I bought the classic 45 after comparing it to AP 33 at Mike's 4 years ago. I had to wait to find a copy, the classic 45s is hard to come by. I found a mint unopened that stays packed. I use the AP 33 for auditions.
Jazzhead has a room that's 11 feet wide and 25 feet deep. Sounds excellent with the Marten 2. You will need to pull up the speakers and seat pretty close instead of keeping a lot of length between the two
You Should try RK 5u4g from KR. it's 400 quid or so. The difference in Allnic sound work rolling rectifiers is significant. It's also a change in character from stock recti. I haven't tried Sylvania with Allnic but tried with Lampi and KR / RK are much better.
Maybe Fremer can clarify what he means by the term "black background" as readers might be interpreting it various ways. Microstrip somewhere mentioned to him it was the absence of artefacts, which is a positive definition, maybe Fremer can clarify what he means by the term