Mid/Side encoder, splitter? Any project, schematics?

[Olegarich]

Hey Diy Family,

I've been thinking about mastering compressor that would give me control of Mid and Side. Let say I'm gonna build two GSSL Compressors in one rack. I would like that one would be for the Mid and other one for the Side. There are some plugins that have this ability and are used by mastering engineers. So I wonder is there any schematics or projects, that gets Left and Right and makes it Mid/Side??? Oh and how you proper call that thing? encoder? Mid/Side Splitter??

Thanks

 

[Martin Griffith]

You could start here http://www.ka-electronics.com/kaelectronics/MS-II_Matrix/MS-II_Matrix.htm I also call it sum and difference, or just MS

 

[L´Andratté]

It´s called m/s encoder (r/l to m/s) or m/s decoder (m/s to r/l). But it´s both the same process, the same
circuit repeated.
There´s a passive solution and if you are prepared to pay at least $300 for transformers you can continue down that road. Iirc that´s done on the Fairchild compressor.
There´s an active solution comprising of a couple of jellybean components, that is maybe even much
better/linear performance than passive.  I think there´s a writeup on ESP/Rod Elliot´s site.
There´s also the that-chip variant from ProAudioDesignForum.(EDIT: that´s the one linked above)

 

[Martin Griffith]

I think there´s a writeup on ESP/Rod Elliot´s site.

I tried to find it as well, but Rod Elliot doesn't seem to have a search engine on his site, so I gave up and posted Wayne Kirkwood's glorious effort

 

[TwentyTrees]

Yep, Wayne Kirkwood’s MS matrix (encoder / decoder) is the bizness! Great design.

Funnily enough, Gustav has an MS-equipped two channel SSL-style VCA compressor kit - if that’s your end goal then this might be one route there: https://pcbgrinder.com/index.php?route=product/product&path=59_61&product_id=65

 

[gridcurrent]

from Neumann:

 

[ruairioflaherty]

There are some plugins that have this ability and are used by mastering engineers.

Used by some mastering engineers, others like me would wonder why in the world anyone would do that! And yes, I've tried it more than once, in analog and digital.

 

[mutterd]

Here is the Transformer/Passive method (similar to Gridcurrents Neumann write up) as presented by Jensen.

You could do this, in theory, with any line level, 600Ω, 1:1 transformer with split primary and secondaries, aside from the Jensen mentioned on the application note, there are a million options...

just off the top of my head, and in no particular order:

UTC A20
Triad HS66, HS56, a67j, a61j
Stancor WS-30
WE 111C
Hammond 804, 850G
Lundhal 1527

This is in no way a complete list - I have experience with the Hammond 804's and its a good option as it will drive a 10KΩ input without any additional loading necessary, zobel or otherwise.

If you want a level control you can put a pot across pin 2 and 3 on the input side and and feed the tops of the transformer primary from the wipers.

Timothy

 

[john12ax7]

Used by some mastering engineers, others like me would wonder why in the world anyone would do that! And yes, I've tried it more than once, in analog and digital.

Does this mean you don't specifically like M/S plugins?  Or does it mean you don't like M/S processing at all,  in any form?

 

[ruairioflaherty]

Does this mean you don't specifically like M/S plugins?  Or does it mean you don't like M/S processing at all,  in any form?

I was referring to MS compression in particular which baffles me, I have never had it work.

MS EQ I used for many years in both analog and digital domains until I started to learn the pitfalls, specifically how it damages the stereo image.  Once I heard that I could not unhear it and I went from using some form of MS EQ on almost every master to using maybe once every few months. 

It's a powerful tool and if you concentrate on what you "fix" it can be very enticing but once I got good enough monitoring and took a step back the damage it was doing was not worth the cost.

I generally prefer digital when I want to do MS and in the current room I work in we don't actually have the means to do analog MS EQ, nor do I miss it.

MS de-essing is another popular tool and with seemingly good logic behind it but even when I was a fan of MS I found that with a good enough De-esser MS was not required and again caused weirdness I'd rather avoid.

 

[guavatone]

You don’t NEED a plug-in to do MS. just make your own busing matrix.

Wayne does top notch stuff.

 

[gyraf]

from Neumann:

Look at that passive microphone matrix in page 1 - and then look at it again...

If four resistors was ever used for complex work, this is it 

This is where we got one of the key ideas for our G24 passive/aggressive compressor

Jakob E.

 

[mrclunk]

I was referring to MS compression in particular which baffles me, I have never had it work.

off topic but is MS EQ/comp ever used when mastering for Vinyl, to keep low end centred?

 

[Script]

off topic but is MS EQ/comp ever used when mastering for Vinyl, to keep low end centred?

Could use an elliptic filter for that. Might have to make up for loss in level though, if there is any.

 

[5v333]

Look at that passive microphone matrix in page 1 - and then look at it again...

If four resistors was ever used for complex work, this is it 

This is where we got one of the key ideas for our G24 passive/aggressive compressor

Jakob E.

simple passive circuits are super cool stuff!

ill have to look at that circuit again many times!


attached is my fantasy of a balanced passive enc/dec.

 

[emrr]

Look at that passive microphone matrix in page 1 - and then look at it again...

If four resistors was ever used for complex work, this is it 

This is where we got one of the key ideas for our G24 passive/aggressive compressor

Jakob E.

Build ya a bridge!

 

[Gold]

In the last couple of years super wide mixes have become all the rage. There are a lot of mixes where the lead vocal will be doubled and hard panned. It’s hard to grab that with a standard compressor. I’ve used M/S compression more often lately.

 

[Script]

Could be wrong, but me thinks that low bass sometimes gets more stereo these days too. Unconceivable in the age of vinyl. Must be an influence from the home-recording community.

 

[sahib]

...........So I wonder is there any schematics or projects, that gets Left and Right and makes it Mid/Side...……….

All in one.

https://groupdiy.com/index.php?topic=62527.msg792413#msg792413

 

[emrr]

I remember a guy who did a few songs on a record, I did a few, and the mixes he submitted for mastering had bass miked and DI'd, and hard-panned.  Out of polarity from one another.  Mastering guy giggled, and said "tell him to redo it". 

I put bass on a record for a client recently, and one effect they liked was a stereo side-to-side flanger.  Fine and good, but not for low 'E' going to vinyl I don't think.  I did put that track through a mid-side EQ and made the  bass mono below something like 120, still gave the desired effect without the potential problems. 

I can see what Paul says about hard panned lead vocals being a tough problem with a stereo compressor, especially if they are loosely synced.