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
Hey Jab, What is "those things" and which BDR cone do you recommend #3 or #4? Regards, Brad