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300b lovers

I have been an owner of Don Sachs gear since he began, and he modified all my HK Citation gear before he came out with his own creations.  I bought a Willsenton 300b integrated amp and was smitten with the sound of it, inexpensive as it is.  Don told me that he was designing a 300b amp with the legendary Lynn Olson and lo and behold, I got one of his early pair of pre-production mono-blocks recently, driving Spatial Audio M5 Triode Masters.  

Now with a week on the amp, I am eager to say that these 300b amps are simply sensational, creating a sound that brings the musicians right into my listening room with a palpable presence.  They create the most open vidid presentation to the music -- they are neither warm nor cool, just uncannily true to the source of the music.  They replace his excellent Kootai KT88 which I was dubious about being bettered by anything, but these amps are just outstanding.  Don is nearing production of a successor to his highly regard DS2 preamp, which also will have a  unique circuitry to mate with his 300b monos via XLR connections.  Don explained the sonic benefits of this design and it went over my head, but clearly these designs are well though out.. my ears confirm it. 

I have been an audiophile for nearly 50 years having had a boatload of electronics during that time, but I personally have never heard such a realistic presentation to my music as I am hearing with these 300b monos in my system.  300b tubes lend themselves to realistic music reproduction as my Willsenton 300b integrated amps informed me, but Don's 300b amps are in a entirely different realm.  Of course, 300b amps favor efficient speakers so carefully component matching is paramount.

Don is working out a business arrangement to have his electronics built by an American audio firm so they will soon be more widely available to the public.  Don will be attending the Seattle Audio Show in June in the Spatial Audio room where the speakers will be driven by his 300b monos and his preamp, with digital conversion with the outstanding Lampizator Pacific tube DAC.  I will be there to hear what I expect to be an outstanding sonic presentation.  

To allay any questions about the cost of Don's 300b mono, I do not have an answer. 

 

 

whitestix
atmasphere's avatar
atmasphere
11,960 posts
 

@alexberger Since an SET is a constant current load insofar as the power supply is concerned, it won't make much difference if you use tube or solid state rectification. But you might want to consider what happens when the AC line voltage changes. The filament of a tube rectifier cools off when the AC line goes down- so the B+ voltage drops more than one might expect since the rectifier gets less efficient. . Plus you'll find that they each have a 'sound'. If you set up HEXFRED rectifiers properly they are about as neutral as it gets.

FWIW we run a separate power transformer for the driver section in our OTLs. We did this so as to prevent any modulation in the output section power supply from affecting the driver. This reduces IMD. Our OTLs run class A2 and have dual output section power supplies so modulation of the supply could be a concern.

In an SET a separate power transformer for the driver isn't going to have the same effect since the power supply for the B+ should be nice and quiet anyway. The separate transformer would be useful if you planned to direct couple to the power tube with a cathode follower though.

larryi
4,109 posts
 

For someone looking for an entry point to 300b single-ended sound, the Elekit is a good way to go.  I liked what I heard at a show.  Equally important is how helpful and frank and honest Victor Kong (VK Music)  sounded when one talked to him.  He did not exaggerate what the gear can do and shared information on limitations, design compromises and the like.  I have more confidence in gear when I know that the person behind it is trustworthy.

donsachs's avatar
donsachs
299 posts
 

Rolling your own is always cheaper and can be fun!  I would highly recommend that people build good quality kits if they can do so.  It is a great way to start.

lynn_olson's avatar
lynn_olson
361 posts
 

I second what Don just said. Building a kit is far more rewarding than messing around with cables or component-swapping. You get to hear for yourself what XYZ capacitor sounds like, instead of reading random comments on the Internet. I can’t emphasize enough you just can’t trust what people say on the Internet ... but you can trust your own perceptions, first, last, and always.

It’s super educational, and focuses your attention on tuning the power amp, which is where it should be. Likewise, if you build your own speakers, you get to tune your own crossover. This is where the big payoff is, and it trains your ear in what to listen for.

Amp and speaker tuning set the sound of your system. Find out how to do that, and you are most of the way home.

alexberger
935 posts
 

Here is Eleckt schematics:

http://4tubes.com/2-SCHEMATICS/BY-BRAND/ELEKIT/TU-8600/TU-8600R-Amplifier-300B-Schematic.jpg

Global negative feedback, parallel 12au7 driver, 12ax7 input, semiconductor bias control and power supply stabilizers.

chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/http://4tubes.com/2-SCHEMATICS/BY-BRAND/ELEKIT/TU-8600/TU-8600R-Amplifier-300B-leaflet.pdf

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