Preamp Deal of the Century

Jpms... So you went with the Foundation Research cords. The LC's have been an integral part of my rig for over 5 years and I could not live without them. When I remove an LC cord in my rig to try anything else it becomes an immediately step backwards.

Hello Amandarae. Firstly, Congratulations on your supratek acquisition...you will be rewarded in due time! I am certainly no prophet sir,however... I have a sneaky suspician I may be able to somewhat guesstimate the outcome of your next 100 hours of seat time in that wonderfully [so called] humble rig of yours. Sir: Your past and present equipment choices speak volumes. Yes,that mullard/amperex gz34 is a great rectifier and the logical place to start your journey. Rectifiers can make or break any good amplifier especially in a system of such high resolution. The speed and transparency of an Electrostatic speaker is ruthlessly revealing and leaves nowhere to hide. I am a firm believer in getting the tonal balance correct first and foremost in any given room, one will find the rest of the presentation much easier to optimize to ones preferred flavour.Infact.. you may be fine tuning your speaker placement in due time once the supratek has found its voice as the stage of the preamp is almost holographic in comparison to your known references. Regarding the 6L6's and blue gas. Do not be concerned, as many output tubes will exhibit that characteristic,just be sure they test above 90% on a tester. If you have logged in around 40 hours... the rectifier swap should be somewhat noticeable now as the bass resolution of the supratek is world class by anybody's standards.Be prepared, as the astonishing clarity and focus of the supratek is really going to come into its own in the next 50 to 60 hours or so.You will find yourself spinning all those treasured old lp's into the wee hours of the morning only to discover that you never knew they were recorded so well. Enjoy! Stay tuned and check back in. Cheers David

Hi Cello. Regarding the 6c45.... I have very little experience with russian tubes other than to say I am not very impressed with most of the ones I have tried whether they are output tubes, input tubes or drivers.As far as the WE 437a being a drop in replacement,sorry I can't help here,I am not so sure without comparing the tube data and curves. However,that said...not all of the russian valves are bad. The miltary version [6n23ev] equivalent of the e88cc/6922 is a very good sounding alternative to nos tubes,it is extremely quiet,very rugged and sounds nothing like the god-awful sounding current sovtek 6922. Bwhite....I am very surprised regarding your observation on the siemen cca relative to the telefunken in the phono of the cortese. I have both the Klimo merlin and the ARC sp-10 preamps that both employ the e88cc/6922 family of tubes. The klimo employs it in its line stage and the sp-10 mk2 throughout. In the sp-10's phono stage,the siemen cca trounces any other equivalent tube on the planet[telies,mullards,amperex's,valvos,or anything else out there for that matter] and it's the same conclusion in the klimo or just about any other application I have employed it in. Both of these preamps are legendary in the high-end industry and are fabulous sounding preamps by anyones standards. Yes... I really like the telefunken sound... but the cca is in another league and I would select any siemen equivalent e88cc,e188cc,7308 over the telie in any of my gear[other than telefunkens own cca version].The sound of a lot of nos tubes can be very system dependent and infact, the telie may be the one that works the best in the phono of the cortese. Most designers today are voicing their equipment with currently made tubes so tube rolling and experimentation is the only way to reach any conclusion. I must say...I am still somewhat perpexed as to the comparison though.

Hello Mlkiz. I use a grado statement MM with my syrah, however, the output is only .5 mv. Do you have any gain stage flexibilty on your new chenin? I would hazard to guess the 3.5 mv into the riaa stage of the chenin may be a touch high. The only way to really figure this out is to try it and see how it works. All the best.

Hi Jazzdude. I too have a ton of nos 6sn7's and was seriously considering converting my new cortese to accommodate the 6sn7 mainly because I wanted to compare it to my Syrah. Now... I am not so sure. Before I do so,I am going to try a bunch of nos 6j5's and equivalents. I am very impressed with the old 6j5 shoulder shaped glass bottles in the cortese. Unlike the 6sn7,there are many substitutes and electrical equivalents of the 6j5 that can be used to voice the cortese and they are certainly a hell of a lot cheaper to acquire than any of the better sounding 6sn7's.

Hi Slowhand. Yes... I have used it and would say it is a decent tube, but to be candid here.... certainly nothing to write home about. The best GTB tube I have used in the syrah is the GE 6sn7gtb sidegetter. They are very plentiful,inexpensive[relatively speaking here] and come in both brown base and blackbase versions. They really are a honey of a tube in the Syrah, very well balanced tonally with a very solid bass punch. Perhaps a little on the sweeter side of neutral.... however, bang for the buck... ya can't beat em! They can be sourced just about anywhere for not much more than the price of a new pair of sovtek or the Chinese equivalents.

