Mid/Side Dynamics & Filtering with the L-1 Discrete MidSide

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klstay
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Mid/Side Dynamics & Filtering with the L-1 Discrete MidSide

Post by klstay » Tue Apr 06, 2021 7:58 pm

My journey into stereo and mid/side processing is in its infancy. (Other than the generic inverted modulation into a 2nd end of chain VCA or simple bass ducking or similar) As part of that I have this module from L-1 on my roadmap. Could someone familiar with this module (maybe even Alex himself!) perhaps clarify/verify a few things?

1. Is the SDCH input indeed a gate/env CV to trigger the A/R envelope on the unit? (Seems evident, just want to be certain)
2. When set to MIDSIDE mode instead of (DUAL MONO or STEREO) does the module "split" the patched stereo signal to mid and side then process the mid dynamics & optional filtering on the "left side" and the same for the side on the "right side" then recombine to stereo then to OUT 1 and OUT 2? (This again seems evident, just want to be certain on this as well)

For more "adventurous" mid/side filtering my initial thoughts are to use the WORNG mid/side module into a Fumana or similar then back to the WORNG or a pair of Boss Bow Twos for odd and even then to the WORNG. (Also the inverse order of that) Folding and more straightforward filtering is also planned.

Any helpful comments/feedback/guidance in this is greatly appreciated.

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Stab Frenzy
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Re: Mid/Side Dynamics & Filtering with the L-1 Discrete MidSide

Post by Stab Frenzy » Wed Apr 07, 2021 8:45 pm

This is a stereo compressor, mid side is just one of the modes it operates in. It’s a bit different to the LRMSMSLR which is just a converter that makes stereo into MS and then back, letting you process however you want in between.

Stereo/dual mono compressors can work in three modes:
Dual mono mode, where the left and right signals are compressed individually. This doesn’t work too well because if you have a loud signal on the left channel only the left side will reduce in volume while the right doesn’t, which will skew your stereo image to the right.
Stereo mode, where the two compressor channels are controlled by a sidechain which is both the left and right mixed together, meaning the stereo image will be stable.
Mid/side mode, where the stereo signal is converted to mid and side, then those two signals are compressed separately and then recombined to stereo afterwards. This means the gain and response of the two compressors used doesn’t have to be perfectly matched, and lets you also do things like high pass the side signal to centre low frequencies, and manipulate the width of the stereo image by adding more or less of the side signal. Doing it this way is the way you would compress when cutting vinyl masters or compressing an FM stereo radio signal. It gives you more control but is more complicated.

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klstay
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Re: Mid/Side Dynamics & Filtering with the L-1 Discrete MidSide

Post by klstay » Wed Apr 07, 2021 9:40 pm

Stab Frenzy wrote:
Wed Apr 07, 2021 8:45 pm
Mid/side mode...
Thank you for taking the time to explain this so well; I was really hoping either you and/or Alex would do so.

There is really a fair bit to learn (and plan) here. From your explanation this module is now a "must have" for me; likewise your mid/side module.

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