Originally Posted by communic
It's been a while since I've studied physics but from that example, then yes if you keep amplitude the same then the frequency has to change, no two ways about it. This would also mean that you would indeed be hearing music different to how you have heard it before (pitch) and if the diaphragm was ready to move on to the next wave instantaneously, would result in a quicker track.
However, mvw2 I understand you can keep the frequency the same even if acceleration and deceleration of the wave is different for two peaks but surely it would mean amplitude would be alot higher or lower as average_joe pointed out and not sure how that translates to 'body' of note as you say. Assuming the peaks and troughs within an individual wave are irrelevant then surely you would experience the same body regardless of the amplitude the diaphragm sent out?
OK, #1, I made a mistake in my post (yea, I am human). 5ms is a 200 Hz signal, and if you take the positive part of the wave, it is 2.5ms. So, lets say the positive movement should take place for 5ms, a 10ms total wave, a 100 Hz frequency. If half the cycle was 3.5ms, the wave would be at 143 Hz.
Part of my point was that knowing/remembering/understanding physics is important for this discussion, and to me there have been things that have led me to believe mvw2 is lacking somewhere, not that I am perfect. I guess I proved that there are even differences between understanding and knowing/remembering all the important details.
While on an absolute scale 100 Hz vs 143 Hz does not seem that big, on a logarithmic scale it is a biger difference. Along with how it is produced, it is not a pitch change, it is a change in the base note. As oarnura stated, it seems like new physics is being created, the output is greater than the input without any additional energy. And that violates conservation of energy.
And from my understanding, waves don't have acceleration/deceleration, that is a physical property of sound producing element. The wave has amplitude, wavelength, and shape.
Originally Posted by bakhtiar
Before that we must understand what is sound waves. Why different musical instruments produce different tone/sound characteristics even though at same musical note, example 440Hz? This is because the sound are not made from a simple sine wave. They mixed together and create the sound that we used to hear.
I would like to introduce a tool which is, IMHO, the BEST sound editor I ever use. SND The Snd Home Page
. I am using the software to analyze and understand more about sounds. Yes, this software is complicated, but VERY powerful. There are many examples which you can read and understand about sound. My favorite is a birds/animals sound synthesizer program.
Sorry, I have to go now.....
I think we are talking about sine waves because they are simple waves, easy to produce and reproduce by drivers. And yes, different musical instruments produce different sound wave shapes with different harmonics.
Thanks for sharing the sound editor, I will check it out when I get a chance.