Hi, I was considering getting the newer TVC with Double C Core. I did write Nick about this and haven't heard back from him yet. Wanted to get the TVC in a single box, like Rev 5, but with the Double C cores in there instead of the standard transformer. I was also thinking about the tube preamp. So here I am looking around.
Ray,
The Apollo preamp is also an excellent preamp. I got an used one in audiogon and replaced all high quality components except the Double C-cores and TVC trans and wires. I personally do not like the sound of 6N1Ps. Therefore, I swapped them with 6922s (since I found a very nice sounding pair of NOS ECC88/6922s in my closet) by following Nicholas instruction. It turns out to be more than excellent preamp which matches my sonic tastes. I had a couple TVCs but somehow there was a sonic weakness in my system with TVC only. So I thought I would need a tube buffer stage for TVC. I also have tried a separate tube preamp used with TVC but that combination did work well in my system too.

Tan