What tube for a Sigma dac?

Looking for suggestions on which tube to use in my Sigma 24/96 dac. My system:Sony 7700 dvd, CAL Sigma 24/96 dac, Morrison pre, Odyssey amp, and Magnepan mmg's. Someone mentioned a Raytheon nos 5751 or a Mullard nos 12ax7. Current tube is a Ruby 12ax7. Regards, Brad
Telefunken 12AX7
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Any DAC with a tube is junk. Get real for Gods sake! Tubes in a DAC! All any tube can be in the 21 century is a distortion valve. Change ur tube and change ur distortion! What a life............
Yeah, that Sonic Frontiers Processor 3 - real junk . . .
Hey Jazzcatlewis, I found that my CAL brought some "life" to my system. What kind of equipment do you use? I'm seeking opinions and not bashing. Regards, Brad
Hey Jab, What is "those things" and which BDR cone do you recommend #3 or #4? Regards, Brad
I tried a Mullard CV 4004 for a while and then switched to a Brimar. Both came from Kevin at Upscale. I liked the Brimar better but ended up switching back to my older 16 bit CAL Sigma for personal reasons. Even though the 24 bit Sigma II was much more open and detailed sounding, i really prefered the much warmer sound of the original design. Stictly a "personal taste" and "system" issue as i know others that think that the earlier version is WAY dark sounding. While i've got an EVS Millenium II on order, i've got another CAL Alpha coming in next week to hold me over. I'd still like to find another killer deal on an ARC DAC 3. As to the "member" that thought tubes in a DAC were ridiculous, all i can say is, YOUR LOSS. You've NEVER heard "music" come from a CD until you've heard a good tube based digital system. You might have heard a lot of "detailed sound" come from a CD, but never "music". I didn't believe it either, but first hand experience taught the "science" and "common sense" in me a lesson on this one. Open your ears to a whole new world and enjoy your system instead of analyzing it. Sean
Hey Bradz, I'm using the #3 Black Diamond Racing Cones [BDR] under my CD player and have noticed a warming of overall tone. The #4s are for a more neutral sound. BDR even recommends mixing the #3 and #4 cones in different combinations until you find something that works for you. I hope that helps.
Get the low noise 12AX7 tube directly from CAL. Costs about $35.00, but by far the best option IMHO. The other thing that helps with those is to upgrade all of the connectors from the crappy board mount style to the thru the bulkhead types. CAL has the connectors available for $60 for all 3. Did this to a unit I own and the changes were simply astounding. Takes about 2 hours, but if you are capable, the change is well worth the cost. I have been through tubes from Kevin @ Upscale, the 12AX7LPS, NOS.... I have spent more on experimentation than I did on the original hardware, but the stock CAL Low Noise tube is best (IMHO).