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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
 
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.
jimjoyce25
215 posts
 
Yes, no question that any comparison should wait until break-in is complete.

I guess the question is whether the power supply and digital portions of the cable are separable (ie, whether they share the same input on the preamp or separate ones).
guidocorona OP
4,298 posts
 
Thank you Jimjoyce25, what I have found out is that switch mode power supply, DC power supply, and microcontroller logic are each segragated in their own pockets milled in the control chassis. Furthermore, the data buss is kept off line until the user issues a command of any kind from the front panel or the remote control. At that point the microcontroller and the buss come online, the requested command/change is performed, then the buss goes back to sleep and is taken offline. Furthermore, when the DC power supply is active, the AC power supply is also taken offline.
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