I have now lived with these amps for some 6 months.
I choose them on Isreal Blume's recommendation over the ASL 1009's. I did not disaggree with his recommendation because the amp does sound great. My initial feeling was that they only sounded pretty good out of the box, they did lack that overall 300b lush sound, but this is easily remedied and they are easily made better. This initial sound is not bad, very controled at the extremes. This is probably what Izzy wanted. Too lush an amp may not have been his ultimate desire. It was more important to have control at the extremes AND have that beautiful mid area.
I have since upgraded to the Sophia 300b tube, NOS Mullard 5ar4's, and NOS 6SN7's. I have tried Electro Harmonix, and KR 300's, the supplied Valve Art tubes being the worst. The true improvements came with the Sophia's. Now the sound is spectacular with only the bass being bettered by the KR's. The only other time I truly enjoyed digital was with the Atma Sphere M60's. I think from memory the M60's may have had a bit better control over the bass. I am a fan of OTL's, and will ultimately buy one. Nothing has gone wrong will an OTL in a very long time. So the people that are afraid of what they might hurt should go back to the stone ages.Otherwise both perform very well. The Coincident's being less expensive is what made it a better choice for me.
Still with the Atma-Sphere's. It has been about a year since I heard them. I had taken my older ProAc Response 2's under my arm to dozens of stores listening to their best and most musical amps. At this point I must aggree with Arthur Salvatore of highend-audio.com that the more expensive solid state amps do not sound as good as the more economical tubed versions.
The majority of my observations of the Coincident 300b's have been with Coincident's Victories coupled with an REL sub. I have now ordered Mr. Blume's new and improved Total Victories with the Victories being sold. I should be getting the TV's in the next two weeks. After the initial 100 hours of breakin I will let you all know how the combo sounds.
Until I receive the TV's I am using the amps with my ProAc Response 2 speakers. These are not ultimately the most tube friendly, but the sound is still well controlled and beautiful in the mids. The tweeters are not near today's state of the art. These speakers where slightly better with the Atma-Sphere's, but not by much. I had the Coincident Victories for a while and I do miss them since their sale. The tweeter in the Victories is simply outstanding. But the mids in the ProAc is also incredible.
I believe at some point I am going to upgrade to the Tenor 35wi's. These funds will not be available till after the summer. This is because I have a roofing company, which is seasonable. Being divorced also helps. I no longer have to renovate rooms that have already been renovated, pay for long shopping sprees, or pay for extravagant trips. But I digress. I will than be able to give you a comparison of the 300b amps to the best in the world.
EMM front end. Acoustic Zen and Audience interconnects with Coincidents TRS speaker cables.