Do we have this in plug-in land?

[Cooker]

Check figure 7;

https://studylib.net/doc/18510796/stere ... -technique

[Max M.]

Many descent parametric EQs allow you to adjust Mid/Side channels. Beside there're tens of dedicated "stereo imaging" plugins doing similar things (in infinite variations). Though none (I think) use the fig-7-like algorithm since in digital domain we have much more efficient/precise algorithms for that kind of processing.
Start with searching the KVR product database for "stereo imaging" and related tags (also read the tech. info for popular EQs).

[Cooker]

Many descent parametric EQs allow you to adjust Mid/Side channels. Beside there're tens of dedicated "stereo imaging" plugins doing similar things (in infinite variations). Though none (I think) use the fig-7-like algorithm since in digital domain we have much more efficient/precise algorithms for that kind of processing.
Start with searching the KVR product database for "stereo imaging" and related tags (also read the tech. info for popular EQs).

From page 6; When one now re-inserts the graphic equaliser into the feedback path (Fig7) itscentral unity gain settings will again give normal stereo, however, boosting any frequency band on the equaliser (equally in both equaliser channels) widens the stereo image in that band, and cutting it narrows the stereo in that band.

I did make a search and found nothing that can do that, at-least the way I understand whats written cause its advanced for me as a user (I'm not a developer).

[mike_the_ranger]

Boosting/cutting the side signal with a m/s eq like FabFilter proq does exactly this. it widens or narrows the stereo image in that band.

[Cooker]

Boosting/cutting the side signal with a m/s eq like FabFilter proq does exactly this. it widens or narrows the stereo image in that band.

Thats figure 2 on the paper

[mike_the_ranger]

Boosting/cutting the side signal with a m/s eq like FabFilter proq does exactly this. it widens or narrows the stereo image in that band.

Thats figure 2 on the paper

My fault, didn't even read the paper, just judged by the things you wrote But figure 7 seems like something you could achieve by routing. Have you tried building it in your daw to see how it might sound?

[Max M.]

its advanced for me as a user (I'm not a developer).

I think I'd just suggest to find some introductory tutorials on "Mid/Side Processing" (in general) just to get some basic ideas (so you'd also have more keywords/phrases/features to look for). E.g. adjusting the "Mid/Side" channels with an (whatever) EQ is exactly what "widens the stereo image in (whatever) band, and cutting it narrows the stereo in (whatever) band".

Either way here're just a few random examples (in no particular order and with no intention to push a specific plugin or a manufacturer):
https://www.kvraudio.com/product/pro-q-2-by-fabfilter
https://www.kvraudio.com/product/multib ... y-bitsonic
https://www.kvraudio.com/product/curveeq-by-voxengo
https://www.kvraudio.com/product/midside-by-goodhertz
https://www.kvraudio.com/product/mstere ... production
https://www.kvraudio.com/product/m-s-eq-by-ourafilmes
etc. and so on.

---
P.S. Aside of above just don't expect to find exactly the same description of the algorithms behind the plugins (first of all because plugin manuals/intros rarely get into internal algorithm details, and second what was thought as a neat optimization for a minimalistic analog circuit in 80s is in fact an dirty anti-optimization by various means today...). Yet again forget about the exact words in the paper and start with reading about "Mid/Side Processing" in general.

[Cooker]

Boosting/cutting the side signal with a m/s eq like FabFilter proq does exactly this. it widens or narrows the stereo image in that band.

Thats figure 2 on the paper

My fault, didn't even read the paper, just judged by the things you wrote But figure 7 seems like something you could achieve by routing. Have you tried building it in your daw to see how it might sound?

Thats ok. And no cause I don't think I can properly as I've never been into such paper reading/routing. As said I'm just a user, I need GUI

Its a long story how I found this pdf although I can hardly understand the advanced sections. But I believe its a mastering tool/technique thats hasn't been released as a plug-in yet so wanted to post here to be sure (if it has anyone, let me know) and inform developers.

[Max M.]

But I believe its a mastering tool/technique thats hasn't been released as a plug-in yet

What's wrong with Fig.7 algorithm (for modern use - i.e. why you most likely won't find the exact implementation of this algorithm in a plugin)?
1. (Graphic EQs just suck, especially for this specific mastering task - but I'm lazy to get into details - I'll leave that point to be commented by someone else).
2. The algorithm pretends to preserve the overall "energy" ("preserve frequency balance.") in the band of interest by doing "a mirroring" adjustments in the Mid/Side channels (e.g. cut in Mid -> same boost in Side and vice-versa) . The problem is that such "mirrored" adjustment makes sense only when Mid and Side channels have nearly identical level/energy of a signal in the said band. Which is never true for real world sounds. Thus any adjustments will change the overall "perceived" tone anyway and it's actually more convenient to have separate control over Mid and Side channels to be able to do more fine grained adjustments / less dramatical distortion. E.g. if boosting a band in the Side or cutting the same band in the Mid both have similar but possibly differently (very depended on the nature of the sound you process) sounding effect of "increased stereo width", it goes quite weird to have both effects simultaneously where only one can do the trick. Either way there're plugins that do just that (no separate M/S adjustments).
3. The "feedback routing" is a neat optimization (to achieve the mirrored adjustments ) for the particular scheme in the analog domain, but for a digital plugin it's much more straight-forward to achieve the same by directly linking/syncing (by simple programmatic means) the settings of the two (or any other amount) EQ channels.

