With all the upgrades, this is a very good sounding DAC. Warm and fast. Quiet background. Big soundstage, strong bass.
Regarding the upgrades: Original owner had these done:
--24/96 upgrade installed by MSB, engaged by a switch on the rear of the chassis, indicated by an LED on the front panel (cost $259)
--Channel Islands Audio analog section upgrade (cost $199), includes cap and Burr-Brown op amp upgrades.
My upgrades:
--Very, very good power supply. Oversized toroids, high quality circuit boards with audiophile-grade diodes, caps, etc. Power switch and cables are on the back of the unit. The front of the unit has one green LED to indicate that the power supply is switched on.
--Removed relay at the RCA outs and installed small wire jumpers in its place, which got the relay contacts out of the signal path. (The purpose of the relay was that, when the unit was powered off, the bypass inputs would be routed directly to the output jacks. Now the bypass inputs are disabled, and I normally keep the unit powered all the time.)
$520 shipping included.
Gallery Pics here:
http://www.audiocircle.com/index.php?action=gallery;area=browse;album=4566