Hi Slowhand. To the best of my knowledge, they are exactly the same tube. Every one of my examples[more than 50] seem to be identical in every way.... from the plates,to the micas and the side getters. I honestly believe they are all the same tubes regardless of whether they were labelled gta's or gtb's. General Electric made tons off these tubes over the years and many were relabelled for other companies such as Emerson, Philco,Raytheon, Westinghouse, Silverton etc. The 6sn7 octal was probably the largest single production tube ever made.

Hi Gang.I am curious. Has anyone here ordered the cortese with the 6j5 tube option? The 6j5 triode tube is basically 1/2 of a 6sn7 dual triode. The current market value of the 6j5 family and equivalent substitutions are very attractive when compared to the better nos 6sn7's. I think Mick used a pair for each channel for full gain in the line stage. What I find attractive with this toplogy is: it allows one the option of using just a single 6j5/channel for those with highly efficient speakers,or amplifiers with high sensitivity, or using two of these for higher gain without the switch in the circuit. Supratek preamps that employ the 6sn7 dual triode like my syrah, also utilize a gain switch for each channel to allow for this.I also noticed that the new Supratek Grange preamp also employs the single triode 6j5 as well as the currently produced clone of the rare Western Electric 101D balloon type directly heated triode in the line stage. There are probably more 6sn7's available to us for voicing the syrah or cortese, however.... the 6sn7 preferences in my syrah.....the tungsol round,kenrad blackglass, and the sylvania wgt metal are all obsenely expensive to acquire today and seem to be getting more so all the time. It seems that Mick has accumulated a supply of the nos 1947 vintage 6j5g and he is supplying that tube with the Grange. Any thoughts here?

Hi Gang. Yeah, the WE 350b's are certainly "crazy money" for use as regulatory duty... however... nothing else even comes close in my rig. Hey Bryan...glad to hear you gave the bendix the run-in time it requires, it is imperative with most any new tube, and even more so with full wave restifiers. One more extremely important parameter regarding full wave rectifiers... is that each side of rectifier must test indentical to the other side { or no less than 2 or 3% of each other} and at least 95% of a new one. I consider the bendix 6106 as the best of the bunch in both the Syrah and the cortese in my rig with the gz34 coming a close second. Cheers Gang

Yeah, some war.... I've got to hand it to Fatparrot for taking this dim witt to task and telling like it is. His last response is bang on the bullseye, blunt, to the point and very well written I might add. Well said Fatparrot.

Hey slowhand. Congratulations!

Jphii. hehehehe.....Congrats on finding a pair of the 350b's, a good price to boot. Regarding budgets for audio.... I hear you. Not to worry though,believe me.... investing in WE 350b's will make many traditional investments like real estate, stock market,classic cars,wines etc etc, look silly in very short order. Furthermore,your tungsol 5881's are a simple sell as they are always in demand,the guitar guys love them [for good reason]. There are a whole lot more guitar amps out there than audiophile tube amps. Oh yeah.... Cello words are very true here. Enjoy!

Hey Dennis The Menace. I am happy your pleased..They truly are terrific and my definitive tube of choice next to the WE 350b's. Enjoy! Slowhand,email me offline re: tung sol 12b4a's.

Hi Gang. Perhaps I should chime in here regarding the 6J5. The 6j5 is basically 1/2 of a 6sn7, whereby the 6sn7 is a dual triode and has two triode sections and the 6j5 has just one triode section.In the cortese,they both do the same job.For those that are interested,go to my post [ 09-09-04 ] Cello....Tung-sol rounds? It doesn't get any better than that IMO.I had better take this oportunity to thank you for the tape drive you sent me......Thanks again sir, you are a gentleman and a scholar. In my syrah, it inevitably boils down to the "voice" of either the sylvania 6sn7 wgt metal or the tung-sol round. With live jazz in an intimate small club setting or smaller chamber works etc, I love the tung-sol round here. Large classical recordings,or live power rock and blues etc... I prefer the voice of the Slvania metal. An interesting anology here and some food for thought.... To acquire nos sylvania metal based 6sn7 wgt's in a box, typically sells in the $200/pair neighbourhood [if you can find them] whereby the same vintage sylvania 6j5wgt metal with identical single plate construction will typically cost around $25-$30/pair. There are tons of different brands, vintages and flavours of the 6sn7 dual triode, however... for voicing the syrah in my rig,there are only 4 or 5 choices of 6sn7's, albiet all great ones. 1- Sylvania wgt metals, 2-tung sol rounds,3-kenrad blacks,4-rca greyglass gt and 5- the Ge sidegetters. By contast; there are also many choices and flavours of 6j5 as well as substitutes. Because the 6j5 was actually a precurser to the 6sn7, there were many types, from ST bottle shaped 6j5's, metal tube 6j5's, standard glass versions with flat plate construction,round plates and so on. Further more... unlike the 6sn7,there are also substitutes like the 6p5,6c5 and the 7193.To qualify things here gang. I am not saying the 6j5 is better than the 6sn7........just want to make everyone here aware of the options open to them regarding supratek preamps.

