vmps, art d/io, & boldercables.com

Thanks for all of your advice, Doug.
I think you're right about the tube. The sound became subtly more refined and relaxed with the tube in vs without so I am leaving it in for now. I just got the Stancor ps tonite and that makes a much more noticeable improvement.
I have ferrite RFI blockers on my Ic's but will get some more for the rest of the system.
I tried going w/o the line attenuators and it did not work out. Some aspects of the sound improved, like the size of the soundstage, but the sound got a bit ragged as I could hear my input stage starting to overload on dynanmic passages-not pleasant to hear. The Stancor power supply plus burn in time has improved the soundstaging.
I have tried the Radio Shack digital cable years ago and found it was very simiar to Canare Digiflex cable; not bad, certainly worth $10.
The Apogee is only a little better. I have owned both the old and newer version of the Apogee Wyde-eye. I am currently using Harmonic Tech Copper link, which I prefer to the Apogee. I have tried Monster data link and Ensemble Digiflux with the Art DI/O and I also have a Madrigal MDC on hand (which costs more than the DIO), but until the unit burns in, I think I will go with the Harmonic Tech for now. The Stancor ps has warmed everything up a bit, so I will try all of the above mentioned cables again in a few days and will see what I can do to get rid of the RFI.

JoeB: You're leaving the tube in for D/A? The tube is for A/D only, and will just draw from the power supply. This isn't a good thing.

Doug: BTW, Thank you. I bought the Apogee cable from fullcompass.com. I'm very happy with it's full freq. extention, it's ability to resolve low level information, and found it to be a very dynamic cable (both micro and macro). I'm sure that the FIM cable is better, one of my friends has their speaker cables and interconnects. However, at less than $30, the Apogee is a steal! It smoked the Monster cable that I'd paid around 3 times as much for.

steve, there seems to be a trade-off w/the toob in the circuit - you're correct that it draws power from the p/s, but it also reduces elec'l leakage (i'm sure this isn't the correct technical term!) from the adc side into the dac. best bet is to try for yourself.. some prefer it one way, some the other. if a di/o's only mod is the upgraded p/s, & internal parts haven't been replaced, i'd be inclined to leave the tube in. if lotsa mods have been done, yank the tube...

doug s.

I found that taking tube out of the ciruit inproved both stock out of the box mode and after intesive mods. It just sounded better with the tube removed. Most that I've heard from have found the same.

I pulled the tube out when I first got the dac and out of curiousity, put it back in after a few days. I didn't notice any degradation of the sound putting the tube in, and it "seemed" a tiny bit better, nothing significant, so I have left it in for now. Could also have been my imagination, cycle of the moon, too much wine, etc. I want to try the A/D section soon, also so I will need the tube for that. The Stancor power supply made a noticeable difference, for the better. Ordered some 75 ohm video shorting plugs for it today to see if they help the RFI situation. FYI, if anyone is planning on ordering the Stancor from Allied, they have a $25 min order.