Publisher Profile

Audio Note UK 4300E output tube

By: |

Introduction – Audio Note U.K. re-thinks the venerable Western Electric 300B

Many of you will be familiar with Audio Note (U.K.) and their plethora of tubed products. While these products, at least for me, represent the pinnacle of what can be achieved through thoughtful design and scrupulous choice of parts for their sonics when cost is not a concern, I have always had a concern when it comes to sourcing tubes. This is particularly the case with respect to the tubes utilized in my Audio Note Balanced Kegon amplifiers: a 5U4G rectifier, a VT-25 input, and two 300B output tubes. In each case, I have tried a variety of current production tubes, only to be dissatisfied with the end result. Consequently, I have found myself turning to NOS tubes, typically produced during WWII or the closely thereafter, much preferring their sound.  These tubes have become increasingly rare and increasingly expensive. This is particularly true for what has come to be my preferred 300B, which was produced by Western Electric prior to 1980, with older examples sounding even better but often selling for thousands of dollars.

Peter Qvortrup of Audio Note (U.K.) has made it a high priority to source new what was previously only possible with new old stock tubes and out of production parts, such as Black Gate capacitors, whenever possible improving upon the original. Working with tube manufacturer Psvane, he has researched and resurrected the best technology from the past, including but not limited to a Molybdenum anode 300B, which he has designated the 4300E. There is also a 211 version (4242E), but as I do not currently own an amp that utilizes a 211, I cannot really comment on that. Both the 4300E and the 4242E retail for $1,000 per pair.

Molybdenum is an extremely hard and difficult metal to work with. It has a melting point of over 3500 degrees centigrade, so very specialized tooling is needed to fabricate it. The cost of starting production is expensive and presents a significant barrier to entry. Concomitantly, the thickness of the plates can vary, making some examples glow red because the plate is slightly thinner than others. This is not a defect and should not affect reliability or sonics.

Audio Federation, the company’s Northern California retailer in Palo Alto near Stanford University, provided me two carefully matched pairs of the 4300E for review. These are currently available through any Audio Note authorized dealer. While these tubes sounded remarkably good straight out of the box, all listening tests were done after the tubes had been broken in for a minimum of 100 hours. My comments are organized by music selection with a conclusion at the end of the article.



In reading my remarks, please keep in mind that some of them clearly pertain to the subtleties of a specific recording and/or pressing; others to the specific sound of the 4300E’s. In the main, the 4300E’s are merely accurately reproducing what is in the groove.

Chris Connor (Bethlehem)

This is a mono jazz LP from Bethlehem’s better days. It is, effectively, a compilation of tracks Connor recorded in the early 50s. This was an early copy, with excellent sound, albeit subject to some limitations in the source material. Connor’s voice sounded superbly “present” in the way that some early deep groove pressings can. We had previously listened to the record using Western Electric tubes. With the new 4300E the sound of the voice seemed about the same as with the Western Electrics — terrific. The backing band sounded oddly “fresher” than previously. How does one describe an impression of the voice being better integrated with the band? What could the system be doing to bring that about? It seemed that the detail, including the ambience, was somewhat stronger than with the WE’s, which allowed Connor to sound more as if she were in the same room as the band. Most importantly, the record came across as very musical and a pleasure to listen to. Perhaps the WEs have a more seductive mid-range. I am not, however, pining away for it . . . so far.

Ansermet Crespin Ravel Scheherazade

This record seemed very musical in most respects except that it may have told us more than we really wanted to know about the recording technique and venue. Crespin did not sound like she was in the same room as the orchestra as there was more reverb around her voice than around the orchestral instruments. The orchestra sounded terrific — warm and natural. The voice, with the apparent additional reverb, sounded a little colder than I recollected from this recording.

Fennell Mercury Schoenberg Stravinsky

We were most interested in the Stravinsky on this late-50s issue of the LP. Aside from somewhat typical Mercury sound — slightly forward with some edge in the brass — the sound was excellent. Spatial presentation was everything one could want as one could easily point to the location of individual instruments. The instruments were well-rounded and they sounded about as authentic as recordings can present. I will be curious how this sounds with the WE tubes as a little additional warmth could be welcome. But this was a good listen.

Mel Torme, Lulu’s Back in Town, Bethlehem

Mid 1950’s Bethlehems present the most curious mono — you would almost think that it was some kind of early stereo because of the depth and the full middle of the sound stage as if the ensemble were spread out before you. The effect is fully present with the Audio Note tubes, as is the detail of Torme’s voice. The presence was at times remarkable . . . the breath, the articulation, even the distance from the mike. It was all right there.

