In 1982 Sony used the phrase "perfect sound forever" as I recall. But perfect is a metaphysical term anyway.
Edison presented live vs recorded demonstrations where listeners could not tell a difference.
So did Acoustic Research in the 60s, with the same resuts.
Edison presented live vs recorded demonstrations where listeners could not tell a difference.
So did Acoustic Research in the 60s, with the same resuts.
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I used to live just outside the 495 belt in Massachusetts, but that was 25+ years ago. Too bad; I'm in the PNW now, only a whole continent away...
Hificcl,
Let's talk - depending where you live, I'd like to stop by on my next trip thru MA.
The Montreal Audio Show (Sound and Image) is the last weekend of this month. You should go with your "innovation". [If its a headphone. I'm actually looking for a new one]. Montreal show is a lot of fun - missed it over the last two years.
Charles
Let's talk - depending where you live, I'd like to stop by on my next trip thru MA.
The Montreal Audio Show (Sound and Image) is the last weekend of this month. You should go with your "innovation". [If its a headphone. I'm actually looking for a new one]. Montreal show is a lot of fun - missed it over the last two years.
Charles
Hmmm, that's cutting it a little close to the line for me. I don't get the frame for my next prototype until the 25th and I still haven't figured out a head mounting mechanism yet since the drivers are odd shaped at an odd angle and I can't really work on that until I have the frames.
I also don't have the parts to complete the amp yet, they require significantly more power than full sized speakers. They are like a black hole of inefficiency.
I have a plan to resolve this and make them require only a few watts if it doesn't reduce the sound quality in the process but that is another bout of R&D that I don't have time or money to complete at the moment.
My other more efficient prototypes have been disassembled for parts.
I did order a 3d printed version of the frame that should be here next week, I'm testing if it has the strength, durability, and tolerances required to replace aluminum as it is much lighter. I might be able to do something with that, but I also need to pay off $10k in debt within a couple months so I need to work my **** off this month, I also just crashed and ripped apart my car in an ice storm the other day, I'm praying they don't render it totaled.
Bad timing in general. My intent is to have it complete by May.
Send me a PM though, we can plan something out 🙂
I also don't have the parts to complete the amp yet, they require significantly more power than full sized speakers. They are like a black hole of inefficiency.
I have a plan to resolve this and make them require only a few watts if it doesn't reduce the sound quality in the process but that is another bout of R&D that I don't have time or money to complete at the moment.
My other more efficient prototypes have been disassembled for parts.
I did order a 3d printed version of the frame that should be here next week, I'm testing if it has the strength, durability, and tolerances required to replace aluminum as it is much lighter. I might be able to do something with that, but I also need to pay off $10k in debt within a couple months so I need to work my **** off this month, I also just crashed and ripped apart my car in an ice storm the other day, I'm praying they don't render it totaled.
Bad timing in general. My intent is to have it complete by May.
Send me a PM though, we can plan something out 🙂
And such thresholds are what? Not absolute limits. They are estimates of an average limit of audibility (or threshold of pain, as the case may be), for a population. It is an estimate of the point at which 50% of the population won't be able to hear below that SPL (or will experience pain), and the other 50% of the population can still hear below that level (or not experience pain). Also it applies to sine waves only, which is what was used for the testing. We now now that human hearing is quite nonlinear and non-time invariant meaning that we cannot rely on Fourier to make engineering estimates of audibility for non-sinusoidal waveforms. The old psychoacoustics is in the process of being updated and or replaced by the newer field of 'Auditory Scene Analysis."
https://www.frontiersin.org/article...s (ASA) refers,sound waves reaching the ears.
Mark, would you care to think about what you just wrote wrt to 20Hz audibility? Even if some people have golden feet to pick up LF they will still roughly follow the nearly century old F-M curve which means a real music signal will be picked up from the harmonics. But good to see you have a new hobby horse to go on and on about 😀
Using my drivers, the audibility does not fall off too hard until about 5hz. If I pump the volume up, I can hear down to 1hz, although that's basically abusing the drivers so I don't usually do that.
Certainly no pain going on and I've done the test with others to make sure I'm not a super human.
As I said, it's easily demonstrated so saying I'm a liar is unproductive and not worth me discussing.
Certainly no pain going on and I've done the test with others to make sure I'm not a super human.
As I said, it's easily demonstrated so saying I'm a liar is unproductive and not worth me discussing.
Bill, Years ago I had some Sony open-ear headphones. I hooked up a sine wave oscillator to a DC coupled amp and found that the lowest frequency I could hear was 5Hz. Don't know if the headphones stopped working at that point, I reached my personal limit at the time, or maybe both. I ran the oscillator down continuously starting from around 100Hz and listened to see if there was a change to hearing a harmonic rather than a fundamental. The sound kept smoothly getting lower and lower pitch without any other change in the perceived sound character. I was particularly interested to see if the headphones would produce more harmonics as the frequency was lowered. I found no perceptual evidence of a point at which it sounded more like harmonics, or more like the higher frequencies I was listening to only maybe a second or two before.
