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. 





I have had several Class D amps in my system in the past 10 years, and the earlier versions of them were dry and lifeless after extended listening sessions.  In the last couple of years, I had the VTV Audio EVO 1200 Class D amp with the Purifi module, with the aftermarket ministrations of Ric Schultz, and while the sound was as Ralph describes it, there was something missing in the sound after extended listening sessions.  It may clearly be due for my inherent biases, I will readily admit that.  After listening to the VTV amp for few months, I swapped back into the rack my McCormick DNA .05 which had their Platinum upgrades and after a few minutes of listening to it, I said to myself... "Ah, what was missing with the VTV amp has all been restored."  That is what I experienced, plain as day. I later got the stellar Wells Audio Innamorata SS amp, lovely both in its looks and more importantly in its sonic excellence -- easily the best SS amp I have ever had in my system.  After a few months of enjoying the Wells amp, I swapped Don's KT88 tube amp back in the rack and it was easy to hear the difference in SQ... back was the liquid sound of tubes with amazing extension on both ends and a soundstage that mesmerized my ears.  None of the sluggishness in sound of my old CJ gear, which was appealing to my ears, but far from an accurate sound reproduction, so Don's KT88 amp had all the advantages of a SS amp but had the warmth, richness and liquid sound that I desire which serves to envelope me in the listening experience (which I agree my VTV amp did to a degree initially) but here is the difference:  after hours and hours of listening, I loved even more the sound for the KT88 amp, whereas in extended listening sessions, there was a lacuna in the sound with the VTV amp that I clearly sensed and missed.  

That said, my new 300b monos are a quantum leap forward in SQ even compared to Don's KT88 amp in all respects and most noticeably this:  it sounds as if there is no amp at all... just glorious music enveloping the room, with pure tonal and timbre correctness that astonishes me... and absolutely dead quiet.  As good as the Kootenai is, and it is a stunning and powerful 65wpc tube amp, the 300b monos are in a whole different realm. 

I have not heard the fairly-price AtmaSphere Class D mono's at any audio show, but as Ralph has come from a tube-centric point of view, I must acknowledge that he might have be on to something with his design, surely he is. There are lots of advantages to using a Class D amp and God bless those that love them.  

This erudite conversion with Lynn, Don and others has been a deep dive into tube design philosophy and I personally am hearing the splendor of their creation moment by moment, lucky me, for darn sure.  Again, and not to be disputatious on this wonderful thread, for the liquid euphonic and most natural presentation musical reproduction with my new 300b monos, I am still firmly in the tube amplification realm as it recreates music in such a realistic way, so pleasing to my ears.  The hell with the heat the 300b monos throw off!

Now, with another 100 hours on the amps, I will amplify the comments I made in my OP--- these amps are the most stunning addition to my 50 year quest for more accurate and pleasant sound in my system.

I am driving my 86db efficient CSS Audio Criton 1TD-X speakers with the 300b amps at the moment and I can play music as loud as I can possibly tolerate it with no sense of distortion or clipping.  I have a 8 wpc Willsenton 300b integrated amp which I drove the same speakers with and it got pretty distorted as I rotated the volume knob to the right.  I recall that Don said that his mono's sounds "like a 100 wpc amplifier" and he is exactly right.

Boys, you are going to have to pay to play with Don/Lynn's new monos, but it is clear to my ears that if you are looking for an end game in amplification... and have the appropriate synergy with your speakers, then I hope you get a chance to hear them, which I will in the Spatial Audio room at the Pacific Audio Fest this month in Seattle, along with Don's new companion tube preamp.  

I have a pair of Cube Audio Jazzon single-driver speakers arriving on Monday which I think will be a stellar match for the 300b monos, but still the the mono's have made my Spatial Audio Triode Masters sound the best they have ever sounded, by far.  To be candid, if I had had the new 300b monos, driving my Triode Masters, before I ordered the Cube Audio speakers, I don't think I would have ordered them so as the Triode Masters sound so fantastic.  Don Sachs encouraged me to buy them ~6 years ago and now he has as his reference speakers the Spatial X- speakers, clearly an upgrade from my Triode Masters.

I live in Sacramento and would be happy to invite music lovers to come and hear my Don Sachs gear and my Cube Audio speakers.  Send me a private message and let's hear them together.    Cheers!



Now, with another 100 hours on the amps, I will amplify the comments I made in my OP--- these amps are the most stunning addition to my 50 year quest for more accurate and pleasant sound in my system

I believe you. These amplifiers with your Cube Audio Jazzon is going to be a sublime pairing.



As a 300b amp owner yourself,  you know whereof I speak.  Expect a report back on this thread in due time when the Cube speakers are run in.  Some folks agree that Cube's driver technology is one of the biggest leaps forward in speaker design in a long time.  I heard them at Axpona and was compelled to have them in my system.  


A friend has owned the Cube Audio Nenuphars for over 4 years and simply loves them. They’ve taken full range single driver speakers to a very high standard of performance.


At the expense of a small technical quibble, I don’t see Class D as entirely analog. Without the pulse-width modulator, it is a 100~500 kHz AM transmitter that transmits a silent carrier. The pulse-width modulator is what makes the whole thing possible ... the pulse widths are precisely (and I mean very precisely, down to parts per million) 50% positive and 50% negative, if the input is zero.

Deviations from exactly 50/50 alter the pulse widths (to 51%/49% or any other ratio) but the pulses themselves are rail-to-rail, and the output devices are purely switches. It is a modulation system like AM or FM, which are also analog, but it is a modulation system nonetheless. Without the PWM modulator, there is no signal that can get through the amplifier.

Class D has been around commercially since the early Seventies. The trick is extremely fast switching with no overhang, resistance to load reactance, and a (very) low-distortion modulator. An FM transmission chain that achieves less than 0.1% distortion is at the limit of the art, and PWM modulators inevitably have their own set of distortions. PWM is not inherently distortionless, any more than AM or FM. Yes, it can be transmitted, but it would be very sensitive to multipath and group-delay errors ... both would cause distortion. With both FM and PWM, small time errors translate into amplitude distortion after demodulation.

Interestingly, SACD/DSD, at the native 2.8 MHz switching rate, is a type of quantized PWM. Since the pulses of true PWM are variable width, they cannot be recorded on digital media. DSD uses dither encoding and digital feedback (noise shaping) to quantize the PWM pulse train into fixed widths and provide the closest approximation to true PWM on playback.