I think that it is possible that the depth is not quite what it would be with the Western Electric 300B’s, but the Western Electrics might be less crisp. In any event, the sound drew me in and I found myself just listening and enjoying rather than worrying about those possibilities.

Debussy, Images (Paray) Mercury (FR2)

This is a very early Mercury stereo (90010) but is still a good listen. Instrument placement was very good, though the depth could have been better. The middle of the soundstage, as sometimes happens, seemed as if it could have been more realistically full; however, I do not think that was the tubes. The strings had good warmth without edge, but were more a mass of undifferentiated instruments than a section of individual instruments when the playing got loud. During softer, more chamberlike segments of the piece, detail and separation were quite convincing and very lovely. It is these more intimate segments that make the record an excellent listen. I do not believe that the imperfection I noted is an artifact of the AN tubes.

Mahler Symphony No. 4, Kubelik, DGG (large tulips)

This is an early DGG, a vaunted “Large Tulips,” that happened to be in superb shape with excellent sound. The AN 4300E tubes presented well, but not with the warmth that I would have liked.  Yet the sound was neither hard, shrill nor overly bright. In fact, the AN tubes deserve real praise for their detail and placement in the many chamberlike moments during the symphony. In those moments, it felt as if I were “right there.”  But, I have heard this record presented with a more luxuriant warmth that belies its age and provenance; DGG is not particularly known for these characteristics, although their recordings can surprise you.

Stravinsky Violin Concerto, Oistrahk (Phillips Plum)

This is another superb early stereo issue and it largely shined with the AN tubes. As seemed to be usual with these tubes the detail was first rate. Oistrahk is right in the room. Having heard the concerto just a few nights earlier played by the Houston Symphony, I was particularly curious to hear this recording. In concert, the solo violin had an unusual tendency to blend with the orchestra in such a way that I lost the thread too many times. The piece makes more sense to me through this recording (and the AN tubes). Of course, in the studio many imbalances can be righted, but with Oistrahk, I am thinking that was not a problem in the base case.

I have mentioned my nagging desire for more luxuriant warmth. The 4300E tubes do many — probably most — things really well. On this particular record, I was totally and completely absorbed by the performance. I was not thinking of whether or even if there could be more warmth.  Isn’t this where we all want to be when we listen?


The Audio Note UK 4300E tubes are somewhat more extended, particularly at the top, than the Western Electric NOS tubes, hence somewhat more revealing; however, this does not come across as aggressive or bright, grainy, or fatiguing. Indeed, the sound is very musical, if lacking the last bit of warmth one might find in a really good set of vintage WEs. With other contemporary versions of 300Bs I’ve heard, orchestral sound has tended to suffer; strings can be hard, or grainy, and generally fatiguing; brass instruments can sound edgy, winds can sound bodiless. That is not the case here. Surface noise issues are not particularly annoying with the AN tubes, which do a very good job of separating out the pops and tics from the music. In my Audio Note (U.K.) Balanced Kegon amps, the AN 4300E’s are sonically superior to the Takatsuki 300B and for that matter the wide range of other new production 300B’s that I have tried over the years (note that I have not auditioned the Elrog tubes). The 4300’s are somewhat more extended at the frequency extremes and somewhat more revealing, but with slightly less of the warmth and depth of the very best NOS WE300B’s, which have become almost impossible to find and command crazy prices.

For Dagogo readers who own Audio Note amplifiers that use 300B tubes, I strongly suggest that you replace whatever tubes you are currently using with the 4300E.  I do not think that you will be disappointed.


Copy editor: Dan Rubin

  • (Page 1 of 1)

19 Responses to Audio Note UK 4300E output tube

  1. Paul Parkes says:

    Fred Hi; This is a most interesting article. I have ordered the new Meishu Tonmeister (Phono Silver Sig variant) and have asked for these new valves. My particular favourite genres are baroque, and cantatas and choral works (though not opera). I’m given to understand that the timbral quality of the 300Bs is superb, and will also benefit cellos, violins, woodwind and other instruments. I also love Mahler, Bruckner, Beethoven, Haydn etc so your impressions of the former only serves to whet my appetite. My system should be with me in December or January (no rush – hand built products take the time they take!). I’m new to SETs and relish to running-in process for the system, which will also comprise CDT Two/II, DAC 2.1 Sig and E Spe HE. See and Vx silver cabling Oh yeah and S2 SUT for my veteran LP12/Ittok/Krystal front end. Thanks to the team at AN with a big thank you to Mario and Martin who have been stellar helpful. Not long to wait now. Would you or anyone else out there like a post on the First 100 Days…?? No sarcasm intended but its a monumental life-changing step for this lowly music lover…! Thanks again for your article.

