November 25th 2014

It has been some time since my last posting back in July, and what a time it has been. Allnic and Hammertone have been busy with the release of the D-5000 DHT DAC, coordinating dealer participation in a number of shows, and working on several very exciting new projects. I intend to let you know more about the new projects in my next post, which will be in just a week or so - for sure! This time, I just want to talk about the D-5000 DHT DAC, to which the response has been overwhelmingly enthusiastic, and terrifically gratifying for all of us involved in its design and release: KS Park at Allnic, Colin Shin at Waversa and me, here at Hammertone Audio.

The positive feedback on Allnic’s first digital product from customers and reviewers continues to come in. Noteworthy today is the review by Art Dudley and the accompanying measurements by John Atkinson of Stereophile in the December issue. While Mr. Dudley was positive in his views on build and performance, admittedly while questioning the value of up-sampling (something we all know many audiophiles are rather ambivalent about), Mr. Atkinson’s test results were very poor.

The measurement results Mr. Atkinson obtained shocked him - and us!! He wondered if the results were due somehow to something that happened to the unit in transport to him from Mr. Dudley’s residence, since the listening results did not square up at all with his test results. We wondered the same thing, not only for that reason but also because Mr. Atkinson’s results absolutely did not align with our own, not only of that particular unit but of every D-5000 Allnic has produced.

However, we weren’t able to provide a reply to the magazine by its deadline for submission for its Manufacturer’s Comments section. That was because we had no way to look at the unit until it was returned to Korea and, collectively, we felt it inappropriate just to speculate, especially since there was such a major divergence from our own measuring results.

When KS Park and C. Shin received the review unit, they found that three of its four 3A5 NOS DHT tubes were bad. These tubes, like all DHTs, are inherently delicate, and the 3A5s are more than half a century old. They can indeed be damaged by rough handling in shipping, and otherwise! Having both analog output tubes in one channel and one tube in the other go bad could certainly be one cause of the issues Mr. Atkinson’s measurements revealed, including of the differences between channels that he reported.

Further testing in Korea has confirmed that no D-5000 with tubes intact measures like the unit Mr. Atkinson received. See the graph in this post that KS and Colin provided for one randomly selected new unit.

Every Allnic unit, including all its tubes prior to installation and after, is thoroughly tested and burned-in for days before shipment. We have a very high degree of confidence that all tubes are performing to specification and within design parameters when they leave the factory. However, one can never accurately predict absolutely the sort of treatment units will receive in transit, nor the real lifespan of any tube, let alone 50 year old and delicate DHTs!

Fortunately, we have thousands of 3A5 tubes and will be able to provide replacements, at no cost to the user, for any units where, unfortunately, some factor has caused a tube or tubes to fail. In addition, Allnic has set up a new facility for more rigorous test and burn-in of several types of NOS tubes used in Allnic gear - including the 3A5 – even though the problem in the case of the Stereophile review unit was, in our view, likely due to shipping issues.

We will be approaching Stereophile to see if we can interest them in doing a follow-up of the measurement test with a new D-5000 and, preferably, also of the listening test. Failing that, we will see if the magazine will agree to publish a comment from the manufacturer where we can provide our findings. We’ll let you know how that goes.

In the interim, we are confident, along with the rapidly growing number of exceptionally happy purchasers, that the D-5000 may be unrivalled in sonics and is one of the most flexible DACs on the market – at any price!! Please enjoy any holidays you have upcoming, and may you always be able to revel in your music!