It is a Scully lathe equipped with a Westerex 3D cutter head. We went with the Westerex 3D as it is an easy load for a tube amplifier, just the thing for what we had in mind! This is the first LP cutting system known to use on OTL as a mastering amplifier, in this case a modified Atma-Sphere M-60 Mk3.1. We are working on initial releases already- there is a lot of interest in vinyl…

If all goes well, we will be unveiling a new amplifier at the show, a model not seen before

About the only way we have found that works is to use a mechanical system to advance the control. We use a custom-built switch for the volume controls in our preamps, as that has proven over the years to be the best volume control setup (remote or not) available. We did not want to back away from that performance in order to offer a remote. So our systems use a motor to advance the volume control switch, using the same style of switch that we have always used.

Older preamps can be optioned with the control, which was also one of our goals.

“How can an amplifier that performs so poorly by every ‘objective’ measure produce such an involving musical experience?” He concludes this paragraph after asking some similar questions (rhetorically), that “As of yet, no one has the answers to these questions.”

I found myself startled to see a statement like that in print. We have known the answers to those questions for some time (‘we’ meaning Atma-Sphere, but in a larger context a good number of other designers as well, particularly those that design SET amplifiers, not that that should be any great surprise), and by ‘some time’ I mean well over 20 years in our own case.

Its all about the rules of human hearing. Unfortunately, the audio industry has been for the most part ignoring the research into human perception over the last 4 or 5 decades. This has resulted in a schism in the high end industry, as there are those who *do* pay such attention, while most of the industry is asleep at the wheel. The portion that has been asleep at the wheel is the vast majority of the industry, and if anyone wonders why the industry has been shrinking over the last 10 years (it has), this is one of the reasons why- the sound of equipment must reflect the rules of human hearing in order to remain relevant and inspire people with the possibility of music!

This schism has resulted in the debate of tubes vs transistors, the need to match amplifiers to speakers, and the well-known objectivist vs subjectivist debate. One need not look very far to see these debates roiling about on the audio forums, which they have since the beginning of the Internet (well before the the www).

So- the answer to Robert’s questions (and to his credit, I appreciate that he put the word ‘objective’ in quotes, which is where that word, for the time being, belongs): The simple truth is that the ‘objective’ measurements do not measure the right things (and are thus not really ‘objective’, they are instead arbitrary for the sole purpose of looking ‘good’ on paper, sort of like the Emperor’s New Clothes). For example, our ears are tuned to use the odd ordered harmonics of any sound as a means to determine the loudness or volume of that sound. When an amplifier distorts these harmonics even by trace amounts, we hear it easily, as an artificial increase in the apparent volume and also as a brightness (you might say that our ability to discern the volume of a sound is one of the more fundamental rules of human hearing). Yet the ‘objective’ measurements look for the lowest THD, and in order to achieve such numbers, many designers will use techniques that actually *increase* these odd orders, while decreasing overall THD (this causes such an amplifier to be violating this fundamental hearing rule). This results in an a-musical amplifier, while an SET, with poor measurements, might sound very nice indeed.

SETs (and also our own amplifiers) lack these trace amounts of odd ordered harmonics where most transistor amps and push-pull tube amps tend to have larger amounts- in fact more so at lower power levels (that ’1st watt’ phenomena). SETs and our amps have lower and lower distortion as the power is decreased.

Our amps differ from SETs because when power is increased significantly, say over 1/3 full power, there is no serious increase in odd ordered harmonic content with our amps, which is why they are relaxed at high volume. SETs engage these harmonics at higher power levels, and since these power levels are mostly having to do with transients, this causes SETs to *seem* far more dynamic in a way that belies their lower power capabilities (since the exaggerated loudness cues then exist only on the transients). Its a psycho-acoustic phenomena.

You can contact us for more information about this and other phenomena. You might also read our paper regarding Paradigms in Amplifier Design. What I have mentioned here is the tip of the iceberg

Stay tuned for more of the same from us in the near future.