Nebula

I've used one in FL Studio, found a free one on the net somewhere, but how do they work? I've been trying to find some documentation but with no avail. Has anyone built a stereo enhancement patch? Any help would be much appreciated. Thanks!

stereo-enhancement

According to 'Enhanced Sound - 22 Electronics Projects for the Audiophile',

by Richard Kaufman, a 'shuffler' was once a popular feature of many British

recording studios, and it's use was for enhancing the stereo image.

"The device adds the right and left channels, to give an M, or middle

signal, and subtracts one channel from the other to give an S, or side,

signal. A balance control allows one to attenuate either the M or S signal

without affecting the overall loudness level."

The same technique is used in M-S recording using a cardioid and

figure-eight mic; parallel the figure-eight's output into two channels,

phase-reverse one channel, and pan left and right. Add to the omni, which is

> I've used one in FL Studio, found a free one on the net somewhere, but how do

> they work? I've been trying to find some documentation but with no avail. Has

> anyone built a stereo enhancement patch? Any help would be much appreciated.

According to 'Enhanced Sound - 22 Electronics Projects for the Audiophile',
by Richard Kaufman, a 'shuffler' was once a popular feature of many British
recording studios, and it's use was for enhancing the stereo image.
"The device adds the right and left channels, to give an M, or middle
signal, and subtracts one channel from the other to give an S, or side,
signal. A balance control allows one to attenuate either the M or S signal
without affecting the overall loudness level."
 The same technique is used in M-S recording using a cardioid and
figure-eight mic; parallel the figure-eight's output into two channels,
phase-reverse one channel, and pan left and right. Add to the omni, which is
panned central.
cheers
Roger

>
> I've used one in FL Studio, found a free one on the net somewhere, but how do
> they work? I've been trying to find some documentation but with no avail. Has
> anyone built a stereo enhancement patch? Any help would be much appreciated.
> Thanks! 

Speaking of M-S encoding, I recently built this little example patch for doing L-R to M-S conversions. Lot's of stuff you can do to tweak things in M-S format before converting to L-R again.

There's one that I found in Logic or something that basically works on

the spectrum. You can take 4-8kHz and pan it to the left, with a

curve, or something like that. I can't really think of a non-FFT way

to do it, but it might be cool as an exaggerated effect, especially on

human speech--so that you isolate certain vowels in certain speakers,

There's one that I found in Logic or something that basically works on
the spectrum.  You can take 4-8kHz and pan it to the left, with a
curve, or something like that.  I can't really think of a non-FFT way
to do it, but it might be cool as an exaggerated effect, especially on
human speech--so that you isolate certain vowels in certain speakers,
for instance.  Someone run with this?
Andrew


Logic 8 also has a nice binaural panner, which can do a lot of fun things.

Also, though I the previous explanations were adequate, I once did a bit of planning to do something similar in msp. After a little bit of search, I found this thread in a dsp forum which might be useful-

http://www.dsprelated.com/showmessage/5649/1.php

Logic 8 also has a nice binaural panner, which can do a lot of fun things. 

http://www.dsprelated.com/showmessage/5649/1.php


the one i've seen at some mastering studio is: 

- take a stereo signal, split it into left and right and flip the phase and add back to the opposite sides (left to right, right to left) and play with the level (very quietly for the most part). the louder the flipped signals, the wider the stereo image. (also the louder the signals, they might mess up the sound in the center though) you can play with multiple eqs as well, i.e. adding multiple eqed flipped signals, so that you can widen the image in the desired frequency ranges.

the one i've seen at some mastering studio is: 
- take a stereo signal, split it into left and right and flip the phase and add back to the opposite sides (left to right, right to left) and play with the level (very quietly for the most part). the louder the flipped signals, the wider the stereo image. (also the louder the signals, they might mess up the sound in the center though) you can play with multiple eqs as well, i.e. adding multiple eqed flipped signals, so that you can widen the image in the desired frequency ranges.


flipping the phase would always result into some kind of mono incompatibility, depending on the degree of teh flip. not that this matters today very much, but actually technically it would alter your signal in a way, that it comb filters itself, when played back mono. you should watch the phase in the stereo field, in any case.

aside this the logic way of creating stereo signal splitting signal into 8-12 bands while panning alternate band to the extremes makes sense and is mono compatible as well.

flipping the phase would always result into some kind of mono incompatibility, depending on the degree of teh flip. not that this matters today very much, but actually technically it would alter your signal in a way, that it comb filters itself, when played back mono. you should watch the phase in the stereo field, in any case.
aside this the logic way of creating stereo signal splitting signal into 8-12 bands while panning alternate band to the extremes makes sense and is mono compatible as well.

Andrew, this looks awesome. Do you happen to have a 4.63 version of your MS patch? Or maybe you could supply some screenshots, so i coudl rebuild it? Would love to.

Another thing you can do is to EQ the file slightly differently. Then 

split the original and EQed files into left and right channels. Now 

mix the EQed version with the original with a little delay (from 40 

to 200 ms) while the left-right balance of the original and the EQed 

version are different (e.g. turn the volume of the left channel of 

the EQed version down and turn the volume of the right channel of the 

original copy down - by 1 or 2 dbs). This creates a kind of spectral 

movement in the stereo field and gives the impression of a deeper and 

On 12 Dec 2008, at 09:16, uhito kiyosue wrote:

> the one i've seen at some mastering studio is:

> - take a stereo signal, split it into left and right and flip the 

> phase and add back to the opposite sides (left to right, right to 

> left) and play with the level (very quietly for the most part). the 

> louder the flipped signals, the wider the stereo image. (also the 

> louder the signals, they might mess up the sound in the center 

> though) you can play with multiple eqs as well, i.e. adding 

> multiple eqed flipped signals, so that you can widen the image in 

Another thing you can do is to EQ the file slightly differently. Then  
split the original and EQed files into left and right channels. Now  
mix the EQed version with the original with a little delay (from 40  
to 200 ms) while the left-right balance of the original and the EQed  
version are different (e.g. turn the volume of the left channel of  
the EQed version down and turn the volume of the right channel of the  
original copy down - by 1 or 2 dbs). This creates a kind of spectral  
movement in the stereo field and gives the impression of a deeper and  
wider stereo image.

