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300B功放用家专栏 [复制链接]

1#

300B Comparison Review



  May i first set the "ground rules" here.  Instead of some geeks idea of going through all the manufacturer's claimed measurements and stuff i decided to do all this just like any normal dette/dude would.  That is, as drop in replacements to whatever 300B tube might be in their existing unit(s).  The main monoblock amplifiers used during this review were the very impressive and highly regarded Wavelength Audio Cardinal made by famous tube dude Gordon Rankin.  The Cardinal is a self bias unit with the B+ set at 400 volts with a median current of 65-75 milliamps.  The AC heaters are 5 volts.  This seemed very sane and very standard so it was a "known good".  Tube rectification duties are from my head stash of Mullard brown base CV1377 (military grade GZ34).  i will mention that some tubes were also tried with the Valve Art tube amplifiers which i also find very impressive and could also adjust the bias setting.  What obviously complicated matters here is that, say, the KR Enterprise tubes and the more powerful Valve Art 6300B did sound better when used with an amplifier which was designed specifically for these higher powered, he-man wimp haters 300B-type tubes.   In the end you should only take the below review as a possible guideline if even that!  An equipment manufacturer can, of course, "flavor" his unit to make a certain tube sound best by specifically designing the "sound" of the circuitry around said tube.

Lastly, i did try the Audio Note / AVVT tubes and it worked and sounded wonderful... until it blew up within a few hundred hours, some hours in the Cardinal, the rest in the Meishu where it self destructed, taking with it part of the Meishu's power supply!  AVVT has since changed the tube and it now sings gloriously, yet at the time of this review we did not have the newer version for full review.  If you have a working pair of them consider yourself very fortunate.  The  Tesla 300B is the same as the JJ Electronics as reviewed here.  And now on with the real show!

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The Centron 300B is one of the only two made in the USA 300B tubes (the Western Electric being the other). The audio products division of Richardson Electronics Ltd. are also the keepers of the Bugle Boy name by the way.  i tried to love 'em.  i really did!  Alas, they were so hazy as compared to other tubes here that in my listening they ranked dead last.  i don't know what more to say.  They just seemed slow, hazy, and just not nearly as good as the rest of the bunch.  Not much in the way of microphonics by the way but even if it was totally dead microphonically speaking i still couldn't recommend it due to music reproduction quality issues.
Richardson Electronics, Ltd.
40W267 Keslinger Road
P.O. Box 393
LaFox, IL 60147

voice (630) 208-2200
fax (630) 208-2550


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This tube by Valve Art was one of the reasons why this review has taken so long to hit "print". It is absolutely amazing and i just received them about 2 months ago and wanted to put them through the ringer (making sure these weren't like the AVVT Audio Notes).  Heck, it was my closet fave... until.   No it did not blow up, just that another tube even more recently came my way here within the past few weeks of this writing which blew it out of the head contender position for the best 300B variant for GI Joe drop and go action.  The Valve Art 300B-C60 is actually in the middle of their 300B product line.  They also offer a lower line tube called simply the 300B which one of my friends says betters this one!  Since i only got the middle of the line unit seen here and top of the line 300B (seen below) all i can say is that this was the best i had heard at the time over all others except for the winning tube.
The mids are not quite as liquid as the Western Electric, yet what is?  The bass is more extended and defined the the W.E. though.  The highs are very smooth and defined as well nudging out even the W.E. if you're looking for more upper end extension.  The inner resolution was pretty much the best in the bunch too with a tie between it and the all out winner in some regards.  One of things you'll notice with the Valve Art is that they use small flat pieces to keep the very small wire strands in their place at the top of the tube.  Most manufactures just solder a small connecting piece to keep the tensioning of said wires in place.

The microphonics were very small, yet still evident when i played my system at louder volume levels.  Microphonics can really effect the imaging and this was evident, though to a small degree.  Let's please keep microphonics in check here because if you can better isolate the amplifier from floor and air vibrations then this helps to reduce microphonics to some degree.  In fact the new Vibrapods really helps here as i now use them instead of the usual feet for the Wavelength Audio Cardinal monoblocks.

A real winner here and almost a tie with the REAL winner, yet the REAL winners subjectively has better resolution and were just a teeny tiny bit less microphonic too.

