I do not get deliberately adding barely perceptible distortion to the whole song to "sweeten" it.
In one of my email 'conversations' with Peter Aczel (which we turned into a feature in his Webzine) I asked him about 'dry' and 'lifeless' sounding recordings, and ways engineers overcome that. He replied:
Your Levine/Met recordings of the Ring sound a bit sterile because they were made in Manhattan Center (New York), which is an acoustically rather dead venue. In 1989, Max Wilcox produced a wonderful-sounding recording of the Mahler 5th (Mehta/NY on Teldec, released 1990) in that same Manhattan Center. He added some very subtle artificial reverb, which is not at all perceptible as such but makes the sound come alive.
Of course this sort of thing is 'baked' into the mix, and of course few would want reverb (or any other effect) in a constant 'on' state,
as part of their preamplification. Better to use an Aphex that you can switch in and out.
However, given the low level (from an actual auditory recognition standpoint) of any additive tube based distortion, this thing (or most any tube thing) is not going to be noticeable, if at all--at least in casual listening. Those second (and subsequent) harmonic distortion spikes will be masked by the music. Are those spikes going to ruin listening, at the 'macro' level? I'm not going to say they couldn't. And maybe a keen ear could find an isolated passage, put that into a loop, and A/B it with something cleaner, and then reliably tell each apart, based on the audible distortion.
Obviously anyone who argues for 'as clean as possible in all situations' is not going to go for tubes. Why would they? Again, anyone interested in this thing is interested in it for its 'vibe'... tubes sticking out of the top, and its overall design. Sure, the tweako press can and will argue about how it sounds this way and that, but people commonly hear 'differences' in the same gear on different days. Most of it, if not all, is imagination.
I get the fact that ASR is engineering based. That's why we are here. ASR serves an important purpose given that angle. But I've argued before, and will argue again, it makes no sense to compare tube engineering with SS, on an absolute basis. If you are going to compare the best possible engineering that can be got from a tube design, it should be compared with other tubes, like against like. However no one does that. It's just, "Let's stick this on the bench and compare what these half a dozen tubes do against a Benchmark..." Well, I think we can all agree that that certainly tells everyone what they don't already know.
To use a perhaps stretched analogy, if I'm comparing four legged animals that can pull a wagon or cart, I'm going to investigate the water buffalo, a domestic ox, some mules and donkeys, and maybe a goat. I'm not going to compare those animals against a cheetah, antelope, or even a thoroughbred racehorse, even if I could hook them up to my cart or plough. On the other hand, if I'm looking for the fastest land animal, and using a stopwatch, it's a different situation.
Getting back to Aczel, it's why he didn't bother reviewing tube gear. For his purpose (the best engineering at the lowest price), both he and his readers were not interested. Peter understood that tubes could never play that game, and that life is too short to expect the unexpected.