>
> the one i've seen at some mastering studio is:
> - take a stereo signal, split it into left and right and flip the  
> phase and add back to the opposite sides (left to right, right to  
> left) and play with the level (very quietly for the most part). the  
> louder the flipped signals, the wider the stereo image. (also the  
> louder the signals, they might mess up the sound in the center  
> though) you can play with multiple eqs as well, i.e. adding  
> multiple eqed flipped signals, so that you can widen the image in  
> the desired frequency ranges.
> --
> mesa.elech/tele


Strictly, shuffling is a frequency dependent technique that boosts lows 

in the side signal to give the impression of wider bass (below ~700 Hz 

we rely more heavily on inter-aural level differences for location, 

It's effectiveness is dependent on the way the sound was originally 

recorded, as different stereo miking techniques rely to different 

http://www.audiosignal.co.uk/Resources/Stereo_shuffling_A4.pdf

The trick he describes at the end with a 

channel-swapping-phase-inverting feedback chain is pretty effective if 

used in moderation (and AFAIK is similar in basis to Bob Katz's 

Another similar trick involves decorrelating left and right signals so 

that they are optimally out of phase at any given moment, which enhances 

Kendall, G. "The Decorrelation of Audio Signals and Its Impact on 

Spatial Imagery", Computer Music Journal, Vol. 19, No. 4. (Winter, 

I've not made an attempt at seriously implementing this (with modulating 

filters & all), but it seems to be prone to introducing pronounced 

phasiness on certain types of material. YMMV.

> According to 'Enhanced Sound - 22 Electronics Projects for the Audiophile',

> by Richard Kaufman, a 'shuffler' was once a popular feature of many British

> recording studios, and it's use was for enhancing the stereo image.

> "The device adds the right and left channels, to give an M, or middle

> signal, and subtracts one channel from the other to give an S, or side,

> signal. A balance control allows one to attenuate either the M or S signal

> without affecting the overall loudness level."

> The same technique is used in M-S recording using a cardioid and

> figure-eight mic; parallel the figure-eight's output into two channels,

> phase-reverse one channel, and pan left and right. Add to the omni, which is

>> I've used one in FL Studio, found a free one on the net somewhere, but how do

>> they work? I've been trying to find some documentation but with no avail. Has

>> anyone built a stereo enhancement patch? Any help would be much appreciated.

Strictly, shuffling is a frequency dependent technique that boosts lows 
in the side signal to give the impression of wider bass (below ~700 Hz 
we rely more heavily on inter-aural level differences for location, 
above that on phase difference).

It's effectiveness is dependent on the way the sound was originally 
recorded, as different stereo miking techniques rely to different 
extents on level and phase differences.

Here's a paper by Gerzon:
http://www.audiosignal.co.uk/Resources/Stereo_shuffling_A4.pdf

The trick he describes at the end with a 
channel-swapping-phase-inverting feedback chain is pretty effective if 
used in moderation (and AFAIK is similar in basis to Bob Katz's 
mystifyingly-patented K-stereo process).

Another similar trick involves decorrelating left and right signals so 
that they are optimally out of phase at any given moment, which enhances 
separation. See

Kendall, G. "The Decorrelation of Audio Signals and Its Impact on 
Spatial Imagery", Computer Music Journal, Vol. 19, No. 4. (Winter, 
1995), pp. 71-87.

I've not made an attempt at seriously implementing this (with modulating 
filters & all), but it seems to be prone to introducing pronounced 
phasiness on certain types of material. YMMV.

Roger Carruthers wrote:
> According to 'Enhanced Sound - 22 Electronics Projects for the Audiophile',
> by Richard Kaufman, a 'shuffler' was once a popular feature of many British
> recording studios, and it's use was for enhancing the stereo image.
> "The device adds the right and left channels, to give an M, or middle
> signal, and subtracts one channel from the other to give an S, or side,
> signal. A balance control allows one to attenuate either the M or S signal
> without affecting the overall loudness level."
>  The same technique is used in M-S recording using a cardioid and
> figure-eight mic; parallel the figure-eight's output into two channels,
> phase-reverse one channel, and pan left and right. Add to the omni, which is
> panned central.
> cheers
> Roger
>
>
> On 11/12/2008 19:40, "Nathan"  wrote:
>
>> I've used one in FL Studio, found a free one on the net somewhere, but how do
>> they work? I've been trying to find some documentation but with no avail. Has
>> anyone built a stereo enhancement patch? Any help would be much appreciated.
>> Thanks! 
>
>
>

Andrew and Roger, thanks for the enlightenment! I had never heard M-S processing. Very cool, opens up a lot of possibilities!

These are great tips, wish we had more threads like this.

It makes me realize how mastering is an art in it of itself.

These are great tips, wish we had more threads like this.
It makes me realize how mastering is an art in it of itself.


???Stereo Enhancement???