As a continuation of my fine-tuning process,  I'm selling three pairs of 12... tubes I no longer need in my system.  My source and hybrid integrated amplifier I've settled with use 12AX7 Tubes, and I originally bought a bevy of different 12AX7 tubes.  Since I don't require the gain,  I settled on the 5751 tube and sold the 12AX7s here (Thanks!)  But, during my experimentation phase I acquired other lower gain tubes in the same family, which are for sale now for your rolling pleasure!:

All purchased from Upscale Audio and Platinum matched
-1 matched pair Mullard CV4003 (12AU7) purchased several years ago, 500-1000 hours.  $60.00 with shipping
-1 matched pair Mullard CV4024/12AT7 (cryo'd) purchased about 6 months ago, 200-300 hours. $75.00 including shipping
-1 matched pair CIFTE 12AU7 (cryo) about 3 month ago....less than 200 hours. $75.00 including shipping

Feel free to view the tube reviews on Upscale's site.  I found them to be spot on, particularly those regarding the CIFTE (holographic!!!)
I wish I could keep them all, but found my equipment, to me, sounds best closest to the designed gain.  5751's are the happy spot for me!  I've heard the 12AU7 and CV4024/12AT7 tubes in equipment designed around these lower gain tube, as well as my own equipment, and the richness is stunning!! I venture to say these tubes in a system with silver or silver-plated ICs, power cords, and/or speaker cables will be the business!! The CIFTE is not as rich as the Mullards, but significantly more spacious.
Buy them all and mix and match!!

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