I used to have the CJ premier 14 pre amp and it too uses the 6gk5. For the premier 14 I prefer the mullard 6gk5. Sylvania was noisy and the GE was too rich in the mid range for my taste. mullard has lots of air, details and very transparent. I do have a pair of mullard 6gk5 and a pair of sylvania 6gk5 that I no longer need. Send me your address and I will send them to you (free). If you like them, keep them. If you don't, then pass them on to the next person who needs them. They tested good in tube tester.
c-j Premier 9 DAC and 6GK5's tubes.
c-j Premier 9 DAC uses a pair of 6GK5, apparently preffered by the manufacturer, as it has been used in many of their amps and preamps. As the tubes are overdue ( after 3 years ) and I'm looking for replacements, I'm wondering if somebody out there could advice me on: going for the original Sylvania tubes or... GE, Telefunken, RCA, russian, chinese, chech... I would also apreciate opinions from present or former owners of this DAC.I use c-j DR1 transport and the DAC feeds directly into a pair of Bryston 7B-st monos. The speakers are Apogee Scintillas, by amped by Symo cables. Power conditioners are Chang 3200 and power cords are XLO's Pro's.