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New Rowland Criterion 2-chassis battery pre

Jeff Rowland Design has just created a page for its upcoming statement-level, twin chassis, battery powered full function preamplifier. Detail is still scant, but a little bit of info is already available, in addition to front and rear view pics. Here’s the page:
http://jeffrowland.com/Criterion.htm
And here’s the front view:
http://jeffrowland.com/Criterion-front.htm
And here’s the rear view:
http://jeffrowland.com/Criterion-back.htm

You will find a few specs already on the site. JRDG should be publishing more info in the next few weeks. I will post here as I receive it. in addition to the published specs that you can read on the page above, here are a very few additional tidbits that I have learned this far:

. Uses Burr Brown TI OPA1632 high speed fully differentially balanced modules.
. Includes phono stage.
. Uses standard NiMH D-cell batteries available in most electronics stores, loaded in 2 rear-inserted tubes of power supply chassis.
. Capable of AC/DC operation . . . will recharge batteries on independent circuit during AC operation.
. Full remote control
. Target price $18K (not sure yet)
. Availability: probably early Fall 2008.
. Will be featured at RMAF in Soundings Hifi suite Marriott 503 or 505 from Oct 10th to 12th in Denver.

And sorry folks, I have not heard this device yet. Nor I have any good third party reports on its sound. Any speculations on Sonics from my part would be just. . . pure speculations. I’ll keep everyone posted as I learn more.

Guido
guidocorona
guidocorona OP
4,298 posts
 
Getting back to topic. . . it's time for a brief update at approx the 55 hours mark.

Most of the day I have been playing from a CD of Dvorak violin/cello/piano trios from a set of complete Dvorak chamber works on the Brillian Classics label. This morning at about 42 hrs there was a definite steely whine on the violin, a general hardness superimposed on rather good harmonic development and quick transients. There was some sense of the acoustics of the venue, but it was partially hidden by some generalized glare. By tonight a much more natural and comfortable violin was starting to emerge, and I seemed to be hearing more and more into the venue. The sign that things are going in the right direction is that while this morning I had to keep the gain rather low, by tonight I was raising it considerably and enjoying the result. . . . and sinking into the listening couch.

Long way to go I suspect, but what's interesting is that I am not hearing a lot of abrupt fluctuations in sonic quality, but rather a slow relaxing and opening up of the sound.

We'll see what happens overnight. I'll leave Criterion playing from my old NAD tuner at low volume.

G.
jimjoyce25
215 posts
 
I'm curious: What is the interconnect between the battery/power supply chassis and the preamp itself? What kind of wire? What kind of terminations does it have?
guidocorona OP
4,298 posts
 
Jimjoyce25, there are 2 12inch pigtails connecting the control chassis with the audio chassis. One connects data buss and DC power to the right channel, the other one is the same for the left channel. The cables are custom cables with small round custom connectors. G.
jimjoyce25
215 posts
 
If you have other cables that will carry the DC power, it would be interesting to know if changing the power cable makes a difference in the sound. In my experience it does.
guidocorona OP
4,298 posts
 
Jimjoyce25, I have no doubt that a different power&data pigtail may affect sound one way or an other. There are however 2 things to bear in mind:

1. Experimenting with wires of any kind prior to complete break in is futile. . . you would be shooting at a moving target. . . what works today is likely to be an overcompensation after just a couple of weeks.

2. The pigtails are not simple 3-wire jobbies. They are multiwire bundles that carry power as well as a complete digital control buss.

In some future, if the spec is ever made available, it would certainly be interesting to have some of our favorite OEM cable manufacturer create custom interchassis pigtails for Criterion. . . won't be inexpensive I fear.

G.
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