[Cooker]

But I believe its a mastering tool/technique thats hasn't been released as a plug-in yet

What's wrong with Fig.7 algorithm (for modern use - i.e. why you most likely won't find the exact implementation of this algorithm in a plugin)?
1. (Graphic EQs just suck, especially for this specific mastering task - but I'm lazy to get into details - I'll leave that point to be commented by someone else).
2. The algorithm pretends to preserve the overall "energy" ("preserve frequency balance.") in the band of interest by doing "a mirroring" adjustments in the Mid/Side channels (e.g. cut in Mid -> same boost in Side and vice-versa) . The problem is that such "mirrored" adjustment makes sense only when Mid and Side channels have nearly identical level/energy of a signal in the said band. Which is never true for real world sounds. Thus any adjustments will change the overall "perceived" tone anyway and it's actually more convenient to have separate control over Mid and Side channels to be able to do more fine grained adjustments / less dramatical distortion. E.g. if boosting a band in the Side or cutting the same band in the Mid both have similar but possibly differently (very depended on the nature of the sound you process) sounding effect of "increased stereo width", it goes quite weird to have both effects simultaneously where only one can do the trick. Either way there're plugins that do just that (no separate M/S adjustments).
3. The "feedback routing" is a neat optimization (to achieve the mirrored adjustments ) for the particular scheme in the analog domain, but for a digital plugin it's much more straight-forward to achieve the same by directly linking/syncing (by simple programmatic means) the settings of the two (or any other amount) EQ channels.

Bingo! I think I guessed right on what it does and now a reveal; this feature I believe is in the weiss eq1!

https://www.weiss.ch/products/eq1 (click main features, you'll see the pdf I shared hinted there at m/s mode).

Sometime ago a friend of mine received a master for his mix. The kick was boomy and was fixed (among other things), but just out of curiosity I opened an analyzer and measured both the mix and masters average response so to my surprise they seemed identical while sounding different.

When listened with an m/s tool, I noticed some of the kick was sent to the sides. I find it cool that one can preserve all the material of a mix rather than cut them out, using crossovers I'd guess wouldn't be as detailed.

The best I could do by google'ing was to find that PDF (because the mastering house had very few digital outboard), if there's something that can do this please let me know.

[Max M.]

I opened an analyzer and measured both the mix and masters average response so to my surprise they seemed identical while sounding different.

I hope the "average response" did not mean "average response of the whole song" (or actually anything longer than 2 seconds) - notice that for a long average I can get vastly different sounding thing having exactly the same graphical response simply by compressing (and cutting the level accordingly) some (or all of the) band(s). (Not counting that many analyzers by default show sort of L/R average thus potentially hiding stereo image information that may change a lot for the ears).
Either way, speaking of the boomy kick: I'd say the room for possible interpretations is quite large. For instance if the original mix kick was not present in the Side channel at all then no straight-forward M/S processing (like in the paper) could "send it to the sides". (The algorithms can only decrease/increase the level of already present signals - so if it was the similar algorithm the kick was already in the sides just not very audible and/or was too loud in the mid). Technically there're a lot of other algorithms (well, infinite combinations of infinite combinations of them) that could do something like this too so it impossible to guess w/o further investigation

In general, there're a few free plugins mentioned above so you can start experimenting with this (and other) stuff right now and see what you can get (starting with some basic like-one-instrument/drum-sounds of various edge-case stereo positions/spread-image - doing the processing and listening to all of the stereo/mid/side results to get to use to this often not so very intuitive concept).

[mystran]

Using IIR filters in mid-side situations, especially when it comes to mastering, will typically just cause a mess with the stereo image. Either you use naive filtering and end up with unpredictable phase-panning the where the two signal paths are out of phase (ie. basically anywhere you do filtering), or you use phase-coherent cross-over networks and get (typically lots of) all-pass phase-shift on everything smearing your transients (which is not always "bad thing" in the subjective sense, but it's likely not the type of thing that you should be doing when it comes to mastering).

In the modern day of digital production, if you just want to adjust the relative mid-side balance in a frequency dependent way, linear-phase FIR filters can give you that without any of the phase problems.

[Cooker]

Thanks for the replies, I think its best for now to wait for the single to be released (will take a while as some other productions are going on) then share soundclips cause I'm aware its very hard to talk about something thats not present (or even if what I hear is already available or not).

[No_Use]

if there's something that can do this please let me know.

As I read the schematic (I'm no expert in this though) you just need something that can create feedbacks loops and lets you insert FX in the loop.

OTOH Reaper, Usine, Late Replies, Mux...

edit:
and do crossover routing between the loops

[mystran]

if there's something that can do this please let me know.

As I read the schematic (I'm no expert in this though) you just need something that can create feedbacks loops and lets you insert FX in the loop.

OTOH Reaper, Usine, Late Replies, Mux...

edit:
and do crossover routing between the loops

You would need said loops to be "zero delay" so really you need the whole thing designed as a "zero delay filter" (which you can't really do in a "modular" way as it requires a global solver) for it to work correctly.

Otherwise the additional feedback delay will cause additional phase-shift will cause much worse problems than the phase-shifts from IIR filtering.