Sample Rate

[OneZeroMusic]

Hey, I have the E-MU Tracker Pre external sound card and when I first connected the device to my computer ableton had the devices highest sample rate available (192kHz) and it is no longer accessible. Does anyone know how to correct this issue?

[mr.ergonomics]

when this question comes because you want to record in 192 khz for a better quality.... there is no benefit with 192 khz. only if you want to record a bat or a grasshopper.

[OneZeroMusic]

Actually, it provides a more accurate representation of the original signal, and while it may be overkill it does enhance the quality of higher frequency notes such as C5. As a simple example if you have a Sine wave with a frequency of 400Hz and a sample rate of 800Hz(the minimum sampling frequency to somewhat accurately reconstruct the signal), the signal will be sample at the troughs, inflection points and the peaks. This is a poor representation of a Sine wave, which is typically why people use frequencies that more than twice as high as our maximum audible frequency to the human ear for sampling. So if I want to produce a song that uses a lot of high frequency material and I want an extremely accurate representation of the signal, 192kHz is much more effective than 92. I take it by your comment you will only record a grasshopper or a bat that you actually have no idea how sampling frequencies work, in that case I would ask that you look into how something actually works before being condescending.

[Tone Deft]

face meets palm.

anyone else wanna handle this one?

[Winterpark]

Actually, it provides a more accurate representation of the original signal, and while it may be overkill it does enhance the quality of higher frequency notes such as C5. As a simple example if you have a Sine wave with a frequency of 400Hz and a sample rate of 800Hz(the minimum sampling frequency to somewhat accurately reconstruct the signal), the signal will be sample at the troughs, inflection points and the peaks. This is a poor representation of a Sine wave, which is typically why people use frequencies that more than twice as high as our maximum audible frequency to the human ear for sampling. So if I want to produce a song that uses a lot of high frequency material and I want an extremely accurate representation of the signal, 192kHz is much more effective than 92. I take it by your comment you will only record a grasshopper or a bat that you actually have no idea how sampling frequencies work, in that case I would ask that you look into how something actually works before being condescending.

I guess the questions you have to ask yourself if you want to insist at recording at 192k are...
how much disk space do you have?
how high can human hearing go?
what are you going to bounce it out at?

i'm sure there could be a bunch of psycho-acoustic stuff that can take place up there in the nether regions where bats and dolphins hear, but i think recording at 192k is a bit overkill...

[rcpunker]

[OneZeroMusic]

I guess the questions you have to ask yourself if you want to insist at recording at 192k are...
how much disk space do you have?
how high can human hearing go?
what are you going to bounce it out at?

i'm sure there could be a bunch of psycho-acoustic stuff that can take place up there in the nether regions where bats and dolphins hear, but i think recording at 192k is a bit overkill...

Oh my..it appears as though I didn't explain myself clear enough. This is a bad analogy but I think it will provide a better understanding. Imagine you have a repeating picture that is 10ft long (a picture of a log for instance). Now imagine that you have a device that only shows you a part of the photo, say once every 10 ft you'll see part of the photo. Based on this you will never see the full photo (sampling frequency equivalent to the frequency that we're sampling). Now imagine you can set the device to view the photo every 5 ft, you get to see more of the photo, but you still don't get to see a good majority of it (sampling frequency being 2x greater than the frequency being sampled). Now imagine you can set the device to see the photo every 1 ft, you get a pretty good idea of a lot of things that are in the photo at this point(sampling frequency being 10x the frequency being sampled). Now, instead of a log that is 10ft long, we have a sound that is 20kHz(approx the max range of the human ear), having a sample frequency of 192kHz is roughly the same as viewing the 10ft repeating picture every 1ft, allowing the software to more accurately reconstruct the sound. That so when it is played back, we can hear a better approximation of the original sound.

I have about 2 TB worth of HDD space, the human hearing range peaks at approximately 20kHZ(as mentioned above) and I'll probably bounce it out at that same sampling frequency and see how big the file is and adjust accordingly.

I hope this is more help in understanding how the sample frequency actually works.

Now does anyone know how to resolve my issue with this?

[Tone Deft]

the only reason to use a 192kHz sample rate is for lower audio latency.

your hearing does not go up to 20kHz, you don't know what your hearing is, you've never tested it. Live has a tone generator, run it up and down, you cannot hear 20kHz. not unless your 8 years old. you'll be surprised at how low your hearing cuts out, it's humbling.

pretty much everyone on this forum knows about Nyquist's sampling theory, go read it. your explanation is really awkward.

as for your question update to the latest driver.

if that doesn't work look at your computers sound settings, there could be some goofy setting there. maybe your card disables 192kHz when you use another feature like expanding the channel count. go poke around.

