We chose the CV4024 after extensive listening tests. After numerous tests over several days, the CV4024 was the best sounding tube we tested. I haven't tried any of the cryogenically treated tubes, but I am sure someone will eventually.
The transformer is the most significant contributing factor in the change of frequency response in the V69XM, however, the circuitry is not identical to the V69M either. It is a new and different mic. Forgive me if I do not go into the technical intricacies of the mic designs, but I am a recording engineer, not an electronic engineer. Some things are best left to those who know what they are talking about. I merely know enough to get myself in trouble!