  2. Fred Crowder says:

    Paul, I absolutely love your sense of enthusiasm! While I am basically an omnivore when it comes to music, most of my listening is classical and is similar in taste to yours, except that I would add Debussy, Ravel and Shostakovich. I agree that the timbral quality of the 300B’s is superb, and will benefit cellos, violins, woodwind and other stringed instruments; however, 300B’s do vary with some highlighting the midrange much more than others. With respect to burn in, the AN electronics will be very listenable straight out of the box, but will be noticeably better after 24 hours and continue getting better for the first 250 hours. Do note that merely having the units turned on is not enough, they really need music flowing through them for optimal results. Speakers are a different story. My Acapella Triolons needed about six months of off and on play for the woofers to really break in. Straight out of the box they were dreadful. I hope that this helps and that you will get back to us with your experiences.

  3. Paul Parkes says:

    Thanks, Fred. My musical tastes are quite catholic ie: a broad “church” (in the non-ecclesiastical sense). I have an extensive Anglo-Continental US prog rock collection too, including most of the vinyl I started collecting in the mid 1970s and a very fine Exile on Main Street which is unbelievable. I’m expecting the first three days of my new system to be a revelation – and for that to just grow, and grow..!

    It’s Music first all the way with me, with technical matters coming a long way behind – though I do my best to understand the context and relevance to the music listening experience. BTW happy for you not to post this reply if you wish, as it is very much intended as a “thank you” for your kind thoughts and advice. I am expecting to be moved, and to be able to connect with (say) the wonderful Alto Hertha Toepper (of Karl Richter’s Bach B Minor Mass DG 427 155-2 AAD) in a way that I have not previously experienced – though she/it brings me close to tears whenever I listen to her “hoch-Deutsch” rendering..truly uplifting, as music is intended to be. Thanks again!

  4. Sam says:

    I have a similar setup to the one you are getting. Regular Meishu 300B, same cabling et all. Regarding burn in – don’t judge the speaker for at least 200 hours. It will move from bright to dull and back and forth. Once burnt in the speaker will settle down and sound well balanced. However keep in mind that these are hemp foam surround drivers. Their sound is greatly affected by humidity and if you don’t use your setup for a while they will need to be run in for a few hours before they sound right again.

    Coming back to your Meishu. AN uses new production valves in their driver stages. These valves greatly limit what the amp can do. So you’ll have to change those as well if you change the output tube to really make the amp sing. I think the new Meishu uses a 12AX7 and a 5687. Try getting a NOS Telefunken smooth plate 12AX7 and a NOS Tungsol 5687. Try Brent Jesse for the tubes.

    If you don’t live in an area with high humidity you’ll do well with the AN setup.

  5. Fred Crowder says:

    Sam’s points are well taken. My Balanced Kegons came with current production tubes which quite honestly were not very good, particularly the rectifiers. Simply changing the rectifiers to NOS made a dramatic difference. The input tubes are also key.

    • Peter Qvortrup says:

      Hi Fred, did they really come with EH 5U4GB? They should have come with NOS 5U4Gs, clearly someone in the test department overlooked the fact that we normally run these amplifiers for at least 2 weeks, and for this we use the current production tubes rather than NOS types, the amplifiers then go into second test, where the NOS 5U4Gs are fitted, then back to run for a couple of days, then a quick test and then off to dealer. So it would appear we owe you a pair of NOS 5U4Gs. You can collect them when you visit the factory sometime!

  6. Paul Parkes says:

    Thanks Sam, much appreciate the input. As noted above, I’m a tube beginner, though have researched quite widely (that’s not the same as actually listening to different set-ups though). I heard AN first at the Bristol Show 2019, and it was the most musical to my ears, both with vinyl and crucially, with CD. I then had a home audition of a Meishu Silver Tonmeister with CD4.1x and J She – which sounded fabulous. I later asked Mario to demo a set of Es just so we could see if they worked in my room (which they did). I did a full cost review and decided to grow the budget to accommodate the suggestions from Mario and Martin (at my behest) got an augmented system built around the Silver or Silver Sig Meishu Tonmeister. I am indeed fortunate to be able to allocate sufficient resource for this to be the Silver Sig.

