Favorite 300B: Sophia vs KR
Swampwalker, Al makes a very good point concerning the 'ma' value can very under different test conditions or machine used. My Takatsuki spec sheet said my tubes ma is 66.6 for both tubes. My friend has a digital tube tester and measured my tubes at 75.4 ma. Markus I`m really happy the Takatsuki worked out for you. They`re a lot of money but I felt the level of your system would exploit this brilliant tube`s quality. |
03-28-12: Charles1dadYes, to a considerable degree. Also, the bias conditions that the amp is designed to automatically establish are most likely different than the conditions under which the 48 and 80 ma numbers were obtained. 03-28-12: MaxmadThe Renaissance amps are cathode biased. This paper provides a good explanation of that. 03-28-12: PdreherI guess the fact that VAC supplied those tubes provides at least a little bit of confidence that the 48 ma tubes would perform well, as the 45 ma number is significantly less than the 60 or so that is marked on the tubes they supplied for my amp. Of course, chances are that the test conditions VAC uses are not the same as the test conditions the vendor of the 48 ma tubes uses. BTW, the other number on my tubes ranges from 5.7 to 6.1. I suspect that number is the tube's transconductance, aka mutual conductance, in "millimhos" (ma per volt, referring to the change in plate current that results from a change in grid voltage, relative to the bias point). 5.7 millimhos corresponds to 5700 micromhos. The original Western Electric 300B spec indicates 5500 micromhos under typical conditions. Best regards, -- Al |
Charles1dad, The new Takatsuki TA300B tubes are still breaking in. I've got 31 hours on them so far. They are truely a game changer in the Frankenstien amps. The highs are chrisp and well pronounced and the base seems much more controlled. It is uncanny how these tubes change the personality of these amps. You were right on with your observations and I want to thank you for this tip!!! I do notice improvement from session to session. I have not tried the BT's in the VAC 30/30's yet. Hopefully before weeks end I will have a chance. One set of my BT's is marked with 69ma and the other is not marked at all and worries me. The ones marked with the 69ma came from Coincident and the second unmarked pair came from an Audiogon ad and perportedly have 100 hours on them. I'm a little afraid of screwing something up. I'll keep you posted |
Paul, yes "ma" stands for milliamperes, and in this case refers to the plate current under some given test conditions (plate voltage and grid-to-cathode bias voltage particularly; perhaps also filament voltage if that is varied from its nominal 5 volt value). I talked to Brent about this yesterday, and I could have sworn that he said healthy tubes should measure in the 85 to 90 range.Paul, I would feel pretty certain that what Brent was referring to was the plate current as measured in the amp, when biased by the amp. That has no necessary relation to the 48 and 80 ma numbers the vendor quoted to Michael, because it is very likely that the test conditions (plate voltage and bias voltage especially) were different for those measurements than they are in the amp. The plate current numbers will vary dramatically depending on those test conditions. I would expect the 48 ma tube to measure much higher when placed in the amp. The uncertainty I have, as I indicated in my previous post, is whether or not a tube whose plate current is significantly lower than average when measured under a given set of conditions (as seems likely to be the case with the 48 ma tubes), will provide optimal sonic results when biased by the Renaissance amp. I don't know the answer to that question. BTW, do your VAC sourced Chinese tubes have any measurements marked on their bases, as mine do? Best regards, -- Al |
Swampwalker - I am far from technically savvy when it comes to tubes... but I assumed that "mA" refers to milliamperes. If that's the case, my VAC REN 70/70 Signature amp has a milliamperes dial on it and it measures milliamperes for each tube. In my amp, my VAC sourced Chinese tubes measure between 75 & 78 milliamperes, and my latest KR tubes are measuring in the 80 to 85 range. I talked to Brent about this yesterday, and I could have sworn that he said healthy tubes should measure in the 85 to 90 range. At this point, I have too much conflicting info to know which end is up. FWIW, the WE 300B spec sheet (which REN amps are based on) call out a max. plate current of 100 milliamperes, which is a far cry from the 48 mA option your dealer is offering you (assumes mA and milliampere are synonymous). |
