Tube Amplifier Sound Characteristics


I wish there were a scatter diagram one could put together of tube amp sound qualities. The reason I say this is that today's tube amplification can range from sounding warm and romantic to cool and solid state like.
I like the sound of VTL, Quicksilver and Antique Sound Labs. I am in the market for a tube power amp and as I shop I see where more and more amps do NOT sound like tubes at all. So where would the sound characteristics of the 3 amps I mentioned be? For example I was considering the ARC Ref75SE but owners tell me it is SS sounding. Your thoughts are appreciated.
jimbones

Showing 2 responses by sbank

Like any topic, it all depends on how much you want to dumb it down on the spectrum from peer-reviewed white papers at one end and Twitter posts on the other.
With so many variables at play I don't think a simple warm-cool linear scale is enough to make an informed decision. It might let you cross a few brands off a big starting list. 
A more useful but still digestible format might be similar to how some reviewers rate ~10 attributes and score each on a 1-10 scale. Even rating a few amps you know would take some work.

Honestly, I think familiarity with the nature of various tube types is one of the most critical aspects of what OP is trying to solve for, maybe more than the brand name. Joe's tube lore is a good source for small signal tubes, but I don't of anything similar for common amp tubes. 6550s, EL34s, OTLs w/6AS7s, KT88, KT120, KT150 and little EL84s all have their own characteristics that are a big piece of the puzzle. Sure, circuit design, other parts quality, etc. also contribute. 

Choosing tube amps without knowing tube types is like reading the Torah(they don't print the vowels!). It can be done, but is a lot easier if you understand. Cheers,

Spencer