Originally Posted by arnyk
I think the above paragraph has just about everything wrong.
There is nothing wrong with what he said Arny. Your test lacked any kind of control. If you knew you were testing clipping, you should have tried to have a sample that was highly clipped as to make sure the test, listeners, and scoring, all detect it appropriately. As it is, we have no idea if any of that happened. For all we know, as I showed with the AVS Forum blind audio test, that your scoring was wrong and no difference was found!
My wife used to be a lab technician in a hospital. At the start of every shift, they would run sugar water through their machine as a control to make sure it could detect it correctly. It mattered now how expensive the machine was, or that it had generated the right result countless days before. The protocol stipulated to always start with a known snapshot of the machine's performance. Likewise here, we need such a control in audio test and sadly that is what is always missed. The results always have a fog of inaccuracy as a result.
the HFN&RR article that I co-wrote has never been publicly criticized by any credible authority for any procedural problem. It is thus safe to say that Its procedures are just fine. BTW the article was published in 1982 - a mere 32 years ago. Talk about dredging the archives in a desperate effort to make trouble!
Oh, the "as far as I know" argument.
We don't know what you know Arny. What we know is that this is the first time this test has ever been published online. I pointed out one potential issue with it above. If we had an independent observer audit the work, we may have found other problems. I know what you are going to say: you are beyond any mistakes. Here is a good test case to counter that. The Boston Audio Society blind testing is put forward as expert witness and evidence by our camp all the time. Here is one of their tests: http://www.bostonaudiosociety.org/bas_speaker/abx_testing2.htm"I expressed my desire to try the test, and Remington went to cue up the record again, but I requested to be allowed to undertake the test with no signal passing though the system. Before realizing the import of what he was saying, Vanderkooy interjected: "Ah! You're going to listen to the sound of the relays." Yes, there is indeed a slight audible difference between the acoustic "click" made when the "A" and "B" relays pull in. This is due to the unavoidable differences in the mounting positions of the relay on the A/B/X box chassis and, although slight, it can be heard if one listens for it. I replied that I was going to listen to the difference in background hiss, and the subsequent series of blind trials showed conclusively that the two signal paths could be reliably distinguished on this basis alone."
I have highlighted the key section. Had professor Vanderkooy not been there, it is entirely possible the person being tested could have gamed the results and we would have an egg on our face making him a hero instead of zero. Fortunately we got lucky there that he did not try to listen for the clicks and were made aware of our testing protocol mistake.
(2) It has always been clear to everybody officially involved with ABX that as the article was entited, "Some Amplifiers Do Sound Different". It is true that some people troll with the phrase "All amps sound the same". All generalities that global are false.
Amen to that!
Let's be absolutely clear that you are agreeing that two solid state amps can sound different. In all of these arguments you usually bring up low power tube amps as an example of amps sounding different. Have not heard you say two solid state transistor amps can sound different.
Obtaining positive or negative results in ABX is as easy as knowing which equipment to choose to compare.
Say what? You mean you played a game in that article in order to get that headline of amps sounding different??? Tell us that is not true Arny.
If you actually bothered to read the 1982 HFN article that you brought up, you would know that its positive results were based on playing back LPs. This fact makes the above question look pretty strange. Want to retract it? BTW, the actual tests were done in the spring of 1981 when CD players were as about as rare as hen's teeth.
There is absolutely nothing wrong with what he said. He explained that if a difference between two amps was heard with LPs, that difference does not go away when you increase the fidelity of the source, i.e. use digital. What is your basis for disagreeing with that?