Michael, I would definitely avoid the 80 ma tubes, on the basis of Kevin's indication that they might trigger the amp's self-protection mechanisms. I'm a little uncertain about the 48's as well, especially given that we don't know the measurement conditions. I would certainly expect that they will function, but the number is low enough to create at least a little bit of uncertainty in my mind as to whether or not they would be optimal sonically. I suspect, btw, that at least part of the thinking behind the vendor's statement is that cathode self-biased amps can be safely run closer to "the max" than manually biased amps. That is because the cathode biased amps will self-adjust as the tubes age, while if a manually biased tube is set near its maximum ratings, it may drift too close to, or even beyond, those ratings as the tube ages. As I say, I'm not certain that there would be anything wrong with using the 48 ma tubes, but I'm not certain that they would be optimal either. FWIW, btw, which is probably not much, the relatively inexpensive Chinese tubes that were supplied by VAC for my Renaissance 70/70 Mk III are all indicated (marked on the tube bases) as being around 60. Best regards, -- Al |
I will heed Kevin's advice, unless there is a strong reason not to, but Kevin was a little equivocal saying that the measurements needed to be put into context for him to be sure. The vendor has an impeccable reputation for honesty (even against his financial interests) and knows way more than I do about these matters. He said that in his experience w Shuguang and Psvane products: cathode bias amps do well with the higher plate current tubes, and fixed (manual) bias amps generally like the lower plate current tubes. I've sold across those recommendations a ton of times, but if I saw any trend in regards to plate current, that was the one.. So I thought I'd put it out there to get comments from people who understand the concepts behind this issue, which I most emphatically do not. |
Pdrehr- Got a response back from Kevin saying We have one customer running the Treasure tubes in a pair of Signature 140's. If I remember correctly, the tubes labeled in the 70's will occasionally trip the 300B Sentry protection circuit. If that is correct, then perhaps the "48" tubes would be the better bet.Comments anyone, before I order? Not trying to start a war, I am truly ignorant on these matters. |
OK, my vendor for the Shuguang BTs says he has 2 quads; one w plate current 48 mA, one w plate current 80 mA. Any thoughts on which might be best in terms of reliability/compatability w the Ren circuit. Kevin said he needed more info on measurement conditions which I am trying to obtain. Totally ignorant on any of this "ee" stuff so any help you can provide would be greatly appreciated. |
Markus1299- Very interested in your results. I will tell you that I really liked the BT CV181s in place of the VAC branded 6SN7s. Phaelon- Good idea, I should have thought of that. I do know that Kevin says that the tubes must be fully WE original spec compliant and I THINK he told me that mesh or carbon plates were not recommended. |
"I am concerned about the Sophia RPs in the Ren circuit." Swampwalker, thats a very reasonable concern but I dont think that you have to leave the results to chance. If you would like to try the RPs, I suggest putting Kevin Hayes in direct contact with Richard Wugang of Sophia to see if a tube set can be specked for your amp. |
My Ren 30 has the VAC branded 300bs so I'm pretty sure that I've got some untapped potential. From what I've read from VAC, I am concerned about the Sophia RPs in the Ren circuit. At $2K to retube, I've gotta be sure that they are not gonna go "poof" or worse yet, take out an OT if they fail. It really sucks that I only have a pair each of the KRs and the AVVTs (bought 'em when I have a Cary that used only a pair). Anyone got a pair or 2 of BTs they wanna swap? |
Hello, all, For those interested, I believe Sophia Electric is willing to let go of a few pairs of Royal Princess tubes over the next couple of days for $1000, shipped, a nice step down from $1200 shipped . They have not posted this on their website, but people who are on an e-mail list are receiving this offer, good for only the next couple of days. Just in case you needed some more ambiguity in which of the two tubes to purchase. Ha! Regards, Joe |
I received my Takatsuki's late yesterday and they are warming up in my Frankenstein amps now. Right out of the box, I,m hearing profound differences from the previous Black Bottles. I can tell that they take the Franks to a new level. I'll report more as things progress. I was able to purchase a lightly used pair of Black Bottles to go with the 2 from the Franks and I will install them in the VAC 30/30. Should be interesting |
