The other frequency has to be as non-masking as possible. But, yes, the presence of another frequency can expose a sound below the threshold of audibility.
Maybe think about it this way: Sometimes the low level signal is a little wiggle on a high level waveform that is at a high absolute SPL. In some cases that can shift the low level signal into audibility.
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Like I said, some research links were posted in another thread. I just have to find them. It was in response to a question by DF96, who raised the possibility.
Ok, that's not quite what you said. It's broadband noise, not a tone and it is modulated so that the masking is coming and going so one would expect unmasking to occur as the modulation increases. What is unexpected is that the unmasking increases as the noise bandwidth increases. That is harder to explain, but still a rather unique set of parameters. I don't think that it would have significant effect on audio signals - nothing even close to the standard masking effect.
Most people are happy listening with an i-phone and basic headphones. As long as they can enjoy their music. (aka 20% THD)
Each person has a different ability to interpret sounds and music. We learn this as we grow up from childhood to adulthood. The first time we hear music it was all confused and mysterious, then in kindergarden we learn to sing and remember melody and some rythms but we still have no sound/quality objections and references. Everything sounds good.
With education and learning, sounds become organized in our memory like words. We only remember what people say when we learn to speak. I could only remember music, chords and rythmn after I learn to play music. Otherwise it was a limited ability and remained disorganized and mysterious.
Without Learning formally to play instruments, sing, harmonics and music theory and notation, most people have no references for sounds but their emotions or first impressions.
Each person has a different ability to interpret sounds and music. We learn this as we grow up from childhood to adulthood. The first time we hear music it was all confused and mysterious, then in kindergarden we learn to sing and remember melody and some rythms but we still have no sound/quality objections and references. Everything sounds good.
With education and learning, sounds become organized in our memory like words. We only remember what people say when we learn to speak. I could only remember music, chords and rythmn after I learn to play music. Otherwise it was a limited ability and remained disorganized and mysterious.
Without Learning formally to play instruments, sing, harmonics and music theory and notation, most people have no references for sounds but their emotions or first impressions.
IIRC, a reference was found somewhere to what I said. At the moment, I am looking through this one which looks interesting: http://www.jneurosci.org/content/jneuro/21/16/6377.full.pdf
Don't know if I'll find it though.
Don't know if I'll find it though.
I don't see that as true. I have no formal training in playing an instrument and don't play one at all, but my musical appreciation does not seem hindered by this fact. I have always been a fan of music from very early on as a child.
Language has a huge impact on how we hear. For example, in Chinese the meanings of words are carried by the tone, not so any Romantic language, tone is an accent, it caries little to no meaning. But in China the number of people with perfect pitch is in the high 90's. In the west it is in the mid teens. We don't learn to hear what is not necessary for our development.
This is also why we cannot hear above about 10 kHz. There is simply nothing in our environment above this frequency because even if these frequencies did exist, air absorption, which increase dramatically above 10 kHz, simply dissipates it. So evolution just ignores these HFs. Not so, for small animals whose world is very short range and air absorption is not a factor. Small cats can hear to 30-40 kHz.
Okay, Here is some different research:
SAGE Journals: Your gateway to world-class journal research
The hearing thresholds and the perception frequencies of complex frequency tones
with higher harmonics in frequencies between 5Hz and 50Hz were measured. The
following conclusions were obtained.
(1) Hearing thresholds of the complex tone with harmonics decrease compared to
the hearing threshold of the pure tone, whose frequency is the same as the
fundamental.
(2) As the number of harmonics increases, the hearing thresholds of complex
tones decrease in many cases.
(3) A harmonic below the hearing threshold affects the hearing of a low
frequency complex tone.
(4) The hearing threshold of a low frequency complex tone is affected by the
phase difference between components
On the whole, it looks like sound characteristics affecting audibility are still being discovered. Personally, I would be hesitant to think we know it all. I'm pretty sure we are eventually going to find that sometimes some people can hear lower level distortion than previous research has found. Regarding Comodulation Masking Release, it looks like the masker doesn't have to be noise, but in most cases that is what has been looked at, so maybe we will find some more there too.
SAGE Journals: Your gateway to world-class journal research
The hearing thresholds and the perception frequencies of complex frequency tones
with higher harmonics in frequencies between 5Hz and 50Hz were measured. The
following conclusions were obtained.
(1) Hearing thresholds of the complex tone with harmonics decrease compared to
the hearing threshold of the pure tone, whose frequency is the same as the
fundamental.
(2) As the number of harmonics increases, the hearing thresholds of complex
tones decrease in many cases.
(3) A harmonic below the hearing threshold affects the hearing of a low
frequency complex tone.
(4) The hearing threshold of a low frequency complex tone is affected by the
phase difference between components
On the whole, it looks like sound characteristics affecting audibility are still being discovered. Personally, I would be hesitant to think we know it all. I'm pretty sure we are eventually going to find that sometimes some people can hear lower level distortion than previous research has found. Regarding Comodulation Masking Release, it looks like the masker doesn't have to be noise, but in most cases that is what has been looked at, so maybe we will find some more there too.
Sean Olive said in one of his videos that young children can hear up 30kHz or maybe higher, but that by age 24 it drops to about 16kHz.
I've been there, you can ask for the most mundane thing and get stared at because of the slightest wrong inflection even when what you actually requested (to their ears) would be totally absurd.
That stat is interesting, considering how jarring traditional Chinese music can be to Western ears. You need need to experience 6 teenage kids playing Beatles covers on biwa and guquin.
That's what intrigued me, the concept of perfect pitch and traditional Chinese Opera is interesting. I wonder also about the incidence of perfect pitch as a curse where you can't stand to even listen to it off.
Well lots of ignorance in the tone symbol of PinYin these days, I could not understand what Chinese you guys are trying to express just reading. A friend of mine was trying to tell me which hotel and which street he was on, I could not recognize either regardless whether it was spoken or typed.
