If you're referring to my comments, read my post again beginning with "Which completely misses the point".
There were no results, so I can't refute it or give a contrary cite. Just a few hand-waves in an internet post. If there's actually something substantive published somewhere, I'd appreciate you pointing me towards it.
The ones that either you or Sy have used to empirically refute FVA's results.
Or - are you just speculating?
What VFA results? There ARE NO VFA results, just bar-talk, and demonstrated wrong at that. Unless you are hiding it - show it and I will read it.
You criticize test issues that are addressed and taken care of in SYs article which you apparently have not had the intellectual curiosity to read.
Jan
Of course I read it. Have you? Test issues that are addressed? That's hilarious!!!
You mean like this:
"Nonetheless, if a particular hardware implementation
of the ABX test is found wanting, it is not difficult to construct an ABX box with whatever
switches or relays are deemed adequate for audiophile use. After all, the signal in an audio system has
passed through many switch and/or relay contacts during recording and mastering, and most audio
systems have source selector switches."
Which completely misses the point.... Again and again.
I understood "distortion" in a wider sense: every transformation of the signal: harmonic and transient distortion, memory effects, compression, frequency band limiting, etc. Some can be very little, and even pleasant to the ear.
ABX BOXES RELY ON SPECULATIVE ASSUMPTIONS AND ARE NOT SUPPORTED BY SCIENTIFIC CONTROLS THAT VALIDATE THAT YOU ARE TRULY COMPARING DEVICE A (BY ITSELF) TO DEVICE B (BY ITSELF)
You're a funny one! If I would refer to your comments, I would say so, otherwise it all is pretty senseless, no?
Jan
Well shouting doesn't help, really.
OK, so another content-free statement from you. Are you going to come up with anything factual or should I give up trying?
Hint: What are the 'speculative assumptions' ABX boxes rely upon? Which are the scientific controls that the ABX box should support but isn't? How then should we validate that we are truly comparing etc.? I mean you MUST have SOME idea of what you mean??
Jan
Perhaps something is getting lost in the translation. I point out the common canard used to defend ABX boxes - which is exactly what you use :
I'd like to comment on that tired old argument that the switches of the box would 'hide' the differences.
Agreed! Such is NOT the problem with them. The problem lies elsewhere.
OK, agreed. Although you should be surprised how often that is the first argument that pops up.
jan
There are quite a few types of documented distortion, and some that appear to be smoke screens. I read in a well documented technical journal that transient intermodulation distortion (more appropriately called "transitory" intermodulation distortion, ie TID) was in fact the direct result of slew limiting, and that it was impossible for it to exist in modern audio electronics. SID itself is not a distortion but a precurser to TID and a couple others. Apparently it was discovered in the 50's and helped with radio communication design.
20 Years later, a group of audio gear designers tried to say they discovered it, renamed it TIM, and of all things blamed it on high feedback. But, their paper was found to be faulted and contrived and was not accepted outside of audio publications. Later, a paper came forward that explained why the TIM article was wrong. In more recent years even Rod Elliot says that he's seen no evidence of this TIM distortion in wide bandwidth designs with low compensation and high feedback. I found it funny that the audio magazines capitalized on distortion that doesn't manifest outside of a boombox or computer speaker systems.
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You build an amplifier and it sounds good, you are happy. Then you build one with lower distortion and in most cases you feel it sounds better. If you hadn't the 2nd amplifier to compare with, you would have been happy with the first one. Often it's harder to perceive an improvement when you 'go up the quality scale' but easier when you drop back down it.
Here's the kicker- Otala actually wasn't the first person to identify the level of feedback had nothing to do with the slew rate limiting. In the 60's, Japanese designers were aware of miller pole compensation inducing the slewing effect prior to the first TIM publish date. One of the biggest follies of the TIM articles was, again, that they were laying claim to an already-discovered distortion that was documented and understood 20 years earlier by Roddam and Japanese engineers, called TID.
There was no internet in the 1970's, but I would have thought that Otala and Curl would have had to put their TIM paper through a screening peer review.
There was no internet in the 1970's, but I would have thought that Otala and Curl would have had to put their TIM paper through a screening peer review.
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