Hi Ethifi.The toggle switch on the top is probably set in tape out mode. Try engaging it to the other setting . Fiddler... I have not worked with any of the Cardas caps as of yet. Was contemplating doing the coupling caps in my Vac monos with them. If you do try this mod,please inform us as I would be most interested. The only Teflon caps I have worked with are the nos russian caps [as bypass caps]... they are suberb and very transparent.

Hi Gang. Lately,I have had quite a few emails regarding the 6F6 tube that I used for regulation duty in the Supratek.Some history: There were many versions of the 6f6 [a power pentode] that date back to the 1920's. They were predominately used as output tubes in old radios,juke boxes,TV's and some very early guitar amplifiers. The very first versions of the 6f6 types were all metal envelopes similiar looking to the first versions of the 6L6 and 6V6 metals [power tetrodes] which can also be used for regulation in the supratek. The metal 6f6 sounds dreadful in the supratek [same goes for the 6L6 metal] I have also tried other versions of the 6f6 glass tubes with flat plates that are mediocre as well. The "only" 6f6g tube to use in the supratek that will sound similiar to the we350b is the shoulder shaped 6f6g version with the round black plate internals. Appearance wise, these bottles are shoulder shaped like a we 350b or a gec Kt-66 style tube. "None" of the other 6F6 types will sound like these! I think our Bwhite posted a picture of my 6F6g back in the thread [ 02-21-04 ] Thank you Bryan. I believe the tube in the picture was made by either Sylvania or National Union and relabelled for Rogers. I have also seen this particular tube relabelled as Philco, Westinghouse, Marconi, Brimar,silvertone and Emmerson. Do search them out gang as they truly are oustanding in the Suprateks! Cheers

Hello Ongkaku. Not a chance! The CV345 is "not" a direct substitute for a We 350b.... not even remotely close . It's American equivalent would be a 12E1. Maximum DC voltage for the screens is 300VDC. The cv 345 is basically an octal based 807. There are thousands of Genelex CV 345/12e1's floating around and come up on ebay regularly and would typically sell for less than $10.00 each "and" they rarely get a bid.

Hi Slowhand. Yes, I have a mono switch on both my Syrah and Cortese as I too have many vinyl mono recordings.

Hi Gang. Jphii and Stiltskin, thank you for your kind words regarding my recommendation of the 6f6g as regulators in the suprateks. They still continue to be a revelation to me as well. Bwhite.... I am a little perplexed as to why the cv-181/ecc32's would cause that effect to the remote in your friends syrah, as I had none of these problems when installed in mine. That said..... I should clarify a few things here first. Although the cv181 and 6sn7 have the same pin out and can be substituted in "some" circuits.In actual fact....they are quite different electrically and one must be very careful here. The cv 181/ecc 32 has different electrical characteristics and parameters. The cv181/ecc32 has different mu,gm, bias points and also requires much higher heater current than a 6sn7. It also has close to 30% more gain then an american 6sn7, and will sound louder than the 6sn7 at equivalent gain level. Some will perceive this extra gain to sound better,fuller,etc . While I concurr that the bottle shaped ecc32 is a great sounding tube when optimally biased ....however, it should really be rebiased when used in the supratek and would sound even better if it was biased closer to it's optimum sweet spot. However... like a many tube circuits, "system synergy" is the optimum word here and is really what tube rolling is all about. Jpms.....regarding your concerns with gain and sensitivity issues of the cary 805c when paired with highly efficient speakers.I can assure you that there would never be an issue with any of the supratek gain options or gain configurations. The Cary 805c [when optimized and voiced with better tubes] has to be considered one of the finest sounding tubed amplifiers ever made and certainly top shelf by anyones standards.When paired with the Supratek, you have a synergy that is nothing short of breath taking! I use Tannoy Westminster [98db efficient] and powered them with the 805c for more than 3 years and I still kick myself for selling them. When I received my syrah [which has both a high gain/low gain switch]. I never had an issue with noise or any other glitch's with either gain setting. A very big caution here though; and a good example of what I was alluding to earlier! If you have acquired the cv181/ecc32 to substitute the 6sn7 in your supratek. Do "NOT" substitute these for the 6sn7 in the Cary 805c, the current draw for the cv181/ecc 32 is far to high for the filament transformer in the cary 805c and could damage both the amp and the tube!!!

