In a universe where, "... meteors, traveling at the speed of light ... " is real, all things are possible, including two devices sounding different after passing a null difference test. 😂
Why HiFi Gear Measurements Are Misleading (yes ASR talking to you…)
About 25 years ago I was inside a large room with an A-frame ceiling and large skylights, during the Perseid Meteor Shower that happens every August. This one time was like no other, for two reasons: 1) There were large, red, fragmenting streaks multiple times a minute with illuminated smoke trails, and 2) I could hear them.
Yes, each meteor produced a sizzling sound, like the sound of a frying pan.
Amazed, I Googled this phenomena and found that many people reported hearing this same sizzling sound associated with meteors streaking across the sky. In response, scientists and astrophysicists said it was all in our heads. That, it was totally impossible. Why? Because of the distance between the meteor and the observer. Physics does not allow sound to travel fast enough to hear the sound at the same time that the meteor streaks across the sky. Case closed.
ASR would have agreed with this sound reasoning based in elementary science.
Fast forward a few decades. The scientists were wrong. Turns out, the sound was caused by radiation emitted by the meteors, traveling at the speed of light, and interacting with metallic objects near the observer, even if the observer is indoors. Producing a sizzling sound. This was actually recorded audibly by researchers along with the recording of the radiation. You can look this up easily and listen to the recordings.
Takeaway - trust your senses! Science doesn’t always measure the right things, in the right ways, to fully explain what we are sensing. Therefore your sensory input comes first. You can try to figure out the science later.
I’m not trying to start an argument or make people upset. Just sharing an experience that reinforces my personal way of thinking. Others of course are free to trust the science over their senses. I know this bothers some but I really couldn’t be bothered by that. The folks at ASR are smart people too.
Showing 3 responses by tsacremento
@amir_asr, I have a few questions regarding measuring equipment. Genuine questions, not “poking the bear” nonsense.
As we know, all of the individual components in any particular model have specified tolerances, typically ranging between +/- 1% and +/- 20%. Is it possible for a measurable performance difference between two random samples of the same model to result if some of those tolerances stack up one way vs. another, and, if so, can the measured differences be audible? If measurable differences between two otherwise identical units are possible, then what would be the random sample size necessary to generate a reliable prediction of worst-case, average, and best-case performance?
Some of the units you have tested were provided directly by the manufacturer or distributor, raising the question of whether or not you received a “golden sample” for your testing. Some of your test units that were submitted by members were discontinued years ago, and many of those were provided by individuals who bought them used in unknown condition. Does either of these situations lead to any additional scrutiny with respect to those units being representative samples?
Thanks in advance for your insight. |
@amir_asr, thank you for taking the time to provide clear and unvarnished responses to my questions. Much appreciated. From reading through many test results on the ASR website, it appears to me that achieving ultra-low SINAD performance is almost trivial for good line-level electronics, but not so much for power amps. Am I not interpreting the test results correctly, or is this true? If true, is this issue due to the amount of gain required? Thanks again. |