Yes, I'm trying to show the result of the brickwall without any extra signal processing. Down sampling from 192k to 44.1k includes by necessity the brickwall filter. In general you don't send the 44.1k data directly out of your DAC it gets OS. Both of these processes involve choices of filters, etc. I have gone through the exercise with Audition and or Audacity the differences are usually slight but they don't offer the unusual filter options.
Agree. The instant the string is released, max acceleration, there is no kineteic energy to convert to signal. So the attack takes some time, as the velocity builds. Which coresponds to the acoustic version.
Expand all you want, its still the sum of 2 sines and if i notch one out I end up with one sine.
Modulation of the type sin(20)*cos(4) gives both 16 and 24 khz content. Filter the 24, all that remains is the flat 16.
Modulation of the raised sine type produces 16, 20, and 24. Filter the 24, you have 16 and 20 left.
The sum of a 16 and a 20 sine is equivalent to 2sin(18)cos(2).
Be careful which modulation type is used. Raised sine modulation is not a natural modulation in music.
Jn
Of course. Nobody disagrees with that.
That said, the envelope of two sines added is cos((a-b)/2). Assuming they are of equal amplitude
Jn
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But not of the fundemental? But all components combined, so faster than 1/4 cycle of the fundemental.
But the string needs to be moved from the rest position to the release position. as long as the sampling system has a low enough HPF then this will also be recorded. So no discontinuity. All of which is of course completely ignoring how sound is made in a plucked instrument 😀
At least twice in the last 7 days and dozens of times before. You may have infinite tolerance, but I have to save my reserves of that for my kids. I am afraid I am intolerant enough to have got bored of it over the years and yearn for something from the 21st century from John.
While this describes the value of the sum, it's not a mechanism for generating new frequencies. I think the multiple uses of the word "modulation" is getting us all into trouble.
Modulation meaning "turning a volume control up and down at 4KHz" is not the same thing as modulation meaning "mixing two signals together in a multiplier". Only the latter produces new frequencies. Linear addition of two signals is not the latter.
All good fortune,
Chris
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Isnt envelope a lot slower than the carrier, basically flat for a signal thats just carrier. ( or 2 carriers of different freqs). For music, envelopes are slow think VU meter. The envelope of a held oboe note is flat, dosnt matter what all the harmonics are doing.
Agree that addition doesnt make new freq, but turning volume does. Output=Signal X gain. If the gain is a 4 khz sine than you have AM. Altough choosing a 4k sine which is in the middle of the music makes which one the carrier? The parradox for me: if you take this new signal with the new freqs and run it thru the amp again only reverse the volume moves you should get the exact sgnal back. ( i turn the preamp up at the same rate I turn the amp down). So what happens to the extra freqs from the first modulation?
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And if adding 2 sines creates new freqs, 2 flutes playing a cord would create dissonant freqs, dosnt happen.
My goodness...
This is the time when I lament the lack of a gallery here. It would be so much easier to explain with clear plots and explanations..
So, where to start??
I know...with a beer.
Enjoy the rest of the evening guys, it has been interesting.
I'm off to make some metal chips.
Jn
This is the time when I lament the lack of a gallery here. It would be so much easier to explain with clear plots and explanations..
So, where to start??
I know...with a beer.
Enjoy the rest of the evening guys, it has been interesting.
I'm off to make some metal chips.
Jn
Two flutes can't play a chord since a chord requires three or more different notes.
However, two flutes can play an interval of a diminished fifth which is said to form a dissonance according to classical music theory. The dissonance in that case would seem to be the same sound as JN suggests exists. It is a beat note.
No disagreement with others who point out there nothing new here.
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The paper though does not grasp, that commercial pressures were at play. The CD format was carefully chosen for its time duration which then resulted in its present physical size. The physical size similarly was commercial in its intent, rather than exploring a slightly larger disc format and extending audio frequency.
The time duration in particular was apparently consultation by Sony/Philips with Herbert von Karajan as to what available time was needed for a piece of classical music.
https://www.snopes.com/fact-check/roll-over-beethoven/
Resulting in spirited individuals questioning the 20khz bandwidth
There's life above 20 kilohertz! A survey of musical instrument spectra to 102.4 kHz
http://wilson-benesch.com/reviews/Life_Beyond_20kHz_Blackmer_SVC_Sep-1998.pdf
The CD standard might have and could still reinvent itself, by allowing say 40khz audio bandwidth. We just have to compare CD, to a Denon DL103 LP cartridge
Technical Specification
Stylus: 16.5 μm diamond spherical tip.
Cantilever: Aluminum.
Frequency Response: 20 ~ 45 kHz.
If we can finally get off the commercial roundabout certain individuals and companies insist upon - limiting frequency to 20Khz , we hopefully with enough pressure ( more than a volcano perhaps needed ) might see Nyquist at 100khz and audio response to 45khz with 5Khz of filtering roominstead of present brickwall.
It is apparent the physical size is no longer a restriction as it was in the early 1980's
but the 20khz limitation depressingly remains.