Hello Sorlowski. I have never heard the manley neoclassic, however.... The 805c's partnered with the supratek is a marriage made in heaven. Far and away the best combo I've ever heard in my rig. They really seem to compliment each other in a synergistic way. The superb clarity and bass speed of the supratek seems to offset the rather soft and bloomy bottom end of the cary. The midbass/lower bass performance of the cary 805c is it's only real liabilty in my books, and surely must be considered one of the finest sounding amplifiers of all time. I'm still kicking myself for selling my pair, especially after hearing them again with a kr 300bxl driver tube[instead of the stock chineese 300b] Man..... what a revelation that was! Unfortunately... I didn't have my supratek at that time to hear this combo sing together. Bet you can't guess what my next pair of amps will be?

Hey Kenji. Yes sir, one of the best. Even better if you already have a pair to put in the preamp. Otherwise, I would suggest searching for a pair of the bottle shaped 6f6g's at approximately 25% of the genelex as they are every bit as good if not better. Enjoy your thanksgiving down there gang.

Hey Kenji. Na.... you better send those NU 350b's to me and I'll send you a fresh pair of 6f6g's. The 350b's are the undisputed heavyweight champions of all time. They float like a butterfly and sting like a bee! It just doesn't get any better! Enjoy!

Hi Kenji. Yes, think of both the genelex kt-66 and the we 350b's as an investment. The genelex kt-66 is a much sought after output tube and it's market value has near doubled in the last 3 years. [ they ain't making anymore!!] cheers David

Slipknot and mondie. Congrats and enjoy the ride. cheers David

Hi Ecmlee. I wasn't aware that Mick had chosen the 6c4 in the chenin.My understanding is mick had implemented the common 6922/6dj8,s along with the 6j6 for phono gain in the new chenin .The 6c4 is no longer being produced so I would assume Mick has a supply of nos tubes.What brand of 6c4 is in yours? The 6c4 is 7 pin single triode or basically 1/2 of a 12au7 dual triode. He probably selected this tube for it's superior linearity over the common 12au7. The 12au7 and deratives are rather mediocre sounding valves for use in high end audio circuits[especially phono stages]. That said: The 6c4 is notorious for being microphonic. I have repaired a few guitar amps as well as some older organ amps that used a 6c4. I think that Conrad Johnson also used the 6c4 in a few of their earlier PV series preamps if I recall???? The euro equivalent would be an ec-90. Mullard made a box plate version called the m-8080, this is a good sounding tube. Other equivalents for rolling the 6c4 would be a 6135 or a 6100.Because the 6c4 is prone to be microphonic and had me pulling out my hair on more than 1 occasion[read too many]. Are you experiencing any microphonics? I found the 1980's GE 6c4[grey plate] the least microphonic and most consistent of the bunch, however I preferred the extension and tone of the mullard 8080. Conrad Johnson should have a good supply of selected 6c4's. Hope this helps. cheers and all the best.

Hi Rabelais. No... The 6n23ev and 6n32eb are a substitute for a 6922/6dj8.

Hi Gang. Ethifi.... congrats sir and let the chardonnay run in for a good couple of hundred hours before tube rolling. You will be impressed right out of the box. A couple of hundred hours of run in time allows the passive circuit parts,wire and the transformer windings to settle in. Amandadarae...a great system sir and I can see a lot of time and thought went into putting it together... always love to see another great vinyl rig too. After reading about your previous wright preamp I can almost hear the musical "voice" of your system....you have good ears sir. Regarding the GE 6c4...Any of other GE 6c4 versions were just awful except for the 80's vintage versions. I believe Conrad Johnson still have select stock of these in inventory. I have to say I was not too impressed with the tone of the Tung sol's[hard treble range] and never really tried the triple mica Raytheon as the mullard m8080 won hands down. Furthermore.... The circuits I was playing with [organ amps and guitar amps] could never be considered high resolution amplifying devices like that found in a good phono stage. I did dig out my previous notes I had made on this tube. I had spent some time voicing a friend's Conrad Johnson PV 14 back in the early 90's and came to the same conclusion.... The mullard m8080 wins hands down.I have kept records that date back to the early 70's regarding the tubes used for voicing my own equipment as well as the stuff I've repaired or modified. I am not surprised with your choice of the telefunken e88cc in the phono stage. No doubt you have had previous experience with this tube type.The telefunken and the seimen cca are the very best of that family and by a wide margin I might add. If that particular tube does not seem that critical in the supratek's phono stage [as indicated in your last post] others here that do not wish to pay the insane price's those tubes currently command... may want to try the nos russian military tube in it's place. The 6n23ev is a terrific tube for use in a phono stage. It is dead quiet, accurate, great bass resolution, extremely well balanced top to bottom and consistently has the tightest matched triode sections of any manufactured brand of this family of tube. "Note"... It is not to be confused with the icy glare of the current commercial Sovtec 6dj8/6922 now being used in just about every piece of modern amplifiacation. The 6n23ev's were developed strictly for the russian military and were not even known to exist until the end of the Cold War and the demise of the Big Red Machine. There are surplus stock of this tube floating around.They are very inexpensive relative to most nos examples. Search them out, you will be impressed.

