audible distortion and tube gear?

@everybody, thanks for the input.

@soix

but if you share what equipment/cables are in your system and what CD you’re using you’ll likely get much better and more useful insights here. Good question though.

Equipment is Maranzt SA10 in front of Cary SLP 05 in front of Cary V12 in 50 wpc triode in front of those B stock Revel M126Be’s that I am auditioning. Components are connected using the balanced outs and ins with Kimber Silver Streak XLR. The speaker wire is Kimber but I do not remember the model # (I bought the wire back in the ’90s, but there are multiple strands of blue and black insulated wire). The disc is "My Disc" (The Sheffield/A2TB Test Disc).

@atmasphere

With a pure sine wave, higher orders added are easily heard since our ears use them to tell how loud sounds are (so are keenly sensitive to them); you need a bit more distortion for the lower orders (2nd and 3rd) to be audible.

the tone I was originally inquiring about is, I assume(?) a pure sine wave? The description says that the first reference track is 0.0004% distortion and then the following five tracks are: 0.1% distortion, 0.3% distortion, 1% distortion, 3% distortion, 10% distortion.

I got to messing around some more with this last night, and this time I was sitting up (as opposed to reclining back) and looking down at my sound level meter (so my head was higher and more forward than the previous times I had tried to identify distortion using this CD). The description says that, "Distortion is the slight buzz mixed in with the pure tone." I’ve never heard what I would describe as a "slight buzz." However, sitting up and looking down, as opposed to reclining back and gazing ahead at a slight upwards angle, I guess I did hear the tone change somewhat as it switched to the final track. I don’t think that I would call what i heard a "slight buzz" though.

My ears have suffered cumulative abuse over the years and I am pretty sure that I have lost some frequencies. Does it seem plausible that I have lost the frequency that the "slight buzz" is on? Also, I suffer from tinnitus (however when I am listening to music I do not notice it); could the tinnitus be at the same frequency, or close to it, that the "slight buzz" is on, and that is why it does not absolutely jump out at me?

After the consecutive tracks that are what I believe the pure sine waves you refer to, are 5 consecutive tracks that repeat a short musical passage with the distortion being increased in the same increments as before to 10% . . . I am going to listen to those (musical) tracks some more, but so far I honestly cannot tell the difference between any of them no matter how I position my head.

@immatthewj The designer of the CD probably didn't understand what makes distortion audible to the ear. So they probably just added harmonics to the signal without doing anything else.

One of the things that makes distortion more audible (especially higher ordered harmonics) is if distortion rises with frequency, which is common in most amps with feedback but likely wasn't taken into account when the CD was created.

If you have hearing loss or other problems at the frequencies at which the distortion occurs, you might not hear it. But others around you might- if they are yelling at you to turn it down that's a clue. A good system never sounds loud until over 95dB or so. If it sounds loud below that you know you have a distortion problem of some sort.

@atmasphere  , thank you for getting back to me on that.  As always, I appreciate the education you provide to me.

Distortion is a personable sort of thing, likely reserved for 'umans.  One could say all music and it's varied instruments just create "liked through loved" distortions not natural in nature.  That, combined with a distort we call 'a beat' that likely began as a distort of a heartbeat.....

All audio gear has a level of 'good' distort v. 'bad' distort.

It gets discussed a lot 'round here.

It seems to get steered by taste, tolerance, and budget.

....no to mention the Final Arbiter...

SAF or SOAF.