With some of your favorites, that closely approaches a lawsuit.
All good fortune,
Chris
If you did not start with 20KHz BW and from that what the minimum sampling rate would be (NyQ...) ....
Instead, you started with what sampling rate is needed for a music signal (not a CW signal) and that might be the sampling needed for a one shot real time capture (which is more realistic than CW).
Roughly, 20KHz = 50 usec and so sample that 10 times or 5 usec sampling rate.
Then apply that as Nyq and get your BW and filters.
No laws broken just more accurate sounding results. IMO.
Thx-RNMarsh
Instead, you started with what sampling rate is needed for a music signal (not a CW signal) and that might be the sampling needed for a one shot real time capture (which is more realistic than CW).
Roughly, 20KHz = 50 usec and so sample that 10 times or 5 usec sampling rate.
Then apply that as Nyq and get your BW and filters.
No laws broken just more accurate sounding results. IMO.
Thx-RNMarsh
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It is amazing how he holds onto preconceived notions. Even with his own results staring him in the face, he refuses. He reminds me of the writer of the play used in "the producers", yelling at the audience..
It would be amazing if he tossed the attitude and actually worked the problem.
Things like doubling the exponential rise, carving to flattop using a cos(1.5k) to keep sidebands below 19.5k, mirroring that. All to remove the Gibbs at the slope discontinuity, and see precisely the impact slope of the modulation has on sideband extension. Alas, the 1/x time dependent frequency domain slope will remain forever lost to him..
Luckily, there are lurkers here who do understand this. I wish them well.
I wait with baited breath him accusing me of gibberish..the last defense.
And you, you troublemaker...😉
Jn
scottjoplin - no, they didnt provide a young teenager with an actual whip!
This device appeared to be two long pieces with a flat side on each and a hinge at one end. When the kid closed it quickly, would make the 'snap' sound from the two flat parts colliding. It's called a "slapstick" from a quick Google...
This device appeared to be two long pieces with a flat side on each and a hinge at one end. When the kid closed it quickly, would make the 'snap' sound from the two flat parts colliding. It's called a "slapstick" from a quick Google...
You really don't understand this, do you?
I am quite shocked..
The slope of the exponential defines the width of the exponential spectra. And as the slope increases, the spectra widens. An exponential modulation presents a sideband which changes with the slope, a time dependency. That is why I asked you to mirror the exponential modulation.
Had you understood, you would have also realized that there is a slope discontinuity where the flattop begins and where it ends. Had you realized that,you could have simply included a slope transition using a cos(1.5k) to remove that discontinuity from the Gibbs excitation. Leaving only the indicator of the exponential slope forcing the sideband over Fs within the Gibbs plot.
I can always hope you learn this, but alas, you obviously won't even think about it.
Thankfully, I have no skin in this game.
Make no mistake...I offered to create these waveforms and provide them, needing only the sampling rate other than the 1Mhz rate I created. All that someone else had to do was convert from excel to whatever file desired.
Jn
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HP: it dawns on me that you are talking about how the slope isn't the cause off the Gibbs reaction, but rather the abrupt start. I already stated that, and that was the reason I mentioned the time mirrored exponential.
You then created that time mirrored exponential, then argued using a point which is not valid for your last sim.
Your verbage is out of sync with your sims, why so?
I certainly understand your lack of understanding of the exponential slope vs sideband width as a time dependent function, as I too was simply taught the FFT energy plot..the profs at that time never taught that the plot was an integral and did not display the time dependence of an exponential modulation on the sidebands. That understanding comes with (pardon the pun)....time.
What I really do not understand, is that you previously mentioned that you believe cables have a sonic difference which is not explained by R,L, and C.
While I actually concur, my consternation is that nobody here called you on that statement..
Cheers, Jn
You then created that time mirrored exponential, then argued using a point which is not valid for your last sim.
Your verbage is out of sync with your sims, why so?
I certainly understand your lack of understanding of the exponential slope vs sideband width as a time dependent function, as I too was simply taught the FFT energy plot..the profs at that time never taught that the plot was an integral and did not display the time dependence of an exponential modulation on the sidebands. That understanding comes with (pardon the pun)....time.
What I really do not understand, is that you previously mentioned that you believe cables have a sonic difference which is not explained by R,L, and C.
While I actually concur, my consternation is that nobody here called you on that statement..
Cheers, Jn
With luck, those actually working with hi res will use the additional information to inform their tests. I am totally amazed that some will actually record hi res using low bandwidth microphones...what's the point?
Scott first developed the diff Gibbs envelope as a metric on seeing anything that exceeds Fs, Hans has taken it significantly further. These tests are significant achievements with respect to actually determining if musical instruments or content have the capability of exceeding CD Fs, so can be instrumental (pun intended) in establishing the need or lack of need, of microphone BW to fully support any instrument.
Should any hi res developer wish to further this train of engineering, I would recommend they contact either Scott or Hans for assistance in development of this metric. I can help with the theory, but I am not able to work for others. What arrangements either of them would make with third parties is not my worry.
Jn
Frankly, I don't give a dam* JN. Let's talk about real problems, engineering problems, with regard to the need for extended bandwidth of digital, and how we can best implement it.
Richard, I am not exactly following what you are saying, but I am sure that I have the essence of it. Don't let them criticize you, and have you take it to heart. We need you here.
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I am afraid you will have to explain yourself.
Did you think I was criticizing Richard?
Jn
Well, I actually do understand him.
I believe 40 kHz is sufficient, in agreement with you. And I present an actual engineering reason for such a recommendation.
I do question the need for 5 uSec sampling. In my work, I will tend to measure 3 orders of magnitude better than need where I can, but for cyclic waveforms believe a factor of ten is sufficient to reconstruct amplitude and phase in light of modulation envelopes.
That said, the interchannel timing accuracy of 5 uSec for localization is a big unknown, as well as what the actual entity keyed on for that 5 uSec is. Imaging is still a big unknown.
Ah, overlap posts..
If you have followed and understand my posts on modulation envelopes, you will know who I was directing concern over.
If you wish, I can easily detail my understandings to any of your fellow comrades. If they wish to persue, great. Offline would present less noise as it were.
Jn
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Apparently, to get REAL(uncompromised) 40KHz BW it takes 192K MINIMUM (5us). I agree with this.
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An analog to this in amateur radio is: while switching a CW carrier on and off, as the rise and fall times increase in slope (ΔV/ΔT) the width of the CW carrier increases proportionally. I find this link to be a good description of the concept: An Intutitive Explainaion of CW Bandwidth
Or did I miss your point John...?
Cheers & 73,
Howie / WA4PSC
Starting with sampling of single shot/real time event [instead of assuming CW signals], and the resolution desired will then derive the BW and filter needed et al.
THx-RNMarsh
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I listened to the Who's Quadrophenia today. Lots of strong cymbal crashes throughout by drummer Keith Moon, who I read was back to his preferred playing style.
No idea how the drums were recorded; mics, bandwidth, etc. But lots and lots of fast attack/decay envelopes in that one!
No idea how the drums were recorded; mics, bandwidth, etc. But lots and lots of fast attack/decay envelopes in that one!