Sorlowski.A tall order indeed,although that pairing would definately not make good match with your thiels. I would seek out a high powered ss amp with big current delivery, preferrably on the warmish side of the fence. The big VTL's or perhaps a few other high powered tube amps may possibly be up to the task however, One should always try them first to be certain. best of luck.

Hi Rabelais. I have always been a fan of Roger Modjeski's progressive vacuum tube design, he has always been a pioneer in the audio industry. If memory serves, Modjeski was the first audio engineer to employ the 6dj8/6922 dual triode in an audio circuit and bring it to market. Infact...from it's inception, the 6922/6dj8 was never really designed for use in audio amplification as it was primarily used in early vacuum tubed computers.In those days, the 12ax7 and 12at7 dual triodes were the audio industry's standard tube, and they were employed for gain in line stages as well as phono stages.At the time...With the rapidly growing popularity of the extremely low output Moving Coil cartridges[typically below .5mv] It was quickly realized that the gain of the 12au7 family of tubes was inadequate for driving these cartridges without experiencing tube rush or noise. Roger was instrumental in implementing the higher gain of the 6922 family of tubes in audio circuits and almost every company in the high end industry followed suit and embraced the use of that tube. That said: I wasn't aware you could swap the 6bq7 driver for a 6922, as they are really quite different electrically. Unless he has configured the driver stage of the amplifier to use the tube in a cascaded type configuration or unity gain,then perhaps you could sub it[but why?] Do "NOT" try substituting a 6bq7 for the 6922 in your supratek as your just asking for trouble here!!! Trust me here.... even if it will amplify the signal, it will surely sound wrong. The same goes for any other amp or preamp employing a 6922 for amplifying the signal. Regarding the 6f6g's in the supratek.... if they are new right out of the box..... give em 20 to 30 hours of run in time to come into their own. The early 1940's Sylvania 6L6g's are very good regulators in the supratek [bottle shaped versions]and great sounding output tubes as well.

Hey Rabelais. A very appropriate analogy and very well said sir. Phase splitters are antiquated, inappropriate and should never even be considered part of the equation in the design of high resolution vacuum tubed circuits.

Hi Ethifi. I would heartily concurr with Swampwalker's recommendatations. A speaker change would definately have the biggest influence. Due to the dimensions of your room, I would opt for a standmounted monitor before a floorstander. There are just so many fabulous sounding monitors to choose from and many have some serious bottom end extension whereby you wouldn't even need a sub in a room that size. Mating a musical sub to most any quality speaker can be a daunting experience to be sure and rarely accomplished without spending some serious cash. There are some oustanding monitors that will embarass a lot very expensive full range speakers in a room of your size. I would hazard to guess that most any "quality" floorstander that I can think of.... would pretty much overpower your room. In my family room at home [21ft x 17 ft with an 8 ft ceiling] I am using a pair of reference 3a deCappo i stand mounted monitors and the bass extension and resolution is something to behold. Furthermore.... they are a rather benign load for any amp and are 93db efficient. I drive them with an 18 watt single ended tube amp with my supratek syrah and no need for a subwoofer period.They can be mesmerizing with well recorded source material. Many guest's have ask me where I was hiding the sub. Another truly incredible "full range" standmounted monitor speaker I would go "way" out of my way to find is the original proac response 2 with the port in the front,[ not the later rear ported 2's]. A top shelf near field monitor that will compete with most anything out there in my books and can be driven with lower powered tube amps as well. They have a bottom end weight with some serious slam down to the mid 40 hz area and a musical midband resolution to die for, not to mention the sweet and delicate tweet all proacs are known for. These can be had out there today for under a thousand dollars.I am sure there are many more made today that I have never even heard. Swampwalker's mention of the Merlin speaker for instance, The Merlin's VSM series floorstander can compete with just about anything out there regardless of price when properly set up and placed in the appropriate room. Perhaps a little too full range for your room dimensions however Merlin also makes the TSM series stand mounted monitor's that share much of the VSM's design and beautiful voice. While I have not heard the TSM monitors, I could only hazard to guess they would be first rate as well. Hope this helps and best of luck on your journey .

Ethifi. Yes, they are the speakers although I think his asking price is a little steap.Of the single ended amps you mentioned. The cary 805 wins hands down.

Hi Ethifi. They would be very good sounding tubes if they were not so tired. It is imperative that a full wave rectifier tests strong, a minimum 90% emission with matching sections[preferrably higher than 95%]. The tung sol 6L6's are surely just tired old pulls from a guitar amp. Don't even consider these in your chardonnay . ET....call home! [email me directly].