[OneZeroMusic]

I'm well versed with the Nyquist sampling theory(the people above seem to think sample frequency samples frequencies specifically in the range specified by the device and not at the specified rate, at least thats what I took from their response), and I know my explanation is awkward but its easier to visualize than the previous explanation.

With regards to maximum human hearing range, it expresses the point I'm trying to make even if it is with regards to a child. The hearing test with a tone generator sounds like a cool idea though, I'll try it out. Also I recall reading an article not too long ago that mentioned how sounds not in our audible range still have an effect on perception of sound. If you'd like I'll look for the article and post it.

I already tried poking around and didn't see any settings that have been changed from when the 192 option was available, which was 2 days ago. Any other suggestions?

[Winterpark]

I guess the questions you have to ask yourself if you want to insist at recording at 192k are...
how much disk space do you have?
how high can human hearing go?
what are you going to bounce it out at?

i'm sure there could be a bunch of psycho-acoustic stuff that can take place up there in the nether regions where bats and dolphins hear, but i think recording at 192k is a bit overkill...

Oh my..it appears as though I didn't explain myself clear enough. This is a bad analogy but I think it will provide a better understanding. Imagine you have a repeating picture that is 10ft long (a picture of a log for instance). Now imagine that you have a device that only shows you a part of the photo, say once every 10 ft you'll see part of the photo. Based on this you will never see the full photo (sampling frequency equivalent to the frequency that we're sampling). Now imagine you can set the device to view the photo every 5 ft, you get to see more of the photo, but you still don't get to see a good majority of it (sampling frequency being 2x greater than the frequency being sampled). Now imagine you can set the device to see the photo every 1 ft, you get a pretty good idea of a lot of things that are in the photo at this point(sampling frequency being 10x the frequency being sampled). Now, instead of a log that is 10ft long, we have a sound that is 20kHz(approx the max range of the human ear), having a sample frequency of 192kHz is roughly the same as viewing the 10ft repeating picture every 1ft, allowing the software to more accurately reconstruct the sound. That so when it is played back, we can hear a better approximation of the original sound.

I have about 2 TB worth of HDD space, the human hearing range peaks at approximately 20kHZ(as mentioned above) and I'll probably bounce it out at that same sampling frequency and see how big the file is and adjust accordingly.

I hope this is more help in understanding how the sample frequency actually works.

Now does anyone know how to resolve my issue with this?

I understand your explanation, but I've got a better explanation for you... (as i'm actually a music production teacher, who has to teach nyquist theory)

if your sample rate is 44100, then it's actually sampling 44100 times per second.... which you halve to take into consideration that you want to capture the representation of a full cycle. This gives you a magic number of 22050... so according to the nyquist theory, that means if you sample at 44100, theoretically, you are accurately recording sounds that are well above the range of human hearing.

so... 192k is actually sampling 192,000 times per second, which will give you an accurate picture of frequencies up to 88,000Hz, which is 4x greater than any audible frequency heard by humans. I get what you mean about the more snapshots, the more accurate the picture, it's just that i believe that a higher bit rate is more important here, because to use your analogy, every picture of the 'log' you are taking is of a greater quality... like taken with a 3 megapixel vs 10 megapixel camera.

and as i said, i'm not discounting any possible psycho-acoustic stuff that may or may not be occurring, but i'd add a qualification to that... you should check the frequency response of the speakers upon which you are playing back your music, because, i'm pretty sure that they aren't going to extend up to 88,000hz....

so i personally see no point in recording at 192, because my speakers won't be able to play back all that extra detailed top end, that I wouldn't be able to hear anyway with my 30-something year old ears that have played too many punk rock gigs, and if it was going to be released, it's most likely going to end up at 16/44100, or even worse as an mp3.

anyway... i have no solution to your problem, i just felt like i'd like to clarify my position, which is based on some years of experience.

good luck with your recording!

[OneZeroMusic]

I'm not placing importance on the maximum frequency on which you can sample, I'm placing importance upon the accuracy of the reconstruction of lower frequency signals. With a sampling frequency of 192kHz you sample your sound every 520.83 nanoseconds, as opposed once every 2.26757 microseconds with a frequency of 44.1kHz, so when you sample sounds that are in the audible range you have a more accurate reconstruction of the original signal. Theoretically it will never be the same because you would need an infinite sampling frequency.