    How long did your CDT and DAC need to “gel” please? One of my main goals with this project has been to raise the quality of my CD reproduction – as it had become the only real source for new recordings through the mid 80’s onwards as soon as Polydor axed vinyl production and everyone else followed suit. My LP12 is fantastic even without Lingo etc etc, though it is Valhalla’d. CD is a priority, if only because much of my classical collection is in that form. I won’t be streaming for quality listening purposes, though may run my MacBook Pro through the DAC (or a DAC) to explore new genres.

    The cable choice Vx and SPE is as much intended to “help” the CD replay as anything else – its a gamble, and an expensive one at that, but one I hope will pay dividends in the coming weeks months and years of listening enjoyment. I can hardly contain my excitement Sam…!

    Thanks again for your post.

    • Sam says:

      Hello again,

      The CDT and DAC do not have to gel as such. I have the level 2 dac and CDT and they match up perfectly. However all tubes require burn in before they sound right. Tubes need about 50-100 hours before they settle down. I would advise not to tube roll the DAC 2.1x signature. I have tried doing so and still feel that the stock tube is better in this case. If you do decide to roll just go for the Telefunken 6DJ8 or 6922 because I believe that it’s better to keep the source neutral and voice the amplifier rather than the other way around where you just end up compensating for source deficiencies. The silver cables from AN are superb. Very well balanced, if a tad cool sounding.

      I once again repeat that tubes take about 50-100 hours to burn in. You can’t just plug in and plug out a tube and judge it. You’ll loosen your tube socket contacts overtime! When you plug in a new tube, you will have some idea on its basic structure i.e. bright, mushy, warm etc but it takes time to burn in and sound balanced.

      I have heard the 4300 tube from AN as well and it suits vocals extremely well. Lacks a little bit of attack, tension in the sound and bite if I had to add anything, but it’s not boring by any means. Its sweet, soft, bit 3D like in the vocals which it then builds around (this is the tubes centering in sound – every component has a particular aspect it tends to highlight come what may and builds around that center focal point). Fred can add his views on this too.

  7. Paul Parkes says:

    Fred, Sam; There is evidently a whole world of “tube-rolling” possibilities out there, and safe to say that I won’t be in too much of a hurry to experiment until I have gained a real sense of what I have invested heavily into (sonically, musical enjoyment being paramount). The 4300E 300Bs should make a difference right from the start – I want to let the system settle in well, before even considering venturing into an area I know next to nothing about!

    As for humidity, Sam, well I’m in South West England, so Northern European climate in a well ventilated, adequately heated house. Hopefully nothing to see here..!

    Brent Jesse – is that the one based in Illinois USA? I did “Google” it and had a quick look – quite an extensive site (if one actually understood what was being discussed..!)

    Fred, the Kegons are fairly high up the range of mono blocks aren’t they? Does not the quality of the other parts, such as transformers etc, determine the sound quality, with the choice of valve make giving different “flavours” of tonality? (If that makes sense?) I do find it somewhat odd to think that an otherwise expensive and carefully designed and manufactured product of that kind would have less than the most appropriate quality valves put in it! Of course, I may be missing the point here – are you saying that pretty much all NOS vacuum tubes from the original manufacturers will sound better than those manufactured currently?

    BTW a nice solid walnut Podium XL (V) equipment table from HiFi Racks UK arrives on Friday. I will also have refurbished, the venerable Target TT table upon which my LP12 resides.hopefully in time for the arrival of the new electronics. My friends (and my accountant) think I’ve gone mad!)

  8. Fred Crowder says:

    Paul, the Balanced Kegons are Level 5 AN AMPS which essentially means the best parts Peter can source, silver wound transformers, etc; however, they only have eight parts in the signal path (power supply is a different story), so each part or tube makes a real difference. In my case, the real culprit was the rectifiers which were made by Electro Harmonics. They were dreadful. The other tubes were acceptable but did compromise performance. I think that you are on the right track but please check the rectifiers to ensure they are not Electro Harmonics. Note that there are good current production tubes out there at reasonable prices.

    Good luck,

  9. Sam says:

    Hi Paul, I had a long email exchange with PQ regarding them not using NOS tubes in their higher selling products. PQ was kind enough to lend me a ear before explaining that it isn’t possible to source a consistent stock of NOS tubes. The older Meishu for example uses dual 5687 tubes in the pre stage. It is their best selling amp. So if they sell 50 Meishus in a year he’ll need to have at least 100 pieces of the 5687 tubes in stock. When you start sourcing NOS tubes you will notice that tubes from some vendors don’t last as long. That is why I recommended Brent (yes from Illinois). I’ve sourced a lot of tubes from him and he has never ever sold me a dud.

