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Reviewer:
Srajan Ebaen
Financial Interests: click here
Source: iPod Classic 160GB, Cambridge Audio iD100, Aura Vita as CDP or DAC
Integrated amplifier: Aura Vivid
Headphones: ALO Audio-rewired Beyerdynamic T1, T5p, Sennheiser HD800, AKG K-702, Audez'e LCD2; HifiMan HE-500, HE6
Cables: Complete loom of Zu Audio Event
Powerline conditioning:
Furutech RTP-6
Sundry accessories: Extensive use of Acoustic System Resonators, noise filters and phase inverters
Room size: 5m x 11.5m W x D, 2.6m ceiling with exposed wooden cross beams every 60cm, plaster over brick walls, suspended wood floor with Tatami-type throw rugs. The listening space opens into the second storey via a staircase and the kitchen/dining room are behind the main listening chair. The latter is thus positioned in the middle of this open floor plan without the usual nearby back wall.
Review component retail: This was a Kickstarter project for both DIY and assembled units based on unnaturally low pricing to attract sufficient original contributors to raise funding. Should the project/company get formally established past fulfilling all KickStarter orders, common sense predicts that pricing will have to increase significantly to be commercially viable. What that pricing might be was unknown at publication date.


You've got a matured audio circuit ready to go commercial
. The enclosure design is in the can too. What ought to be the next steps? This email exchange suggested a potentially new approach and also is how I learnt about it: "Hello Srajan, I got your name from Tyll Hertsens who has been listening to a headphone amplifier I have been working on and am launching on Kickstarter. He suggested you might be interested in listening to it as well. I would be delighted if this were true. The amplifier is a Zen-style class A amp sporting a new Silicon Carbide JFET from SemiSouth. The goal has been to make an amplifier that sounds terrific in terms of clarity and offer it constructed with both cost and quality in mind for a competitive price. Of course we are trying the Kickstarter route to raise capital for launching an updated version at a more realistic market price later and are simply capitalizing on economies of scale and getting the name out. Here is a link to the Kickstarter page. It will likely launch on or about this coming Wednesday (September 29th). Presently Tyll and Steve Guttenberg have the only two amplifiers available. If you're interested I will figure out how to get one over to you. Looking forward to hearing from you." - Colin Shaw


Having slightly earlier reviewed the Warpspeed Octocoupler passive preamp, I wasn't averse to tapping into the broader grey zone of DIY-gone-pro—everyone has to start somewhere—but in this instance did spot what appeared to be obvious issues preventing a review assignment at this stage. "Hello Colin, thanks for the note. I wasn't aware of the Kickstarter platform but I think I understand the concept. I also appreciate how/that a review can generate interest to help launch a project. However until now the role of the audio press has been to report on already existing products, i.e. stuff that's in formal production ready to ship and sell for a given price. For new makers it's admittedly a chicken/egg thing but that's how it's been. What you seem to be asking is to use the press before the product is really in production. A review then becomes instrumental in getting a project from pre-production to formal production status. Because I assume when you say "listening to it", you're really asking for a review. After all, I don't do product consulting or give feedback on pre-production gear. This I would need to give some thought. In some ways it's putting the cart before the horse. That brings with it a number of issues. If you have any additional information to throw into the pot, let's have it -:)"


"Hello Srajan, it does seem a somewhat foggy area where the product is currently positioned. You are definitely right, it is not in actual production at the moment. We are excited about giving the Kickstarter idea a try for raising capital for pushing it further. I suppose the benefit is that the product—if the Kickstarter idea is successful—actually reaches people and gets out there for an attractive price. That said, reaching out has more to do with alerting you that it may be something to watch more than a request for a traditional review. The cart/horse issue seems to be true for everyone and I completely understand if we need to wait to see what happens with the Kickstarter strategy or if we need to raise capital and launch by different means on our end. I suppose the thing to do is to let you cogitate on it." - Colin


"Colin, another question I had for you was the 'Zen-style' bit (which in this context suggests Nelson Pass) and the SiC part. Does this mean a Pass-based circuit? If so, is it openly credited as such and has it been approved by Nelson for commercial use?" "That's a good question. It's an area where I'm not quite sure on the socially correct position. Nelson Pass certainly has pretty much brought the simple constant current-driven topology to near legendary status. This I perceive to be from an interest in optimizing a simple topology and showcasing specific gain transistors. The flip side of course is that it's an ancient topology as old as the long-tailed pair and the common-source configuration which were pretty much forgotten as power output became a driving interest. For obvious reasons there is no trampling on my part on that very clever idea Mr. Pass had with the Aleph in such circuits. I would like to think that I am somewhat clever as well. I have a patent app submitted with respect to this topology though it's not relevant to this headphone amplifier."