Hi Gang. Amen Tom.... best of the season to all. Cheers!

Hello K.D.occonor. I cannot help much on a direct comparison of the supratek to the ARC ref 2 as I have never heard the ref 2 in my own rig. I have owned and very much enjoyed many ARC products over the years. From the original sp-3a preamp, sp-6a to B, sp-8 mk2, sp-10 mk2 [still own] and a brief stint with the sp-11. For me anyway..... the last great preamp from ARC ended with the sp-10. I should qualify things here: I voice all my preamps with vinyl as my main source, as 90% of my listening is through the phono stage. ARC seemed to move into the high resolution, wide bandwidth camp with the introduction of the sp-11 series.I never really cottoned to that sound. For me it was far too clinical or bleached out and robbed the emotion and tonal integrity of the sp-10. I have heard the arc ref 2 on a few occasions in other systems and to my ear... I would still classify it in that same camp, albeit far more refined and articulate than the sp-11. Comparing the line stage of the older sp-10 to the supratek? NO Contest sir. The sp-10 is full bodied with a large and deep soundstage, a somewhat rounded bloomy bottom end and makes for a credible facsimilee of the illusion. However.... the supratek's line stage makes music sound more alive with emotion, it's abilty to retrieve that fine nuance and low level micro imformation thats masked or buried in lesser preamps. Added to it's uncanny dynamic range and bass weight adds up to getting you closer to the sound of a live event. It's clarity and coherency is unmatched in my experience.No contest here! You may want to post here where you reside and perhaps someone close will give you a listen. Even better if you could get a reference 2 for comparative purposes. All the best in your endevour sir.

Hey Pablo. A very nice post sir and I am happy you are enjoying the supratek. I am sure the chenin hasn't even come into it's own yet, as you will need at least a good 300 hours run in time to settle in. It just get's better with age! Your system is very well thought out and it's also great to see another vinyl rig. Tom[twl] is very well versed in the vinyl medium as well as the his many years of experience in the audio industry and IMO nothing beats hands on experience. A highly qualified mentor indeed. Re: 6f6g's. I service and repair old Juke boxes and early radios and generally have a supply of 6f6g's, however...I have exhausted my supply for many of the supratek gang here on this thread. I have contacted a few other of my techie freinds in a search for matched pairs and it's getting to be slim pickings out there. I am sure more will come my way as most of the techies don't give a damn what 6f6 they use. When they find them, I trade them 2 to 1 for new 6f6gt metals. PS: the 6f6gt metals are horrendous in the supratek. The coke bottle g versions with the round plates are what were after here however some of the smaller straight glass gt versions are really very good as well. Their are many 6f6gt versions.... some with flat plates and some with the same rounded plate construction of the coke bottle 6f6g. The rounded plate versions are the only applicable tube choice for regulation duty.

Hi Larry. Hope you and your family had a very Merry Christmas and all the best in the New Year! I didn't mean to suggest to Pablo to wait 300 hours before tube rolling... The new supratek or any other new tubed amplifier/preamplifier[for that matter] will become more focused and coherent with around 300 hours of run in time due to the transformers and the passive parts in the circuitry. Capacitors in particular are notoriously slow to form themselves to modulated frequencies. They take many hours to open up,particularly the top end. I would recommend we swap out the rectifier and regulators immediately [like right out of the box] as I have always consider that a no brainer.

Hello Kevin. Yes, Arc equipment is extremely well built and the product support is top notch, I repair or update all of my own equipment and have consulted with Leonard,the chief service manager at ARC on more than one occassion. He is a true gentleman and always very helpful and accomodating with respect to recommendations or technical advice. I am certain Mick at supratek would be as well. I have both the syrah and the cortese preamps and have never experienced a problem with mine.The build quality is top shelf. I acquired the cortese from a guy who was a 2nd owner. There were a few issues with the cortese as someone had retubed it with a bunch of tired old nos tubes. It was just dreadful sounding when it arrived and I am certain the poor guy surely must of wondered what all the fuss was about after listening to it as it wasn't remotely close to sounding like music! The mullard gz37 rectifier was pretty much toast and tested a little over 80% on one half of the wave and 90% on the other. The 6j5's [single triode]line gain tubes were so far from matched and barely made it past acceptable level on my tube tester as both tested under 80% emmision. The supratek or any other high resolution preamp with high gain is going to be very sensitive to tubes and I just don't understand why anyone would experiment with tired tubes. The suprateks can be voiced in different flavours depending on the gain stage tube of choice. For a well balanced warmer tone, one could choose the kenrad or perhaps the rca grey glass 6sn7.The tungsol round is a little more neutral, still warm and liquid sounding with a tighter bass reponse. The better nos sylvania's are somewhat more transparent with a leaner bass range than most of the other nos tubes. What I am fumbling around trying to say here is: The suprateks are very versatile regarding voicing and synergy with other components. And much like a fine musical instrument... they need to be fine tuned to your room, your ear and your associate gear. I still admire the phono section of my Sp-10 mk 2... the supratek is in a whole higher league. Furethermore... the supratek has the higher resale value ratio at this particular juncture.I can fully understand and appreciate if ones decision is to stay with the older and established firms in the industry because of reliabilty or service concerns. I have no such concerns with supratek as it is hand built to the highest standards,a simple straight forward topology with point to point wiring,top shelf passive parts and an architecture that is a work of art. PS: Regarding the old established firms? I much preferr the sound of the conrad johnson ART over the ARC reference. My 2 cents worth.