I would also like to thank you for all your learning experiences and want to thank those who commented on my two cents. I will mention I like a lot of various female jazz such as Jennifer Warnes, Hollie Cole, Diana Krall, Melody Gardot, and Patricia Barber among others. On the male side I listen to many of the stunning recordings on the German Stockfisch label. To really find the soundstage I listen to classical and live recorded Russian choral music that are well recorded. For the past 3-4 years I have been listening to 45 tube amps. (Jeff Korneff and Yamamoto A08S) because I firmly believed that a 45 tube (on the proper matched speakers) had the most natural tone and timbral accuracy of any of the triodes and in ways they are king at low listening volumes with limited power reserves. However I am happy to conclude that the RP and Takasuki tubes sound much the same as a good 45 only on steroids. This is as high of complement as you can pay IMO. What you get here is pure music and no areas to really criticize. In a properly designed amplifier these tubes are very tonally accurate and simply make the speakers disappear with ease. Not much else I can add except I wished they were not so darn expensive as my entire stash of 45's (7 pairs of NOS) were about the price of one pair of these 300b's. Whoever said being on steroids was cheap! |
I just can`t seem to shut up on this thread. Gsm I`ve been eagerly awaiting your impressions,thanks a lot. Gsm you reminded me that I have`nt mention what music I use, I`m an absolute jazz nut(and seemto be getting worse).A friend and I reccently went to a local jazz club to see the young and 'very' talented guitarist Randy Napoleon who played with a sextet, beautiful music and up close sound(our table was next to the stage).These encounters always expose the full body and tone of these beautiful sounding instruments(lean,thin, edgy,nervous and clinical just are`nt present, nor bloated, flabby and slow) I`ve been attending jazz venues frequently for the past 22 years and it`s a wonderful time and what training for the ears! As a result of the ferequent exposure to the acoustic instruments and vocalists it seems when I listen to a system I can (it seems) sense/hear the artificial or canned sound of what some would considered high end- audiophile presentation. I`m in no way suggesting my hearing or taste is better than anyone else at all, just trying to explain my bias for context. My bias is heavily toward the organic,holistic tone,timbre and overtones of music with natural dynamic ebb and flow. My praise of the RP and Takatsuki centers on their exceptional ability to sound so natural and like real performances are present.They both push me closer to what I hear and also feel at the live jazz venues. This is my point of reference,so those who share similar a orientation my high appreciation for these two 300b tubes will probably make some sense I hope. |
Hi Onemug, I really appreciate your kind comments.The RPs have just over 40 hours and the Takatsuki 75-80 hours.Both tubes actually reveal their superb sound within 2-3 hours and just continue to get better and better, Onemug I agree with you completely concerning the enthusiasm and spirit of this thread.I`ve grown bored with the 'my component is better than yours' nonsense, or the 'you like 300b based amps amps? you don`t want "neutrual/accurate" sound type of logic. I hope other admirers of 300b amplifiers share their experiences and thoughts.Let the fun and information continue to flow. Regards, |
I must echo the comments of Charles and GWalt - although I do not have their analytic ability. First, my SET amplifier is made by the same company that made the PSET amplifier used in the HiFidelity of Poland review. Second, I listen mostly to classical (from soloist and chamber to full orchestra and chorus), jazz, and female vocals and only occasionally to classic rock. Both the Sophia RPs and the Takatsukis better the Shuguang BT by a lot. Comparing the RPs and the Takatsukis, however, shows the latter to be a bit more refined and to have an eerie liquidity to the overall sound. The RPs were a bit more bold and in-your-face. In my amplifier and with the music that I prefer. . . the difference was a bit more than the 97 to 95 points suggested by Charles. At the same price, I would buy the Takatsukis. Amtrans was a pleasure; the tubes arrived in a matter of days. However, Paypal charges a premium for the yen to dollar conversion; and the new price of the Takatsukis will be 140,000 yen . . . or 1680USD bumped up to 1730USD by Paypal. Conversely, the RPs can sometimes be found listed on Audiogon. Finally, it will be interesting to hear the WE tribute tube made by Psvane and sold by Grant Fidelity. |
Charles1dad, How many hours would you say you have on each pair? To all re this thread: Wow. 6 pages/over 300 replies...no negativity. I'm seeing that as the exception not the rule. Nicely done. I always enjoy Charles1dad's posts. They are fair, balanced and "wide" minded. Now I've added a few more peeps to my list. |