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I have to call out your major BS on this. Listening to some teeny tiny transducter trying to reproduce ULF, all you are hearing are the distortion products that happen to lie within the normal range of human hearing. Distortion can easily be 100% or more, so plenty of that to hear. You are NOT hearing the 1Hz or 5Hz fundamental.
I originally considered this, but the smoothness and cleanliness of the transition of ultra clean sound all the way down has no perceptible artifacts. On a sine sweep it simply sounds like the frequency changing as normal. Even if it were some amalgamation of distortion, it is imperceptibly different and therefore practically irrelevant.
Although I do have a pile of REW measurements, the one with distortion showed a faction of a percent distortion throughout the range of frequencies if I recall. If it was large in the LF I certainly would have taken note.
I'll have to see if I can find it.
Although I do have a pile of REW measurements, the one with distortion showed a faction of a percent distortion throughout the range of frequencies if I recall. If it was large in the LF I certainly would have taken note.
I'll have to see if I can find it.
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Perhaps hearing tectonic tremor is an acquired ability for some who lives around bay area. 😉
Harmonic distortion is just a related tone (an overtone), the next higher octave same note, etc. Even large amounts of distortion can still sound somewhat "normal". When you sweep frequencies you probably would not notice the buildup of HD until at some very low frequency that is in fact all you can perceive.
The ear is increasingly less and less sensitive to pressure below 20Hz. Even at 20Hz a "pure" 20Hz tone is not a "note" per se. At high SPLs you feel it more than hear it, and what you hear is mostly the distortion. 5Hz is two octaves below 20Hz and 1 Hz is more than FOUR octaves lower and the sound pressure threshold for "hearing" a tone is increasing at around 20dB per octave below 20Hz (see Fletcher Monson, ISO 226:2003, etc.). There is really no way that your little earphones are generating enough pressure to hear the fundamental, but because of the steepness of the hearing threshold curve you can easily hear the higher distortion products, themselves just related "tones" that will sound "similar".
You are very likely just fooling yourself here, and you are nothing special within humanity and do not have infrasonic hearing. Keep in mind that I am not saying you didn't hear sound, just that it was not the fundamental that you heard.
Once in the very early 2000s when I was getting into DIY audio I build a large subwoofer using a 15" driver and two 15" passive radiators. It was tuned to around 30Hz. I went to a DIY meet in a large space, and someone put on some organ music. I was surprised and so proud that my new subs could reproduce the 16Hz pipe, until a more senior member pointed out that I was just hearing the distortion products. So, been there.
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If it quacks like a duck, and it walks like a duck. For all intents and purposes, it's a duck.
And the duck doesn't care if the world is round because he walks on a flat plane.
I have no interest in whether it is academically distortion or a pure signal. It sounds precisely like a pure decreasing sine wave, and therefore, it is.
And the duck doesn't care if the world is round because he walks on a flat plane.
I have no interest in whether it is academically distortion or a pure signal. It sounds precisely like a pure decreasing sine wave, and therefore, it is.
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Well then feel "free" to enjoy your fantasy 1Hz tone heard via your headphones on your flat earth! One claim is about as believable as the other.
If you stick your head in the sand far enough, its is possible to convince yourself most anything is true.
If you stick your head in the sand far enough, its is possible to convince yourself most anything is true.
Yes that is common knowledge. One manufacturer of an active speaker even had circuitry in some product that synthesized a couple of harmonics when a low note was detected, so listeners could swear they were hearing 10Hz. I won't call them out but the brand ends on ose and starts with a B ;-)
Jan
I think it will be hard to be successful in this business if you don't even understand perception.
But I'm rooting for you.
Jan
Right, well. Clearly the internet warriors here are more interested in winning online academic debates than developing practical advances in equipment.
I guess ya got me. I'm debunked, ruined even. Well done sirs.
To the others that care about tangible, real-world results, let me know if you are interested in a demo or joining my efforts.
I guess ya got me. I'm debunked, ruined even. Well done sirs.
To the others that care about tangible, real-world results, let me know if you are interested in a demo or joining my efforts.
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Extraordinary claims require extraordinary evidence. So far you only gave us "well I heard such and such". It's kind of coming up short, especially when it contradicts known human experiences that were established as much as 80 years ago and have been verified since.
If you indeed have some breakthrough technology that is super tip top secret and will revolutionize some aspect of audio I will be rooting for you but will cautiously await independent 3rd party verification. I think you will find others will do the same. Good luck getting over the hump with your endeavor.
If you indeed have some breakthrough technology that is super tip top secret and will revolutionize some aspect of audio I will be rooting for you but will cautiously await independent 3rd party verification. I think you will find others will do the same. Good luck getting over the hump with your endeavor.