Hi Jpms.Both the PX4 and the 300b are direcly heated triodes with a ux4 or b4 pin out. Tubes that may be possible substitutions are the px25,2a3 and the 45. All are directly heated triodes traditionally used as an output tube in single ended amplifiers. You would certainly want to consult with Mick regarding substitutions here as all of these tubes are very rare and expensive. The 45 in particular is probably the most linear valve of the bunch and probably better sounding than the others. I have heard all of them as output tubes in amplifiers and they all possess a magic that most tubes only hint at. Very Intriguing indeed. Hope you post your findings here. cheers

Hello Braro. Your pre is in fact the Chenin,identifiable by it's tube topology in the phono stage. The original Syrah and the cortese phono stage employed the 6gk5 and the 417/5842 family of dual triodes. Mick elected to use the more common 6922/6dj8 and 6J6 dual triodes for the phono stage of the Chenin. Hey gang.... there are many nos substitutes or deratives for both the 6J6 and the 6922.The 6j6 can be substituted with many drop in deratives such as the British made m8081,the telefunken ecc91 as well as a host of many others. Regarding the 6dj8/6922 dual triode.It is a relatively common tube and for many years has been the tube of choice for the phono stage of almost every major commercial company. There are a lot of sonic flavours to the 6922 family of triodes although the best examples of the tube can be rather pricy for tube rolling experimentation. I am not sure of what brand of 6922 that Mick is supplying with the chenin but I would suspect the Chenin is delivered with a currently made tube from russia or china. If that is infact the case here, and if you think it sounds great now...WOWZA!.... I can assure all of you here that your in for a very major surprise here as any one of the 60's examples of that tube type from manufacturers like seimens, telefunken, amperex,mullard etc will just flat out "knock your socks off" as a substitute here, and give one a lot more options to voice and dial in the sonic flavour of the phono stage with ones cartridge of choice! Just a word of caution though.... The 6922 family of dual triodes can be prone to microphonics and can also be noisey right out of the box, never a good thing in any high gain phono stage let alone the supratek. Those here with a stock of nos 6922/6dj8/ecc88/ecc188's and cca's may want to roll them here and post your findings. For those that don't have nos stock of the 6dj8/6922 family... I have a relatively inexpensive tube recommendation that's a definative sleeper tube substitute here and with little risk or liabilty. I suppose we can call it a nos tube as it was actually manufactured strictly for the Russian Miltary before the Soviet empire's collapse. The 6n23eb can be found out there [with a little searching] and every example of this tube is extremely quiet, sounds nothing like the hard and glarey sovtek examples being manufactured today. The triode sections are tighter than any other example of this tube type including the legendary cca's from seimen and telefunken.

Hi Gang. Yes it seems that Mick has used different tubes in his phono stages, sometimes even in the same model of preamp. He has in past,used the 6gk5 and 5842/417a combo in the syrah as well as the cortese.His web site states he is using the 6J6 in combo with the 6922/6dj8 family. After reading some of the threads here,evidently he has used the 6c45, the 6j6 or equivalents in combo with the 6922. That said: All of these tubes are electrically similiar and are considered to be in the same family electrically speaking. Although some of these tubes may not be direct subs,they would be considered electrical cousins. There is good reason why Mick has elected to employ this family of tubes. As most of you know,his phono stage has extremely high gain and can drive even the lowest output mc cartridges available today without the use of a transformer or step up device. The 417a or equivalents,the 6j6 or equivalents,the 6c4 or equivalents or the 6c45 are all tubes with very similiar electrical characteristics. All have high GM, a high mu of around 50,low rp and high current. The 6c45 for instance, is a super tube choice for duty here, with it's closest american equivalent being the WE 437. His phono stages must be considered "World Class" by anyones standards regardless of what tube he has employed. Geez... A tubed phono stage to drive a .2mv cartridge was simply unheard of no less than 10 years ago! Don't get caught up or confused with Mick's choice of tube here gang,trust me.... he KNOWS what he is doing here guys...................... Sandro.... Order the Cortese and you will surely be unloading your ARC ls5 mk2 the very next day. As a long time and former ARC preamp owner, I have been a fan of ARC preamps since the ARC sp-3a from the mid 1970's right up to the Sp-10 mk2[ which I still own today] I have owned the SP-3a, Sp-6a, SP-8a MK2, and the SP-10 mk2 and enjoyed my time with all of them immensly. Furthermore, the ls5 mk 2 is "far and away" the best sounding line stage preamp ARC ever produced! Always musical,warm and engaging... a beauty to be sure. Unfortunately... It's not in any where near the same league as any of the supratek preamps, not even close for that matter. My Syrah simply stomps on the line stage of both the SP-10 mk2 or the SP-8 mk2 [which is basically the same line stage of your LS 5 mk2]. The Cortese is even better sir! Like killing two birds with one stone and looks like a win,win situation to me.