Phaelon and Ischronism, I and I`m sure Gwalt appreciate your comments.This comparing of upper level 300b has been most enjoyable.It confirms that a good quality-serious purpose 300b amplifier deserves(and responds) to better tubes. Buy the best tube that fits within your individual budget,you`ll be rewarded. It`s really something to experience the transformation the RP and Takatsuki can allow if your amp/system are up to the task.Both of them are good right out of the box within just a few hours and they are continuing to improve with additional hours. As far as I`m concerned a good quality amp with 'great' 300b tube combination mated with proper speaker just brings out the pure emotion,nuance and tactile realism of every recording I`ve listened to.I can`t imagine a return to solid state amplifiers again. They did`nt come close to this type of involvement(at least for me). There`s just something so holistic, complete and right with these two wonderful tubes. Expensive, yes are they worth it absolutely! |
I am in complete concurrence with Phaelon! The talent to listen, compare nuances, and put to words in a very easily understanding manner... Very excellent job, guys!!! I am currently using my backup pair of RP's. Rachelle Ferrell just sang "With Every Breath I Take" ( with Terrence Blanchard"s muted trumpet) "FOR ME". My butt got kicked very nicely!!. WOW |
Charles1dad, Gwalt and all others who participated in the 300b comparisons, THANK YOU!!! We all have a lot of fun on Audiogon with some of our rather silly debates, but this is Audiogon at its best - members generously providing needed information that is not being adequately provided by the audio establishment. Tubes can rarely be auditioned, and with some tubes now costing as much or more than the components themselves, this kind of thread is vital. At least two things have been established here: There are some very high quality 300bs on the market that perform to standards in the classic Western Electric tradition. Also tubes dont operate in a vacuum (no pun intended), they work with a circuit that has a substantial influence on how the tube sounds. As others experiment with these and other 300bs in their particular applications, I hope they will continue what Charles1dad started here and post their findings. Bravo!!! |
Hi Gwalt, I`m glad you posted your impresiions, as you say different ears, amplifiers and system. Ultimately we reached the same conclusion, both are very premium 300b tubes but the Takatsuki is just a bit better yet in this 'uber' range. You`re right, I also could be happy(indeed) with either.Based on my experience, they both justify their steep price if you`re after superior 300b sound. Well that`s the verdict so far with the Coincident Frankenstein MK II and the Border Patrol amplifiers.I wonder if the close ranking would change with depending on the amplifier in use? The Takatsuki allows a phenomenal emotional connection with music in my system. Regards, |
Swampwalker & Markus - Let me know if you end up trying the Takatsuki's in your VAC REN amps. Audiogoner "Wavetrader" tried Sophia carbonplates (not RP) in his 70/70 and, if I remember correctly he had at least three of them fail over a 2 year period... so the Sophia RP's might not be a good option for VAC REN amps. Given their local availability, I would have been very tempted to try the RP's if I'd know they would hold up in the VAC REN circuit. I know I'm taking a bit gamble trying KR 300B's, but Audiogoner "Waltersalas" has been using them in a 70/70 for a few years with no failures. The quad I'm getting are said to be gently used, and I'm getting them at a used price @ 60% of retail, so I figure it's worth a try, vs. spending $2600 on Takatsuki's that have no track record in regards to longevity with the VAC REN amps. Brent & Kevin @ VAC did recommend Shuggie Black Treasures from a sound quality perspective, but did not know how well they's hold up over the long run. But @ $600 a pair, there's not too much risk, relatively speaking when it comes to premium 300B's. |
Now that there has finally been some comment and comparisons done on these two heavy weight tubes I would like to add my two cents since I own both of them now and have done a good deal of listening to both. The comparisons were done in a Border Patrol S-10 EXD amplifier with dual power supplies through Edgarhorn Titan l speakers heavily modified @ 107db efficiency. Since this amplifier is a fixed bias and adjustible I set both tubes up at .685 MA (The recommended is .68-.70 MA from the amp. designer) and gave them some 50 hours of listening before a recheck of bias....more later on this. I will try to catergize what I think most audiophiles classify would find important and give you a descritption from there. Nuetrality: I give the nod to the takasuki as it extends top to bottom with no emphasis anywhere. The RP has very slight warm character in the midbass like you can hear the carbon plates at work. They pull this off however by still giving you the full performance and extension and both are as smooth as butter. Holograpic imaging: I thought the Takasuki was a little wider in the soundstage with greater front to back imaging. The RP