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
128x128bradz
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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............
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