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drmatt
2018-09-08, 16:29
Anyone got a sound processing plugin that can apply that 80s style spatial stereo sound expansion when the speakers are a bit too close together?


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drmatt
2018-09-13, 23:32
Guess not! Perhaps I should move my speakers a bit further apart...


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philippe_44
2018-09-13, 23:57
Guess not! Perhaps I should move my speakers a bit further apart...


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It’s complicated as you would need to fully decode the audio in LMS, apply the spacialiazer and the re-encode to an identical format

bpa
2018-09-14, 02:39
Years ago there was the inguzDSP plugin but I don't think anybody posted about spatial more about room correction.

Nowadays I'd expect the spatial or EQ stuff to be done in a player not in LMS and so would be on the audio side of a Squeezelite based Pi system.

Man in a van
2018-09-14, 03:00
Anyone got a sound processing plugin that can apply that 80s style spatial stereo sound expansion when the speakers are a bit too close together?


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Just pop a Boom on a stand :):p:rolleyes: and turn the XL up to max!!

25619

ronnie

Paul Webster
2018-09-14, 03:21
How about using SoX to transcode with a LADSPA plugin.
There is one that is described like this:
Matrix Spatialiser (matrixSpatialiser, 1422)
A simple spatializer that lets you control the width of a stereo signal.
We convert it into a MS (mid/side) signal, manipulate the gain coefficients with a constant-power panning function, and reconvert to left/right stereo.
mid = (i_left + i_right) / 2
side = (i_left - i_right) / 2
width = (-pi/4)..0..(pi/4)
o_left = mid * cos(width + pi/4) o_right = side * sin(width + pi/4)
shifted by pi/4, so that 0 is neutral.
Width
0 is neutral (unmodified signal) + 128 is side only (=very wide) - 128 is mid only (=mono)

http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html#tth_sEc2.69

drmatt
2018-09-14, 08:03
Cunning plan..

Though I was thinking of the spatial stereo encoding systems that used to use phase encoding to enhance the stereo beyond the speakers themselves.

Is that what the Boom does? Knew I wanted one. Now I know why...


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toby10
2018-09-15, 04:34
StereoXL better explained and experiences (post 7 and beyond)
https://forums.slimdevices.com/showthread.php?66609-Just-unpack-my-new-Boom-and-first-issue!&highlight=enhancer


StereoXL explained (from SB Boom white paper)

StereoXL Technology
StereoXL™ is a proprietary stereo expansion technology developed by Logitech audio
engineers. It provides a significantly enhanced stereo sound field, expanding the sound stage
beyond the physical extents of the speakers themselves.

I have always been wary of this type of processing for fear that it would wreck the audio quality
in order to achieve the effect of stereo widening. However, once the engineers from the
Logitech Audio business unit helped implement StereoXL in the Squeezebox Boom, the results
were very surprising. The audio quality wasn’t diminished at all, but the sound seems to come
from everywhere.

That said it can be overdone, and the quality depends on the track used and the encoding used.
In order to allow for varying user preferences, and track encodings there are 3 settings for
StereoXL. The best one is typically in the middle (medium).