feature request

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paulwi1008
Posts: 10
Joined: Sat Nov 11, 2006 9:19 pm

feature request

Post by paulwi1008 »

Is it possible to get 88,200 kHz sampling rate provided as an option on the pull-down menu when setting up a new recording session?

Sarah k Alawami

feature request

Post by Sarah k Alawami »

Just for curiosity sake what are you doing that requires such a high sampling rate? We'll see what the dev says regarding your suggestion and good luck.
On Oct 11, 2013, at 1:40 AM, paulwi1008 <forum2mail@hairersoft.com> wrote:
Is it possible to get 88,200 kHz sampling rate provided as an option on the pull-down menu when setting up a new recording session?




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paulwi1008
Posts: 10
Joined: Sat Nov 11, 2006 9:19 pm

Post by paulwi1008 »

It's a very esoteric project that would take a while to explain and still wouldn't make much sense to most readers. Let's just say that it is serving a purpose more scientific than entertaining or aesthetic.

For what it's worth, there's a typo in my original question. It should have read "88.2 kHz." Martin has 96 kHz as an option, but not 88.2.

JEGG
Posts: 122
Joined: Sat Feb 24, 2007 6:33 pm

High Sample Rates

Post by JEGG »

Since the subject of high sample rates surfaces now and again:

1. Sample Rate options displayed: Certain hardware doesn't necessarily offer every "standard" SR choice. So a device may offer 96k but not 88.2, or it may offer the rate but due to the way it is reported the software doesn't see certain rates.

2. Why high sample rates:

A. As mentioned their are applications ranging from scientific research to sound design which depend on such rates, often with the intent of modifying material after the fact my modifying sample rate. For example, capturing sounds far above human hearing. (Yes, there are plenty of microphones for scientific and other use which offer such response.)

B. Many plugins behave quite differently with higher SR. In fact, many plugins sample up "under the hood" and sample back down. For a very obvious demonstration, please download the free plugin Voxengo "Overtone GEQ." This is an interesting EQ, and the user can select the the amount of oversampling. Try using a 44.1 file of wide band music material, or perhaps something off a CD. While using the EQ, select different amounts of over-sampling and the effect (pun not intended) is quite dramatic. This is one reason why some engineers 1) run entire projects at higher SR rates, and/or 2) upsample existing files to process before down sampling again. Higher sampling rates offer more points to reference when constructing an analogue waveform, which has advantages that extend even to metering.

C. Using a high sample rate essentially takes the (often undesirable) low pass Nyquist filter out of the question - or at least pushes it very far upwards. A Nyquist filter is the "brick wall" filter designed to prevent aliasing. Most gear runs at higher SR's, and down samples to the more usual 44.1 etc. Often said gear doesn't have great Nyquist filters - and the same is true of SRC in software appications. Most SRC software produces significant aliasing, which one hears as tonal shifts. The products of aliasing spread throughout the audible bandwidth.

Surprisingly, Nyquist filters can really effect of the low end (!) of a recording as well, because it can produce phase shifts across the audio bandwidth.

With a user selected quality controllable Nyquist filter (generally in another application), one can select slope, absolute cut off point, post vs pre ringing (as in "linear phase"), etc., and arrive at the ultimate SR by the user's own choosing.

So these are a few reasons why some people use higher sampling rates.
Last edited by JEGG on Mon May 26, 2014 4:47 pm, edited 7 times in total.

JEGG
Posts: 122
Joined: Sat Feb 24, 2007 6:33 pm

Duplicate post, sorry

Post by JEGG »

duplicate, sorry

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