With regards to your comment that two times the sampling frequency accurately records the sound, this is false. While sampling at twice the frequency is enough to reconstruct the sound being recorded, it is poor quality. Again, taking a Sine wave, lets say 100Hz, and a sampling frequency of 200. Because the sampling frequency is only twice the frequency of the Sine wave you only get the zero crossings and there would be no sound produced (since it isn't possible to produce a perfect Sine wave in nature without interference, this generally is not seen).

When you sample a recording you create a digital representation of the recording with the values between the digitalized points being approximated by connecting the points. So, when I record something in the 10kHz range with a sampling frequency of 192kHz I'll get approximately 19 digital values(not a lot, but a hell of a lot better than the 2 values you get with a sampling frequency only 2 times the actual frequency) that represent the analog on the same equivalent time scale. The remainder of the values(which is technically infinite because you can reduce the time scale down to whatever you want) are approximated by "connecting the dots" so to speak.

So, if you actually understand what I'm talking about you can see that I don't give a damn about high frequencies, I care about the accurate reconstruction of lower frequencies. I studied all of the mathematics required for this in about 12 of my university classes. I know what I'm talking about and it would be easier to explain with a piece of paper and a pencil.

For instance:

http://en.wikipedia.org/wiki/File:Signal_Sampling.png

This is a good photo representing what I'm talking about, if the value of T was larger (indicating a lower sampling frequency), there would be less discrete values and the reconstruction of the signal in that photo would not be as accurate.

[Akshara]

Guys, if he wants to record at a higher sample rate, for whatever reason, then allow him to do so and get off his back, geez. He asked a simple question about his audio interface.

It sounds like he is less concerned with the nyquist audible range issue than he is with capturing a very high resolution snapshot of the original acoustic waveform, with less stepping.

If I had the hardware and financial resources to record everything at 32-bit / 192khz, I certainly would.

To the OP... the first place I would look is with a conflict between the E-MU and the internal sound card. It may be as simple as changing which interface the OS sounds play through, or with disabling them; and on the extreme end, depending upon your hardware and OS, it may require disabling the internal sound card altogether. It may also help to trash the Preferences.cfg file, though that will reset all or your custom settings, so don't do it casually. I would also recommend contacting Ableton or E-MU directly, as this is a very specialized issue.

If you do continue to poll for user assistance around here and on other forums, then I recommend learning to let the stream of "don't use 192khz" posts that you are most certainly going to receive, no matter where you ask, to simply roll off your back. There is no need to prove anything to anyone, and you will never win in this debate. I've been there, and trust me, it doesn't lead anywhere good. That is, unless you actually want a fight, then explain away.

[OneZeroMusic]

Guys, if he wants to record at a higher sample rate, for whatever reason, then allow him to do so and get off his back, geez. He asked a simple question about his audio interface.

It sounds like he is less concerned with the nyquist audible range issue than he is with capturing a very high resolution snapshot of the original acoustic waveform, with less stepping.

If I had the hardware and financial resources to record everything at 32-bit / 192khz, I certainly would.

To the OP... the first place I would look is with a conflict between the E-MU and the internal sound card. It may be as simple as changing which interface the OS sounds play through, or with disabling them; and on the extreme end, depending upon your hardware and OS, it may require disabling the internal sound card altogether. It may also help to trash the Preferences.cfg file, though that will reset all or your custom settings, so don't do it casually. I would also recommend contacting Ableton or E-MU directly, as this is a very specialized issue.

If you do continue to poll for user assistance around here and on other forums, then I recommend learning to let the stream of "don't use 192khz" posts that you are most certainly going to receive, no matter where you ask, to simply roll off your back. There is no need to prove anything to anyone, and you will never win in this debate. I've been there, and trust me, it doesn't lead anywhere good. That is, unless you actually want a fight, then explain away.

Deleting the config file worked, thank you! haha finallyyyy, and good recommendation, it has been a headache re-explaining the same thing every time someone responds.

[kanuck]

For those of you not supporting 192khz sampling rate.. what bit rate and sampling rate are you guys for then?

[kanuck]

For those of you not supporting 192khz sampling rate.. what bit rate and sampling rate are you guys for then?