Hey jcmusic.
I see now that yours is a very specific use. And being a complex system, and this particular use, representing a limited part of the spectrum, I can imagine how it might make ultimate tube choices more challenging.
But like caps, unless we want to try them all, in seeking a given desire for improvement, the best path I know is to get comparatives from others that describe the tendencies of a tube or cap based on its sonic traits and tendencies. Then we can try to interpret if those sonic tendencies might apply to our specific needs.
I agree, variability in different system/rooms, and personal preferences, are givens, and they define what is ideal in a given setup. But also, we see threads of certain tube's character conveying broadly across many systems. In this case, a bunch of us agree that Type 80s are compelling tubes, indicating they can convey their special traits across many systems. So we try to describe what we are getting in our setups in hopes it might help others narrow down choices. But finally, as with reviewers, reviews are most successful for us if we take into account the personal preferences we have come to expect from the writer and how we interpret their system/room as compared to ours. Always a risk for the hard core tuners, but hopefully this process gets us closer to guessing how something might work in our system.
Variabilities in tubes, setup, and needs were part of the reason for my recent posts. All Type 80 STs are not alike. And all Globes are not alike. But being Type 80s, each of these subgroups carry similarities, while each individual within each subgroup have their own sonic tendencies.
Leading to... For people with very specific needs, and resolving systems, refinement is trickier, with narrow choices, and trying one of a type and not totally loving it, does not necessarily rule out others of the same type. So clearly, a single Type 80 tube might or might not be the ultimate in a given setting, but this might not rule out Type 80s in general for that setting.
Some of us have tried STs and Globes, but few have heard the gamut. And with several different Globe and ST makes, and different vintages within each, we can expect notable sonic variations.... Whether Type 80 or ECC88/6922, or whatever tube.... When have you heard two ECC88s that sound exactly alike? Yet the type has expected traits that generally differentiate them from an ECC88/6DJ8, or ECC189.
So with two basic types of Type 80s, and a number of different makes and vintages of each.... in most cases each individual tube will exhibit variations on the type themes. So I agree, even if we know we have liked the type, we really can't tell exactly how well another tube of the type will slot into our systems until we try it. But then, plug and play is often not an ideal answer or conclusive. Many of us have found that if the traits of the new tube are compelling in most ways, then fine tuning with other tubes to bring out the best of each in combination, can potentially make the new tube that was not ideal, beautiful.
If we are seriously into optimizing sound in fine tuned ways, this to me is a very good reason to work up to at least several of each basic tube type we use, tubes that sound varied, but that we really like, especially in the right company. Then the ability for mixing and matching can result in yet unknown beauty. Based on mixing the traits of different known tubes for the very particular blend and synergy, then 3 or 5 tube positions are what we are tuning into one sound. With skill, luck, and trial and error, the tube type's combined traits can potentially create great beauty. So if we are really particular, I find the time and energy to bring out a compelling rectifier can be well worth it...
Round about, this is part of what I thought I was pointing to with my last post. We all know we have different setups, and Lon and you, in your rooms and uses, prefer the Globes you have over the STs you have. And for a long time I preferred Globes overall, but have also enjoyed STs at times. And for me, my globe preference was one Globe type, earlier Philcos.
Then I did this test yesterday without adjusting anything, no tube changes other than changing the Torii rectifiers from my
current favorite Telefunken RGN1064s, to only one Type 80 Globe, and only one ST type. And for this specific setup, plug and play, I prefer the Westinghouse STs I have over the Cunningham Globes I have. They both sounded really good, but for this tube set, with this limited test, and with very careful listening, I was actually surprised to like
this ST quite a bit better than
this globe.
Looking more specifically at tube variations within system variations, and the validity (or not) of the analysis of others as tools.... Being to my tastes, both my systems have similar traits, but are definitely different. And pre stages and amps each have different sonic qualities.... so different gear, power treatment, different tube combinations, different cables, different feet, etc, the combination creating the character of each system.
Yet I hear sonic fundamentals of any rectifier moving it from one amp to another, or one system to another. The same tube has the same sonic traits in all cases. Now depending on how the specific setup and room adjust those traits, defining what is "the best," is hard to say. But if I put in a Philco globe in any of them, I hear a Philco globe sound.
Obviously levels of listening discernment and communication efforts and skills also play into all the many wildcards inherent to how something sounds in a complex system... I personally have never gotten much from comments like "the best tube," or "the worst tube," without context. But also, "translation" of well perceived and written impressions most often requires interpretation as to how these impressions relate to our particular systems.
So I agree it all depends on a lot of things. But I have also noticed that tubes have traits that can convey pretty well, especially across Decware, all Decware voiced with Steve's preferred parts, and to his preferred sonic balance and "flavor."
My take anyway.