If I do I will let you know.  

Scot 
I have only limited experience with the specific pieces of gear you have in your system: the Kubala cables, just barely left of dead neutral and superbly transparent. The Pass xa30.8 is an exceptional amp. Before you dump the PS Audio preamp, which Ive admittedly never seen or heard, you may wish to try some different tubes. Ive listened to alot of 12au7’s through the years and the Telefunkens are not among my favorites for tone or texture. Could I suggest you drop in some NOS Cifte’s/Mazda’s for a more illuminating presentation or NOS Mullard’s/Brimar’s for a more fullsome, tonally saturated presentation.

No offense intended but you have such a variety of gear there that I would venture to guess that no one can assist you more than to blind guess along with you. I must admit though that Ive never heard of anyone....you are the first....who drives a Pass Labs XA amp with a PS Audio preamp. I use Audio Research in my main system and when I had a Pass Labs XA amp I drove it with a Ref5se and it was a terrific combo.

Good luck.
Several have recommended de Havilland as I listen to my Mercury 3 from Kara.  Terrific stuff!  Her preamp replaced my Manley Neo-Classic 300B with Taketsuki tubes, no slouch.  I recently reviewed it here, gave my impressions of the preamp and listed my system.
Given your stated priorities I’d reiterate my prior recommendation for the Don Sachs Custom Linestage. At $2500 with all options and a 14-day trial period it’s an attractive package. Someone who responded to another thread had a friend with both the Sachs and MicroZOTL preamps, and although both were excellent the Sachs had a little more tonally rich, which would seem to lean more to your tastes.  FWIW and best of luck.
One more thing. Have you tried running your system without a pre (maybe thru your DAC, etc) and see what kind of sound you are getting? I'm just not certain switching Pre amps at the price level of BHK will provide jaw dropping differences. You already tried tube rolling. One other thing, is 30 (4 ohm) solid state watts enough for your 83 db speakers?
Hi aberyclark

I do not have a volume control on the dac so I can’t run it directly into the amp. I have tried that several times with other DACs in the past but never thought it sounded better. I am the type of listener that feels the preamp is one of the most important pieces of gear in a system. 

I never tried tube tube rolling though. I did replace the stock factory tubes (after about 300 hours) and bought some nos Telefunken 12au7’s from the early 60’s and they completely transformed the BHK pre, I was shocked at how much better the sound got from top to bottom.

I recently bought some other nos vintage tubes from the 50’s and 60’s and I’m going to try those and see what I get. The BHK allows you to change a jumper inside that lets you experiment with some 6 volt tubes such as 6922, 7308, 7dj8’s (Bascom’s favorites). It also has another internal jumper that allows you to increase bias from 4 to 5 milliamps and the people who have tried it said they couldn’t believe the improvement they got from such a seemingly small change. So, I think the next thing I’m going to do is start with one change at a time and take my time and listen without jumping to any premature conclusions. I’ve never been a big believer in a quick a/b comparison. If I make a change I give it at least a week or two, too easy to be fooled into which is “better” and not just different.

The Pass amp I have (XA30.8) is class ‘a’ at 30 wpc @ 8 ohms and doubles to 60 wpc @ 4 ohms and doubles again to 120 @ 2 ohms and still has 12 dB of headroom! The amp is simply amazing for the money and not only does it drive those 83 dB speakers effortlessly but always remains musical. It’s the best sounding amp I’ve ever owned and I’ve had a lot of good amps over the last 40 years. 

I appreciate your your thought and input.

scot
One prior owner of 07x told me to ls27 arc was much better. Another told me a mid tier mcintosh integrated preamp section was better. Just fyi.
The BHK Signature pre offers a lot of options for tube rolling - uses 12V or 6 or 7V tubes depending on how the jumpers are set.  I would certainly try some of the 6V options before replacing it with a different preamp using those tubes.  I'm going to be doing some comparisons myself this weekend (I hope) between a BHK pre and an Audio Research LS28SE.  Should be interesting.  Please keep us informed on your findings/decisions.
I’m currently running my xa30.8 with a Backert Rhumba 1.3 pre into Vandersteen Treo CT speakers.  Very happy with the results! 
As I mentioned above, I was going to do some comparisons between an Audio Research LS28SE and a BHK Signature preamp.  I did.  Downstream of the preamp the system was BHK Signature 300 monoblocks and Magneplanar 3.7i's.  Balanced connections were used between the amps and preamps.  On a variety of music (pop, jazz, classical) I preferred the LS28SE to the BHK with either the stock Psvane 12AU7-S tubes or vintage Tung-sol 12AU7's.  In this comparison the LS28SE seemed to offer more detail and, while the width and height of the image was similar, the illusion of depth was greater with LS28SE.  The change to a pair of Tungsram 7DJ8's (switching the jumpers from 12V/4mA to 6V/5mA) altered the sound of the BHK considerably.  I still slightly preferred the ARC in that system (not surprising I guess since it costs considerably more), but the tube change in the BHK made the difference in apparent detail and depth much less.  YMMV of course.
Be sure to listen in your home system and don’t  get sold on the hype.

Or the hype here in this forum. 
Audition, audition, audition.