2. amps-preamps
  3. 1216693488

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, 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.
guidocorona OP
4,298 posts
 
At approximately 126 hours into the break in process it is worth while that I post a brief update.

The sound of Criterion continued to open up and to relax until about 85 hours of playing time. . . I was starting to hear a considerable amount of ambient cues. Without the sound ever venturing far towards the warm sound of neutral, performances were becoming more and more textured and emotional. I was very pleased by the amound of harmonic content, macro and micro dynamics, and immunity from distortion in loud passages.

At approx the 90 hour mark, sound turned markedly toward surfacy, pinched, harsh, and brittle. . . Violins became steely and whyny, piano steely and shallow. . . detail gone out the window. . . ambient cues no where in sight, micro dynamics an alien concept. Seems Criterion is not at all immune from the dreaded break-in doldrums. This morning, at approx 115 hours, the creature was definitely still in a bad mood.

Sometimes in the late afternoon things started to open up once again. Now, at about 126 hours, the sound has reopened up considerably, if not to the point where it was a couple of days ago. . . music is becoming enjoyable once again. Can't help being anxious. . . patience is a lot easier to preach than to practice.

G.
pinkus
144 posts
 
Guido, don't be anxious. These stories always have a very predictable ending. My prediction is that you will love the Criterion above all others, and it will be your new reference. It will allow you to hear things from your recordings that you have never heard before. You will create an emotional connection with music like never before.

Have I listened to the Criterion you might ask. Nope, never. Don't have to, to know how this movie ends :-)

Enjoy and cheers !
More to discover