Yes, you can take shortcuts and pick up some information without a background in a subject, but it has its limits. At some point, you need to know the basics to be able to move ahead and even communicate accurately.
It's like trying to discuss more advanced math when you haven't taken Algebra. Without that foundation you can probably be explained some concepts, but it's just not going to work and you'll be asking some strange questions. As someone who's learning style is more top-down rather than bottom-up I can empathize, but sometimes there is no shortcut.
Retirement home?
Some of the folks in your self-described retirement home were designing 16 bit 3.5 MHz DAs in 1988 when you were still on the...relying on your mother for sustenance, let's say...lolol Even if my role was only to design the output filter.
Signed - not retired yet
Cheers!
Howie
Some of the folks in your self-described retirement home were designing 16 bit 3.5 MHz DAs in 1988 when you were still on the...relying on your mother for sustenance, let's say...lolol Even if my role was only to design the output filter.
Signed - not retired yet
Cheers!
Howie
🙂 😎
-RNM
I wonder what the average age here is. many are old enough to retire and some have even died while on this DIYaudio
When they drag me away for the last time, i'll just give a smile, cool look and thumbs up.
-Richard
Originally Posted by mountainman bob View Post
if I knew what I was talking about I wouldn’t be here...so I digress.
I only mentioned the slew rate thing because it kept popping up with digital brick wall filtering and how it’s tied to Nyquist limits etc.
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Actually, it does matter (SR) as you do not want the input signal Tr to be faster than what the amp input can handle. You dont want to drive the input into Slewing condition.
THx-RNMarsh
if I knew what I was talking about I wouldn’t be here...so I digress.
I only mentioned the slew rate thing because it kept popping up with digital brick wall filtering and how it’s tied to Nyquist limits etc.
------------------
Actually, it does matter (SR) as you do not want the input signal Tr to be faster than what the amp input can handle. You dont want to drive the input into Slewing condition.
THx-RNMarsh
In addition to Hhoyt's post, although the true NTSC rate was apparently 29,97 Hz the calculation was based on the EIAJ countries where the 30Hz black and white frame rate was used.
The countries using the PAL/SECAM system get another version with a different sampling rate (and the explicit marking on the front plate).
Therefore the NTSC version sampled at 44,056 kHz while the PAL/SECAM version used 44,1 kHz and at that time there was no easy way to share the digital between the two versions. You could't replay the tapes on the other system.
Unfortunately bispectral analysis (and the other variants) aren't the most intuitive analysis tools .....
Helps how? Apparently it's impossible to prove a negative, surely that doesn't mean it's also impossible to prove a positive? But since it appears to be quite difficult to prove hi-res helps, a little evidence will do for starters 😉
They are not and we are also probably short of a dimension to portray the results usefully. That is why the suggestion of dynamically filtering measures in the second-order time-frequency plane might offer a better way forward. Even if such filtered measures still turn out to be somewhat short of realising a measure that relates directly to our perception, their visual inspection might yield the insight into audible phenomena that concerns many of the posters in this thread and others.
Assuming that the above was written by you, a few comments:
1) Our brains do not exceed the "uncertainty principle" but the "Fourier uncertainty principle".
As Scott already commented, Fourier analysis was never meant to replicate our hearing system.
2) A reference is made to Ohm's acoustic law.
This was a first attempt to understand how we perceive sound.
His opinion was that the sound we hear is independent of the phase relation between frequencies.
This was later proven to be wrong by Seebeck.
3) You refer to bispectra, seemingly because you have some knowledge in this area.
It might be interesting if you could make bispectral images of a Cymbal before and after Brick Wall filtering.
Hans
Heading off in a slightly different direction, but based on some posts from yesterday I was wondering if anyone actively hunts out recordings that are in surround sound and listens to them? I don't have space for a surround setup at the moment, but it's on my wish list for when I get a larger listening space.
I know I put soundfield illusion above other parmeters in my personal desires for an audio system but just wondered if anyone else had explored life beyond 2 channels.
I know I put soundfield illusion above other parmeters in my personal desires for an audio system but just wondered if anyone else had explored life beyond 2 channels.
Indeed it was.
Thank you 🙂
I never meant to imply otherwise, just indicate that there is an implicit model of the ear as a second-order spectral analyser in discussing results in second-order measures.
Again I never meant to contradict this, but instead to point out that the model of the ear and brain as a second-order spectral (magnitude) analyser has its limitations - as you rightly reference. My intention was to suggest that the audible characteristics due to the phase response of filters is one example where diverging from more conventional second-order analyses might be of benefit.
Indeed it would! There is another thread on this forum where its application at low frequencies might also be insightful, possibly many others too... But as I suggested earlier, portraying a bispectral plane in time is not an easy task in two-dimensions. Instead we might be left with having to dynamically filter second-order analyses in the time-frequency plane in the hope we could identify visually the artefacts that correspond to what we hear - or maybe even their absence when we just convince ourselves we hear something 🙂
It was conditonal on TNT's implicitely given assumption (i.e. that sampling at Fs at 192 kHz or even above) solves any problem that might exist. While that might be true - again under an assumption like that microphones are used that offer extended bandwidth - it will not help in this regard if not distributed in such a format that preserves the possible benefits.