    I’ve tried tube rolling in cheaper Asian amplifiers and those amps simply do not bring out the capability of these tubes. Since AN uses better components etc you will hear minute differences. I’ve given you what I believe would be the best combo foe your Meishu. Do not tinker with the dac 2.1x tubes. The original Voshkods sound great in it.

    I’d end this discussion by saying that audio is like whiskey. Some like their’s peaty, some like their’s smooth. AN stuff is like a whiskey with a complex dense body (harmonics and tone) with a touch of peat (just enough bite when setup well) if I had to summarize it well. And their timing is spot on. That’s the AN sound as per my ears.

  10. Jim says:

    Hi Fred, great review. My 4300E’s arrived just after one of my rectifier tubes 5R4Gy went out in my AN Baransu so I have not been able to try them. What rectifier tubes would you recommend I use. I ordered some RCA’s (1950’s)to tide me over.
    I use WE 330B’s from the 1950’s and am excited to get these 4300E’s glowing.

  11. Paul Parkes says:

    Fred; Many thanks for the explanation – I have heard of the rectifier tubes you have concerns with – but have never gone into the specifics of which tubes were actually in the products being auditioned – maybe I need to start.

    Sam; again many thanks for your comments. I love the whiskey (especially so of single malts) analogy – it is very apt I think!

    I will post a reply at some future point when the system is installed, and I have had an opportunity to listen to my (many) favourite genres, composers and performers during the first 100-200 hours or so.

    My excitement and anticipation grow daily, but, I’m still able to appreciate and enjoy my (soon to be nephew’s) current set up!

    I have a special gold, double-casked Macallan (I think 25 year) single malt unopened ready for the evening of the Inauguration Day!

    Thank you both v much for your kindly thoughts and advice, it is v much appreciated!

  12. Fred Crowder says:

    The rectifier that I am currently using which is the best that I have found is a GEC U-52 which is hard to source given its age. I understand that the WE 274B may be better. Two others worth considering are the red base RCA and the Nationals, all NOS. Each has a character which may or may not enhance your system. The RCA’s (red vase) were very nice but a touch soft. Another RCA might be very different.

  13. Jim says:

    Thank you Fred, I appreciate your response regarding the rectifiers and will keep my eye out for some of those. The quick stand in RCA’s rectifiers arrived so I replaced the WE 300b’s with the new 4300E’s and straight out of the box they sounded wonderful. I could never articulate it the way you do so well but I can concur with everything you wrote about this amazing tube. I always felt my WE’s were somewhat “seductive” but now I am not sure I can go back to them as the new AN gems just sound so much more “real” (after only 20 or so hours). I will give the 4300E’s a run for a few hundred hours before I swap back the WE’s and report back. And who knows, maybe my preorder for the new WE 300b’s will show up one day (not holding my breath) and I can do a shoot out:)

  14. Alan says:

    I recently added these tubes to my Cary Audio CAD-300SEI replacing Genalax Gold Lion 300Bs. It’s like a whole new amp. Better bass, silkier highs and just so musical. It’s just not fair that all you AN guys think you can have all the fun.

  15. Fred Crowder says:

    I am glad that you gave the Audio Note 4300E tubes a try. They deliver a performance level that is far beyond what you would expect for the price. Readers sometimes assume that everything which AN makes is incredibly pricey, but that is not the case. For instance their Isus power cords are very good and priced reasonably. In any event, I wish you good listening.

  16. Grant says:

    Hello Fred,
    A little bird told me you have recently completed another 300B comparison. What insight might you offer regarding 300B for Audio Note P4 monos? I presently own 4300E, which sound terrific.

    • Fred Crowder says:

      Yes, I have again been listening to 300B tubes from various sources. While I want to do a bit more listening before writing anything, I can say that unfortunately, the original tubes made by Western Electric remain head and shoulders above the rest but they are hard to find and outrageously expensive. The next in my hierarchy are the ordinal re-issues made by Charles White before he moved the factory to its current location. I am still evaluating his newest re-issues but initially do not like them as well as his original re-issues. I still think that the AN4300E is hard to beat for the money but not in the same league as the others. More to follow.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Popups Powered By :