Video Asylum

Posted by Miguel Avila on October 12, 1999 at 15:23:17:

In Reply to: Re: Enlightened Audio Designs OVATION Preamplifier (HT) posted by Chris W on October 06, 1999 at 11:33:26:

Hello Chris,

Sorry for the delay, didn’t check this web page for awhile.

With the Theater Master Ovation, differential or balanced mode is only possible in Stereo playback. The reason for this is that the number of DAC chips, digital filters and current-to-voltage stages are limited to six (there are actually three stereo PDM-100 digital filters)

In balanced operation, two DAC’s are dedicated for each stereo channel. In this mode, separate DAC’s are needed for the balanced outputs’ positive and negative polarities, so a total of four DAC’s (five if you are crossing over the main channels to the subwoofer) are necessary during Stereo playback. Because the Ovation has six PCM 1702 DAC’s, balanced operation is not possible during matrix or other surround modes. In this case, each surround channel requires its own DAC, and the balanced interface’s negative terminal is grounded rather than driven.

This design choice allows EAD to bring the refinement of balanced topology for dedicated stereophonic playback at a reasonable price. For instance, if EAD decided to implement balanced operation in surround mode, at least two additional DAC’s would be necessary (just to keep the front channels in balanced mode), adding to the cost. For six balanced outputs twelve DAC’s would be mandatory and component count would almost double, as well as price. Other manufacturers offer balanced outputs in surround mode, but with downgraded DAC’s and general circuit design because otherwise, price wouldn’t be competitive. Definitively what they make up adding balanced outputs is overshadowed by the lower quality components they are obligated to use.

In my view, balanced topology is best suited to get the most from CD playback. For movies, I think the difference between single ended and balanced connections reduces to nothing. What really counts is the general quality of the DAC board.

The upgrade from Encore to Ovation not only brigs you the balanced outputs. The Ovation includes multibit ladder DAC’s, Acculinear C-to-V stage and the Digital Flywheel reclocking circuit.

I have auditioned the Encore and find it to have excellent performance to begin with, better than many sub 6K processors. But the Ovation reminds me more of tube electronics, the sound has a more liquid texture and the soudstage is slightly more three dimensional. I think the Acculinear circuit is most responsible for this. Also, the jitter reducer masks the differences between whichever transport or digital interconnect you may use. Actually I can hear an improvement when switching ON my unit’s Flywheel Option (better extension and detail). Fortunately, I have yet to see the unlock problems other owners have experienced with DVD’s. (My source is a Sony DVP-S7700).

I recommend you to arrange with your dealer an in home trial. This would allow you to make a direct comparison between the two processors using your existing components. I think you won’t find a better way to judge if the $1600 upgrade is worthwhile. You could also wait and save the cash for the promised DVD Audio upgrade.

Glad to share these thoughts with you.
Don’t hesitate to contact me if you have any comments.

Best Regards,

Miguel Avila.