Hey Sandro. If you do order a Supratek preamp, be sure to keep the seimens 7308's your employing in the LS-5.They can be used for the phono of the supratek. They are the best of the breed in my honest opinion.

Hey Bryon. Yeah, good to hear you again.Hoping things are well for you and your family and all the best on your move.

Hello Larry. Congratulations on your new Supratek. I can appreciate Mick's take on tube rolling as many users with little or no experience with vacuum tubes can mess things up very easily with the use of improper substitutes,weak, tired or bad tubes and such.All the Supratek preamps are very precision instruments and designed with the tubes employed to operate within the specific voltages, tolerances and parameters of the tubes used in his circuit. That said: The supratek preamps are rather sensitive to the quality of the tubes used in the circuit and will certainly respond to a specific tubes sonic signature to "voice" the preamp in your system. I know the thread here is an extremely long one to read back through Larry but it would be in your best interest to browse back for references as many tubes will elevate the bar to a whole higher level than the stock tubes supplied with the preamp. You may want to type in my handle or Bwhites to reference our observations.Hope this helps.

Hey Larry and Raytheprinter. Congrats on your decision. As the gang here is saying... you will be duly rewarded. I intend on posting an update on the various nos tube options with respect the voicing of the cortese and the syra[chenin]in the very near future. cheers David

Hi Patrick. Yes, sounds like a classic case of phono overload to me too. Are both Syrah's using the same tube topology in the phono stage. Some used a combo of the 6j5 and 417a/5842 and others with a 6dj8/6j6. Are there any gain options on them ei: high and low. You mentioned you are using a high output mc... what is the manufacturers loading recommendation?

Hello Vetterone. Thanks for the prompt reply.Due to this abberation being common to both units and through both the phono stage and the line, I think it would probably be the most logical to start with the rectifier and regulators in the power supply. A weak rectifier or mismatched halfs of a full wave rectifier can have a profound effect on both the line and phono and can indeed demonstrate the characteristics that Patrick is alluding to. Can you test your rectifiers and tell me what rectifier you are using [5ar4, 5z4,5u4,5v4?? etc]as well as regulation tubes. Do you have any spare rectifiers around you can substitute? The regulation tubes are not likley the culprit here unless they are very weak or grossly mismatched as they do not have much influence on the tone per sey,but... rather more with spacial cues and air in the soundscape. Are you experiencing any woofer pumping in the phono stage? Try turning up the gain in the phono "Without" cueing the record and observe the reaction of the woofers. Is it a thinness that may be highlighting the upper midrange/treble range? Sorry to ask so many questions here sir, but persevere here and I am sure we can get to the bottom of it in time for Lugnut to entertain his guests. cheers David

Hi Gang. Hey Kevin, congrats sir. Abill, do you know the output of the Stanton? It may be a little high for the phono stage of the cortese and could overload it.

Hi Patrick.Hang in there partner. Steve is going to send me his syrah and I will try to source out the bugs in it. cheers David

Slowhand... Pay attention to Jazzdude's post here! Good catch Jazzdude. I wouldn't worry about damaging the capacitors, however as Jazzdude correctly pointed out....you must leave your preamp powered up or you will certainly experience a premature tube life of both the regulators and the 6sn7's. I do concurr with your observations of it's sound though, exactly the reason why I use the Bendex 6106 as my rectifier of choice in both the syrah and the cortese. The bendex 6106 specs out closer to the 5y3 electrically than any of the recommended "indirectly" heated rectifiers, It was developed exclusively for the US military to be used as a direct sub for the 5y3.Interesting though: Before I discovered the 6106, I was so very impressed with the sound of the 5y3, I would power up the syrah for about 1/2 an hour with the mullard gz34 in place and then "quicky" sub in the 5y3 to prevent the cathode stripping Jazzdude is alluding to.