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

Stereophile published an article on the Westinghouse 300B, which, unlike cheap modern 300B triodes, had a triple coated cathode which lasted longer and was the secret to the better sound. If you can tolerate less power the NOS 45 globe tubes were made the same way and many people find them richer sounding than the cheap modern 300B. 

Around 2005 there was a Japanese 833A SET amplifier driven by 300B transformer coupled to the grid of the 833A and rumor had it the 833A was run on only 1000 Volts with a positive grid bias to force it to draw more plate current. It sold for $350,000, but the parts and labor could scarcely cost a percent or two to manufacture it. You would not need high sensitivity speakers for it, you can use planar magnetic speakers if you want. Lundahl has probably the best coupling transformer there is for coupling a globe 45 to the 833A grid which can run on zero or ground bias for eliminating a bias supply capacitor from the signal path and this is more than enough power for driving less sensitive speakers. Either a globe 45 or a WE 300B will work for this. Hammond makes a more robust air-gapped output transformer rated at higher DC current than smaller more expensive big-name brands and it is perfect for the 833A. 

This is relatively easy to build yourself for less than $2000 retail in parts if you know how to be careful with the 1000 Volt power supplies it needs. 

45 is indeed very very nice sounding.

Cost has gone up quite a bit though. $2k will be barely enough these days for a high quality 45SET DIY project, assuming no fancy enclosures and not using big name irons like ISO or Hashimoto.

 

 

 

 

 

 

 

 

 

 

 

Not going anywhere near an 833 or those Eimac transmitter tubes. No thank you. Those things light up a room with a dazzling white light and get serious, room-heater hot. They are designed for transmitter use, with forced-air cooling that ducts to the outside.

And if somebody chooses speakers that are 0.2% efficient, well, what did you expect? Class D or Class AB for you, as well as a dedicated AC power outlet that goes straight to the circuit-breaker box.