was farther back to begin with and a more laid back character. In my set up it was like the Takasuki is row F and the RP is row M. This differs from Charlesdad comparison in my system....welcome to audio as both systems differ as well as our hearing. Musicality/Tone definition: The richer sounding tube to me was the RP but it is not night and day but I could characterize the Carbon plates of the RP. They still give you the full performance however just that a bit of extra fullness there if you need it. The Takasuki was simply the more nuetral sounding of the two. Quietness and definition/resolution: The nod goes to the Takasuki as there is simply more air and definition around the performance....things are easier to depict and it could be because the backround is simply quieter who knows. Both tubes are great here however as compared to the Psvang/BT and EH tubes I have encountered. Since I was curious on rechecking bias on the new tubes I rechecked after some 50 hours or two weeks of listening and found the Takasuki at exactly the same bias I began with .685 MA! The RP had moved lower and needed to be reset again. In the end I find them both very stable but the Takasuki was something special there as I have never experienced such stability. Maybe they liked my amplifier better who knows but thought I would share. In the end I doubt you will be disappointed with either and would classify both extremely fun to listen to in there own ways and could live with either and find myself very fortunate to own both. I like the Takasuki to be a better fit in my system but your MMV. My suggestion is to save up and buy them both as it is the only way you will surely know! I have limited time to join in the fun of the forums but from this please realize both tubes are leaders in their class and your system will likely bring out the best in either and you will have to be the judge from there. |
I want to thank Isochronism(Brett) once again for his very generous and trusting loan of the RP tubes to a perfect stranger. Brett, the RP must sound fantastic in your Wavelength amplifier,sonic bliss I`m sure.I know The builder of your amp likes the W.E. but I`d find it hard to believe they beat your combination(unless it`s true old NOS rather than reissue W.E. he prefers, and even then who knows?). Best Regards, |
The Royal Princess(RP) is really impressing me. It betters the W.E.reissue and the Shuguang BT(my base line 300b). The RP is not embarrassed by the splendid Takasuki and they have similarities though they`re not identical. Both excel at the highest level at the frequency extremes.Bass is full weight , articulate,impactful,well controlled with natural bloom but absent of bloat and flab. Both tubes are with much upper frenquency extension and quite airy,very resolved but natural(neither is analytical,edgy or harsh). Both are excellent in the midrange and posess full-realistic tone and body,detail is top level.Voices and instruments are just convincingly realistic very organic(not artificial hifi) How they differ, IMO these two are uber 300b tubes but I find the Takasuki is just a bit more suave,smoother and refine(I`m speaking in terms of small degrees).The Takatsuki is perceptively a bit more involving and nuanced.I feel these two are peers and in the same uppermost hierarchy of current production 300b tubes.The RP is just a little bolder and upfront(not in a negative way) both are vivid and have excellent and just beautiful color saturation and simply wonderful overtones/harmonic preservation. Maxmad did`nt particularly care for the RP in his Cary amp but I find it a great match with the Frankenstein. The Takatsuki is just that small but noticably better in the musicality-involvement area. On a very strict scale where 70=solid performance and 100= absolute perfection.In my system I grade the following, W.E.reissue =70(just did`nt impress vs the others in my amplifier) BT=85(very good all around) RP=93(excellent!) Takatsuki=95 (sublime experience for me) Best Regards, |
Pdreher, I just want to second Charles1dads caution with the KRs. I was going to purchase them myself, but the distributor was admirably candid with me about their potential for finicky behavior, depending on the circuit application. So I had my tech take a host of measurements that KR recommended and was consequently advised that my amplifier would require modifications. Thats when I went with the RPs. Best of luck; I hear there incredibly dynamic when they work. |
I was able to find a quad of gently used KR 300B's to try in my VAC REN amp... so I'm out of the running for the mysterious megabuck Takatsuki's. A part of me is sad that I won't get to try them, but the money saved by going with the KR's makes it a bit easier. If the Takatsuki's continue to get killer review's, I'll probably bite the bullet in a year or two just to see what I'm missing. Looking forward to following the evolution of this thread. |
