Its all suggestion and insinuation.
You can easily run the numbers if you know that 1% is 1/100 😎
And it's not recursive, that has been debunked, ohh, 50 years ago?
I remember reading about it as a kid ;-)
Jan
To difficult for me to do the calculations so simulated it with DSP in ADAU1452. 2. order distortion at -40 dB
The other measurement are 1k, 2k and 3k, same level into same x^2 and summed with source. At the right it is just some balancing going on
The other measurement are 1k, 2k and 3k, same level into same x^2 and summed with source. At the right it is just some balancing going on
Myself I did not hear any of this 1% second harmonics. Guess they are not golden ears any more😢
I played with a more complex harmonic generation algorithm on the adau1452.
I can adjust the THD level with an external potentiometer and immediately listen to how it affects the music in the speaker system. At the same time, the THD level is stable in frequency, but at a lower signal level, the THD increases.
Pictures and a file for Sigma Studio in post number 21.
https://www.diyaudio.com/community/...h-dsp-adau1452-100w-per-channel.410804/page-2
I believe this is the easiest way to determine your own threshold for perceiving the level of such distortions.
Seeking the math internet and found The 2cosacosb formula is 2 cos A cos B = cos (A + B) + cos (A – B).
And second order harmonic is squaring the signal.
So somewhere in the equation we have the 2k multiplied with the 3k, resulting in a 5k distortion component.Guess it happens twice so then it gets 6 dB higher than the individual HD components
May I ask at what levels you was on your threshold. Span or ballpark🤓
Guess my signal had to much masking effect on the distortion or that my headphones already distorted the original signal
The formula shows the generation of IMD, the sum and difference components as mentioned before.
18k and 19k gives 1k diff and 37k sum spectral line.
I'm not sure what the 2k x 3k = 5k means or where it is coming from?
Jan
I don't understand why you keep presenting these "some people say" talking points as if they were valid data. I mean... Maybe they are valid data, but you have yet to provide any reference to a study that tested these ideas.
Some people can hear the effect of speaker cable risers.
Some people can hear the effect of ground boxes.
Some people can hear the effect of plastic on the components.
The last one came from a guy I bumped into in a hifi store in Copenhagen some 25+ years ago. He was dead serious that he could clearly hear a difference from removing plastic from the components. And by that he meant that he'd removed the plastic sleeve on electrolytic capacitors that shows the part value, manufacturer, etc. He'd removed the plastic insert in the RCA connectors of his CD player (that he'd brought with him). He'd replaced the power cord with some wire from the 1930s that used silk insulation instead of PVC. To him the difference was clear as day. And, of course, it sounded more organic and less synthetic with the (synthetic) plastic removed. I'm not really sure how he planned to eliminate the polycarbonate plastic of the CD itself.
Some people say they can talk to the dead. I'd say, talking to the dead is easy. Getting the dead to talk back is the hard part. That's not my line. That came from Michael Shermer's TED talk: https://www.ted.com/talks/michael_shermer_why_people_believe_weird_things
Tom
The term "some people" is entirely appropriate, and you should already know why. All thresholds of audibility are estimates of the center of a bell curve, where the "average ear" sits right in the middle. Some 50% of the population are more sensitive than average, and the 50% of the population is less sensitive. Even the The Absolute Limits of Hearing are estimates for an average ear.
That's true for other personal attributes as well. Some people are taller or shorter, some have higher or lower IQs, some people are more or less hairy than average, etc.
There gets to be a real problem when we simplify our models of the world around us into absolutes.
Oh, that's nothing. I was on a listening session of a renowned HiFi magazine at a HiFi dealer in Regensburg/Germany. He claimed it's audible where the CDs are stored and you could clearly hear it because the material of the shelves would 'imprint' on the CDs. I gave him 3 CDs and asked him how it sounded. After his guesses "wood", "metal" and "glass" were wrong, he didn't dare another try. (I stacked them on top of each other on a stone floor)
The other atendees weren't so convinced they'd hear it either after that. They were kinda sour after that - they missed out on appx. 90k on CD storage racks sales I've heard. 😀
I was exhibiting at a trade show when a cable vendor showed up with a pair of XLR cables that were about as thick as a garden hose and about as stiff as said hose at -40 ºC. “Try them! You’re guaranteed to hear a difference.” It was a quiet day so I decided to play along. I first listened with my $5/each GLS brand cables. Then with his [undisclosed price] cables. I couldn’t hear any difference. So I tried using one of my cables and one of his. The vendor’s eyes just went POP! and his eyebrows shot to the ceiling. Apparently he hadn’t thought of that. If the difference is so dramatic there should be a huge imbalance, right? Yeah… No. As expected I still couldn’t hear any difference. I even reverse the headphones left/right to "test". The cable vendor left looking pretty defeated when he left.
Tom
Tom
Oh, I forgot.. there's actually a difference in sound if the boxes are standing flat on the ground and of them on spikes. The reason is, that the downwards dispersed sound is reflected if the speaker stands flat on the ground, more is reflected than if there's a gap below the speakers, which makes some of the sound running around the speaker (because of the edge diffraction) than being reflected. They had a set of 'high end' spikes 200-300 bucks a set. They nearly wanted to kick me out when I demonstrated that the speaker standing on 3 bottle caps was indistinguishable from the sound on the expensive spikes! 😀
If you're such a scientific expert you should know not to apply statistical methods to categorical data (can vs cannot hear CD dither).
Tom
No, its more a question like this: What is the probable percentage of the population that will measure 6ft 9inches tall during a physical exam with their doctor?
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Oh, don't even start on that! A friend said adamantly he only listenes to records, tapes and R2R
claimed 'I don't want to hear steps!' - until I showed him the waveform of a high-end test signal record and a CD with the same signals on a scope! He didn't even knew what to say anymore and just left completely deflated.