Valve Art
International Electronics Building
Yingbin Road
Changsh, Hunun 410011
P.R. Chine

voice (86) 731-442-8169
fax (86) 731-445-6999


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This is the top of the line tube by Valve Art.  It uses the "upgraded" ceramic base and has other "improvements" which allow it to be driven with a higher plate voltage and current which, in turn, increase the wattage output.  What amazed me, and was also confirmed by a friend of mine who has also played with many 300B-type tubes, is that this tube was worse then the cheaper lower line of Valve Art as reviewed above!  Although i did try it using both the normal and also higher bias setting in the Art Audio amplifier, it seemed to definitely sound better driven with the higher setting.  Unfortunately when she clipped, it was hard and nasty.  i mean nasty nasty as in the mids all broke up horribly.  The worst clippers in the whole 300B-type tube bunch here (worse then the Centron too).  While i can not recommend this tube as a 300B direct replacement, it does have some good qualities when used at the higher bias operating guidelines for higher output.
Ramping up the bias to the higher setting seems to make the mids smoother, the higher a bit more liquid, and the bass is really full here.  Still, the mids and highs sounded better with the lower line Valve Art 300B-C60 then with this upper line 6300B tube.  The only advantage for using this upper line Valve Art over the middle line would be for more (maybe a tad too much) bass.  On virtually all levels the middle line tube was better then this one if we compare them at near their proper operating guidelines as they were used in the Art Audio unit.  Still, when used as a simple drop in replacement for whatever non-testosterone 300B you'd be much better off with the 300B-C60 then this higher priced ceramic based 6300B in my humble opinion.

Valve Art
International Electronics Building
Yingbin Road
Changsh, Hunun 410011
P.R. Chine

voice (86) 731-442-8169
fax (86) 731-445-6999
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2#

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Part of the hold up on this entire review has been, well, just as i found a killer tube like the Valve Art, another tube would come along and blow all others away when used as a direct normally electrically run 300B. These new JJ Electronic 300B tubes made in the Slovak Republic have won my heart as the all out winner of this grouping in my systems to my ears.
Although a bit microphonic, it seems to have the best balance of smooth mids with upper and lower frequency extension in my beloved Wavelength Audio Cardinal amplifier.  If fact i love it so much it now pretty much permanently resides on it as part of my main reference system, only giving way to the WE300B when i desire a more, um, seductive sound.  Ambience and imaging are excellent as it inner resolution too!  This is the latest 300B to arrive here in my humble abode and also the best so far for direct replacement on a normally run 300B amplifier.   Some of you might worry about a bit of that blue glow on the top, but then again so did the WE300B have that at the beginning too.  i feel there is just too much emphasis on that top blue glow.  Yes, it does mean a few things, yet it's not necessarily gonna make your system sound like junk, burn down a small village, and release a nuclear warhead on your government.  Sheeesh, relax and enjoy the music!

The JJ Electronic 300B seems to have all the things i love about 300B tubes!  What more can i say then that?  May i humbly suggest you try the JJ Electronic 300B?   You too might find yourself in love while enjoying the music.

Valve Amplification Company
807 Bacon Street
Durham, NC 27703

voice (919) 596-1107
fax (919) 596-2037

www.vac-amps.com




  In the end i have realized that as each newer 300B variant is reaching the market, they seem to get better too!  This is great news for those of us who love our 300B-based amplifiers.  After all, how many solid-state amplifiers can you quickly and easily change the output device(s) to subtly modify the sound of the music it reproduces?  None!  Of course the electrical operating dynamics of each tube and the amplifier it is used in can also alter the sound too.  Therefore, a manufacturer can customize their units to get the best sound out of a given tube (though the Centron was so bad i can hardly see where it could "win" here in any unit when other tubes are dropped in as replacements).   Of course there is also personal preferences to be accounted for.  The WE300B is a known good though it, too, has limitations.  The KR Enterprise 300BXLS is amazingly good as a simply drop in replacement, yet is slightly beaten by the JJ Electronics.  Alas, the JJ can't hold a candle, per se, to the 300BXLS if the amplifier is geared towards the optimum specifications of operation of the 300BXLS.

i have avoided putting prices in the reviews of each tube because the prices can vary from country to country.  To generalize, the KR 300BXLS is more expensive then the JJ Electronic by a factor of two or more here in the USA.  The wonderful Valve Art 300B-C06 is priced at about the same as the JJ, yet in the end the JJ edged out the Valve Art.  This was a small difference though.  To each their own.  Of course your own preferences and system may dictate, say, a more powerful amplifier using the 300BXLS yet i have kinda assumed here (uh oh) that you already have a normally run 300B amplifier and are looking for a replacement which just may make your amplifier(s) reproduce music to a higher standard.  In the end what really matters to me is that you...

