spbinns

I'm trying to listen to 3 different versions of an audio file (originally mixed at 96k/24), which are at 96/24, 48/24 and 44.1/16. I'm trying to see if there is a noticeable difference between the different conversions, but I need to make sure that I am listening to a certain file at te correct sample rate.

I know that I can set the samplerate using the 'adstatus sr' object (I can see my Digi 192's sample rate change), and can use sfplay~ to play each audio file, but I am a bit confused as to at what sample rate sfplay will play each of the audio files.

I guess what I'm asking is, is there are way to play the 44.1 file at 44.1, 48k file at 48k and 96k file at 96k all in the same patch( not all playing at the same time, but the ability to switch between the different files), so that I can switch between and compare the different audio rates.

I do hope this makes sence; I have spent quite a long time trying to get this to work, but there doesn't seem to be any difference in the listening tests - I am confident it is not down to bad equipment - am using Digi 192's and Genelec monitors - so am thinking I havn't made a correct max patch.

samplerates-in-max

I don't know why you would listen to an 'upsampled' audio file?

there difference that you will notice is the varying effect on your cpu's usage. you need to compare the same audio recorded at different rates, playing a 44.1 file back at 96 won't do anything, the additional data just isn't there.

I don't know why you would listen to an 'upsampled' audio file?
there difference that you will notice is the varying effect on your cpu's usage. you need to compare the same audio recorded at different rates, playing a 44.1 file back at 96 won't do anything, the additional data just isn't there.

> I'm trying to listen to 3 different versions of an audio file

> (originally mixed at 96k/24), which are at 96/24, 48/24 and 44.1/16.

> I'm trying to see if there is a noticeable difference between the

> different conversions, but I need to make sure that I am listening to

> a certain file at te correct sample rate.

Max will always convert it again to fit the set sampling rate. So choose 

the driver with the sampling rate you want to test or set the sampling 

Don't expect any audible differences, the most crucial part is 1. 

recording, and 2. processing. Higher sampling rates will have much less 

aliasing, and smoother analog filters on the input. Thats it.

Sample rate conversion is a science in itself, but nowadays done usually 

If you did the sample rate conversion in Protools it should be fine...

Stuart Binns schrieb:
> Hi everyone,
>
> I'm trying to listen to 3 different versions of an audio file
> (originally mixed at 96k/24), which are at 96/24, 48/24 and 44.1/16.
> I'm trying to see if there is a noticeable difference between the
> different conversions, but I need to make sure that I am listening to
> a certain file at te correct sample rate.

Max will always convert it again to fit the set sampling rate. So choose 
the driver with the sampling rate you want to test or set the sampling 
rate (depends on your interface)...

Don't expect any audible differences, the most crucial part is 1. 
recording, and 2. processing. Higher sampling rates will have much less 
aliasing, and smoother analog filters on the input. Thats it.

Sample rate conversion is a science in itself, but nowadays done usually 
quite well...

-- 
Stefan Tiedje------------x-------
--_____-----------|--------------
--(_|_ ----|-----|-----()-------
-- _|_)----|-----()--------------
----------()--------www.ccmix.com

I did the sample conversion in Pro Tools, and on conducting the test, I could notice a very small difference between the 44.1 and 48k files - the 48k seemed to be less 'harsh' in the middle frequencies; the 48k seemed to me to be a little bit smoother.

Thanks for all your input everyone - i really appreciate it.

What were you downsampling *from*? ISTM that you'd be more assured of 

good results going 96->48 / 88.2->44.1 than, say, 96->44.1.

I saw a page a few months ago where someone had attempted to measure the 

spectral artefacts left by SRC in various bits of software - it was 

surprising how variable things were. The upshot seemed to be that Peak 

and CoolEdit Pro / Audition did the best job.

> I did the sample conversion in Pro Tools, and on conducting the test,

> I could notice a very small difference between the 44.1 and 48k files

> - the 48k seemed to be less 'harsh' in the middle frequencies; the

> 48k seemed to me to be a little bit smoother.

