Looks like this finally may be ramping up for production so I figured I'd include some info on it here, all ripped from Steve's site/faceboook.
This looks to be a production quality shot of the new amp/power supply:
The transformers have octal bases and are removable, (presumably to have multiple options for different sound? Could rolling transformers become the new nervosa?) and look beautifully custom:
Steve has seemed incredibly OCD about every aspect of this build, with posts about knobs, engraved serial plates, switches and lights... both the look of the amp and the anal attention to little cosmetic touches will remind some here of Joel Marshall of Moth fame.
As for the innards, here's what Steve has to say about his design (a while ago, so maybe something has changed...)
"So, about that headphone amplifier...
When it comes to signal amplification, between tubes and transistors, I tend to prefer tubes. However some years ago (I guess it's been about a dozen or so by now), I found that I preferred something more than tubes. A technology that actually pre-dates tubes; transformers.
When most people think about transformers, they usually think power supplies or perhaps the outputs of tube amplifiers. But transformers are also capable of signal amplification. A well designed and well made step-up transformer can amplify a signal with vanishingly low noise and distortion as well as offering other benefits that active circuits simply cannot offer such as ground isolation between components.
Using transformers for signal amplification is hardly unknown. In audio they have been used for stepping up the voltage of low output moving coil phono cartridges, and in the studio are commonly found in some of the finest microphone preamplifiers.
The EMAC 515SE headphone amplifier utilizes a very high quality 1:5 step-up transformer to provide all of its signal amplification passively, eliminating power supply issues at the most critical stage of any amplifier.
And even though the 515SE uses RCA inputs, the transformer primaries are inherently balanced and provide outstanding common-mode noise rejection even when fed from unbalanced sources.
However being a passive device, a transformer cannot provide any more power out than is put into it. So in order for the amplifier to provide power amplification, active devices must be used.
In this case, the 515SE utilizes a single-ended, single-supply unity gain output stage made up of a pair of JFET and bipolar transistors configured as a Darlington pair (or FETlington if you will). After experimenting with numerous output stage configurations, we found the FETlington circuit to provide the best match for the transformers.
For signal attenuation, the 515SE uses a precision 40 step attenuator for unmatched balance at all levels (channel imbalance, particularly at lower levels, often plagues designs using continuous rotation potentiometers).
The 515SE also includes switched, transformer-coupled preamplifier outputs allowing it to be the heart of a high quality headphone/loudspeaker system. The switching is handled by the headphone jack itself using high quality welded crossbar palladium switch contacts.
Power is provided by a separate discrete, zero feedback series regulated power supply."
In the past, inevitable comparisons were made between the 515SE and Black Diamond due to the usage of transformage. That would certainly be an interesting test, but from the looks of it this amp is so artistically unique in the current amplifier landscape that its merits really des
erve to be judged on their own. This really seems like a passion project, as with price estimates of $3500, many headphone junkies will be priced out off the bat. It's still really cool that Steve and Co. want to dip their toes in these waters. I believe Steve used to be involved with Coda and this seems like striking out in a totally different direction.
Oh. The kicker on this site, how does it sound? No idea, hope they'll bring it to a meet sometime so someone here can get a lead on that.