     Enjoy the music,

     Steven R. Rochlin



PS: This review was conducted in late 1999 or so, Thorsten Loesch has a review of newer 300B tubes conducted in December 2001. Thorsten's review is available
http://www.enjoythemusic.com/magazine/equipment/1201/300b/
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3#

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The KR Enterprise company has been making their very own, unique variants for a while now.   Various designs by Ricarrdo Kron have been fine-tuned over the years.  Higher purity of chemical, stronger vacuum within the tube itself...  These all add up to better music reproduction capabilities.  The VV302 is another one of their 300B-on-steroids variants.  Using a cool lookin' blue glass and flat top this tube is quite good, yet just a bit too bright for my tastes when used as a direct replacement for a normal 300B.  When used with an amplifier optimized for it though, it can really deliver the good.
The highs seem to smooth out while the bass tightens up.  Here is a very rugged, reliable tube that might be a bit microphonic, yet with some simple vibration control devices (like Vibrapod feet), they can be truly amazing.  Deep frontal soundstage with solid imaging with a nice hall decay when the recording has it.  Still, it left me just a tad bit cold.  The mids weren't as smooth as i with they were.  Still, they are very impressive.   Of course as time has passed since this tube was introduced, there is another.   Namely the KR Enterprise 300BXLS which is reviewed below.

KR Audio Electronics
Nadaemlejnska 1/600
180 72 Praha 9
Hloubetin 6904
Czech Republic

e-mail: kr.audio@tiscali.cz
website: www.kraudio.com
voice/fax 00420 2 66107168
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With this newer generation of 300B variant, KR Enterprise really have a winner on their hands in my humble opinion.  When used as a direct replacement for a normal 300B, the 300BXLS has all the good stuff the VV302 has yet with a smoother midrange which i had hoped the VV302 had.  Also, the bass seems more tight and tuneful too.  To add to all this, the highs are gorgeously smooth with impressive upper frequency extension.  This is something the Western Electric 300B tends to really lack in.
Sure the WE300B has a lovely midrange which seduce many people including me, yet the lowest and highest octaves suffer a bit to my ears in my systems.  If you can juice up the bias and voltages a bit, the 300BXLS can be utterly amazing.  It's what you might have really wished Santa Clause brought you for Christmas instead of that lame necktie!  MAN, Santa needs to get a clue!   If you have one of those testosterone-driven super 300B variant amps the 300BXLS could be "all that and a bag of chips" for your music reproduction system.

KR Audio Electronics
Nadaemlejnska 1/600
180 72 Praha 9
Hloubetin 6904
Czech Republic

e-mail: kr.audio@tiscali.cz
website: www.kraudio.com
voice/fax 00420 2 66107168


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Yup, how could any review covering 300B variants be complete without the ever lovely Western Electric 300B?  Please let me say right up front that i love the midrange.   It is one of those midranges that make you want to crawl up in it and stay warm, cuddly, and happy.  Especially if you have a not so smooth digital front end, the WE300B can be just what the doctor ordered!  Alas, not all is perfect though.  The extreme uppermost and lowermost frequencies aren't quite reproduced as well as the KR Enterprise 300BXLS or even the Art Audio or JJ, but are better then the hazy Centron 300B to my ears.  
  When comparing the weight of the tube itself, the WE300B seems really lightweight when compared to the KR Enterprise tubes too.  It's an amazing weight difference!  The WE300 is very lightweight physically.  Still, the sound has all the charm you could ever ask for in the crucial midrange where a better part of the music resides.  The WE300B seems to also be the least susceptible to microphonics too!   A very quiet tube that WE300B is.  It is a classic. Sensual, ravishing, exquisite...  Well, you get the point here.  One of things i love about tubes is that i can easily turn the amplifier off, drop in a set of whichever tubes i feel will compliment the music the best, and be back up and running within minutes.   Solid-state output folks can't really do that.  Tubes rule!!!

Western Electric
1230 Peachtree Street
Suite 3750
Atlanta, GA. 30309

voice (404) 874-4400
fax (404) 874-4415

www.westernelectric.com
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