> Thanks for all your input everyone - i really appreciate it.

What were you downsampling *from*? ISTM that you'd be more assured of 
good results going 96->48 / 88.2->44.1 than, say, 96->44.1.

I saw a page a few months ago where someone had attempted to measure the 
spectral artefacts left by SRC in various bits of software - it was 
surprising how variable things were. The upshot seemed to be that Peak 
and CoolEdit Pro / Audition did the best job.

Stuart Binns wrote:
>
> I did the sample conversion in Pro Tools, and on conducting the test,
> I could notice a very small difference between the 44.1 and 48k files
> - the 48k seemed to be less 'harsh' in the middle frequencies; the
> 48k seemed to me to be a little bit smoother.
>
> Thanks for all your input everyone - i really appreciate it.
>
>
>


>> I do hope this makes sence; I have spent quite a long time trying 

>> to get this to work, but there doesn't seem to be any difference 

>> in the listening tests - I am confident it is not down to bad 

>> equipment - am using Digi 192's and Genelec monitors - so am 

>> thinking I havn't made a correct max patch.

> it is quite hard to tell between 44 and 48 but if the 48 has ben 

> made from the 96 you should hear the difference with good speakers 

> with 192 it is another story; this often sounds worse than 96 (at e 

> least with motu/rme/digi without big ben)

A couple of years ago, I saw a presentation from a guy who was doing 

surround sound promotions sponsored by Tannoy. IIRC, he claimed 

there was a study done showing that it was almost impossible to tell 

the difference between material upsampled from 48kHZ to 96kHz and 

material recorded at 96 kHz. Curious to hear about your results once 

Higher frequency resolutions allow for better representations of both 

the waveform shape (reducing the squaring out of high frequencies 

near 22k) as well as the phase. Upsampling improves the 

representation of the waveform which reduces distortion, but 

presumably has less impact on phase? (there are still two possible 

phase positions for a hypothetical 22kHz wave, but now they are more 

As someone mentioned before, though, it can make a difference in 

>> I do hope this makes sence; I have spent quite a long time trying  
>> to get this to work, but there doesn't seem to be any difference  
>> in the listening tests - I am confident it is not down to bad  
>> equipment - am using Digi 192's and Genelec monitors - so am  
>> thinking I havn't made a correct max patch.
>>
>
> it is quite hard to tell between 44 and 48 but if the 48 has ben  
> made from the 96 you should hear the difference with good speakers  
> and converters.
> with 192 it is another story; this often sounds worse than 96 (at e  
> least with motu/rme/digi without big ben)
>

A couple of years ago, I saw a presentation from a guy who was doing  
surround sound promotions sponsored by Tannoy.  IIRC, he claimed  
there was a study done showing that it was almost impossible to tell  
the difference between material upsampled from 48kHZ to 96kHz and  
material recorded at 96 kHz.  Curious to hear about your results once  
you get it working.

Higher frequency resolutions allow for better representations of both  
the waveform shape (reducing the squaring out of high frequencies  
near 22k) as well as the phase.  Upsampling improves the  
representation of the waveform which reduces distortion, but  
presumably has less impact on phase?  (there are still two possible  
phase positions for a hypothetical 22kHz wave, but now they are more  
spread out)

As someone mentioned before, though, it can make a difference in  
processing with plugins.

> A couple of years ago, I saw a presentation from a guy who was doing 

> surround sound promotions sponsored by Tannoy. IIRC, he claimed there 

> was a study done showing that it was almost impossible to tell the 

> difference between material upsampled from 48kHZ to 96kHz and material 

> recorded at 96 kHz. Curious to hear about your results once you get it 

Never trust statistics you didn't fake yourself... If I can easily hear 

the difference, the study was maybe targeted at untrained ipod degraded 

Or they used high end converters which I would never be able to afford 

Peter McCulloch schrieb:
> A couple of years ago, I saw a presentation from a guy who was doing 
> surround sound promotions sponsored by Tannoy.  IIRC, he claimed there 
> was a study done showing that it was almost impossible to tell the 
> difference between material upsampled from 48kHZ to 96kHz and material 
> recorded at 96 kHz.  Curious to hear about your results once you get it 
> working.

Never trust statistics you didn't fake yourself... If I can easily hear 
the difference, the study was maybe targeted at untrained ipod degraded 
ears... ;-)
Or they used high end converters which I would never be able to afford 
in my whole lifetime...

There's a paper in JAES (Journal of the Acoustic Engineering Society) 

September 2007 that might be of interest:

E. Brad Meyer and David R. Moran: "Audibility of a CD-Standard A/D/A 

Loop Inserted into High-Resolution Audio Playback".

"Conventional wisdom asserts that the wider bandwidth and dynamic range 

of SACD and DVD-A make them of audibly higher quality than the CD 

format. A carefully controlled double-blind test with many experienced 

listeners showed no ability to hear any differences between formats. 

High-resolution audio discs were still judged to be of superior quality 

because sound engineers have more freedom to make them that way. There 

is no evidence that perceived quality has anything to do with additional 

The authors suggest that the reason why SACD and DVD-A recordings are 

generally perceived to sound better is not the improved quality of the 

digital format, but rather the difference in approach to the mastering 

process. These recordings are assumed to be listened to in a hifi 

setting, and the mastering is thorough, and using proper headroom. In 

contrast most (popular) recordings are increasingly compressed to death 

to fit in with the lofi listening situations resulting from modern 

playback devices being used in noisy environments (cars, iPods, etc.).

>> A couple of years ago, I saw a presentation from a guy who was doing 

>> surround sound promotions sponsored by Tannoy. IIRC, he claimed there 

>> was a study done showing that it was almost impossible to tell the 

>> difference between material upsampled from 48kHZ to 96kHz and material 

>> recorded at 96 kHz. Curious to hear about your results once you get 

> Never trust statistics you didn't fake yourself... If I can easily hear 

> the difference, the study was maybe targeted at untrained ipod degraded 

> Or they used high end converters which I would never be able to afford 

There's a paper in JAES (Journal of the Acoustic Engineering Society) 
September 2007 that might be of interest:

E. Brad Meyer and David R. Moran: "Audibility of a CD-Standard A/D/A 
Loop Inserted into High-Resolution Audio Playback".

"Conventional wisdom asserts that the wider bandwidth and dynamic range 
of SACD and DVD-A make them of audibly higher quality than the CD 
format. A carefully controlled double-blind test with many experienced 
listeners showed no ability to hear any differences between formats. 
High-resolution audio discs were still judged to be of superior quality 
because sound engineers have more freedom to make them that way. There 
is no evidence that perceived quality has anything to do with additional 
resolution or bandwidth."

The authors suggest that the reason why SACD and DVD-A recordings are 
generally perceived to sound better is not the improved quality of the 
digital format, but rather the difference in approach to the mastering 
process. These recordings are assumed to be listened to in a hifi 
setting, and the mastering is thorough, and using proper headroom. In 
contrast most (popular) recordings are increasingly compressed to death 
to fit in with the lofi listening situations resulting from modern 
playback devices being used in noisy environments (cars, iPods, etc.).

Stefan Tiedje wrote:
> Peter McCulloch schrieb:
>> A couple of years ago, I saw a presentation from a guy who was doing 
>> surround sound promotions sponsored by Tannoy.  IIRC, he claimed there 
>> was a study done showing that it was almost impossible to tell the 
>> difference between material upsampled from 48kHZ to 96kHz and material 
>> recorded at 96 kHz.  Curious to hear about your results once you get 
>> it working.
>
> Never trust statistics you didn't fake yourself... If I can easily hear 
> the difference, the study was maybe targeted at untrained ipod degraded 
> ears... ;-)
> Or they used high end converters which I would never be able to afford 
> in my whole lifetime...
>
> Stefan
>


Samplerates in max