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Gear / Technical Help => Microphones & Setup => Topic started by: Nick's Picks on June 13, 2006, 04:50:52 PM

Title: Mid-Side tricks and technique
Post by: Nick's Picks on June 13, 2006, 04:50:52 PM
making sense of it all...in the New Stereo Soundbook.

I scaned these and thought they'd be good for general discussion here.

What these images are showing is the post matrix XY output of M-S input using various polar patterns in the first diagram, and various widths in the 2nd image.

In the first image, I find it interesting that normal M-S using a cardioid microphone outputs an XY signal as though you were running two hyper-cards.  Running an Omni results in in a near Healy Technique of opposing cards.  Making a + w/two figure of 8s produces crosed 8's at 90deg (blumlein).  I suppose one could guess that running a sub-card as the Mid channel would make a fatter XY signal, more like running a traditional set of cards coincidently.  Very cool.

And the illustration w/the image width (side gain) is also interesting.
Title: Re: Mid-Side tricks and technique
Post by: wboswell on June 13, 2006, 05:05:15 PM
wow.  That's easily the most interesting thing I've read on this site in years.

I never understood why an omni would be used as the mid, and now I understand.

Thanks!
Title: Re: Mid-Side tricks and technique
Post by: SonicSound on June 13, 2006, 06:11:21 PM
Thanks for the post +T

A little slow... why would you run bidirectionals m/s and not just blumlein if the result is blumlein?
Title: Re: Mid-Side tricks and technique
Post by: KLowe on June 13, 2006, 07:52:58 PM
Thank you for this.  I have been debating the ck94 cap for a long time.  One reason why I never bought it was cause I just didn't "get it".  This helps tremendously.
Thanks for the input.  T's to you.  (if they really mean anything....to anyone besides my troll)

Title: Re: Mid-Side tricks and technique
Post by: Nick's Picks on June 14, 2006, 07:10:31 AM
Thanks for the post +T

A little slow... why would you run bidirectionals m/s and not just blumlein if the result is blumlein?

if blumlein was my choice for and end result, I wouldn't bother w/the MS matrix to make one.
however, the added value of doing it that way would be to the ability to "tweak" it w/more forward or side signal in post.  Can't do that w/the straight up blumlein pair.
Title: Re: Mid-Side tricks and technique
Post by: BWolf on June 14, 2006, 11:07:47 AM
Nick,

Thanks for the scan.  Thats really helpful.  Always wonder what happens when I put a little more side or mid into the mix.  I'm looking at the bottom of the second scan where they explain the formula.  Can you scan the reference page so I can see it (7-1) or tell me where I can buy this book.  Seems like a great resource to have around.

Thanks
Brad
Title: Re: Mid-Side tricks and technique
Post by: WiFiJeff on June 14, 2006, 11:18:25 AM
Nick,

Thanks for the scan.  Thats really helpful.  Always wonder what happens when I put a little more side or mid into the mix.  I'm looking at the bottom of the second scan where they explain the formula.  Can you scan the reference page so I can see it (7-1) or tell me where I can buy this book.  Seems like a great resource to have around.

Thanks
Brad

I got my copy a few years ago from Posthorn Recording in NYC.  They also carry another really good book, Williams "Microphone Arrays for Stereo and Multichannel Sound Recording," which is volume 1 of a projected set, printed in Italy and not available anywhere else I've seen.

Jeff
Title: Re: Mid-Side tricks and technique
Post by: CQBert on June 14, 2006, 11:24:28 AM
Interesting...  I have run a couple or M/S configurations in the past couple of years >

Schoeps MK21H  / MK8 > VMS > 722

Neumann U89 > 722

With the 722 recordings I was recording 2 distinct channels and doing the mix in post.  It was amazing to see how much the 30 v 50 v 70 % mixes altered the sound.  Being able to see a diagram of what I was doing is very interesting and explains why I liked what I did with each recording.   The room had definite effects on how my final mix was decided on.

+T for the info and tips!!

CQBert
Title: Re: Mid-Side tricks and technique
Post by: Nick's Picks on June 14, 2006, 01:22:17 PM
The book is "the new stereo soundbook" by ron streicher and f. alton everest.  I bought my copy used on amazon a few years ago.
i'll see about scanning some more.
there is a cool section in there about the Soundfield, history of, how it works and the "ambesonic playback chamber" that is way, way cool.
Title: Re: Mid-Side tricks and technique
Post by: Gutbucket on June 14, 2006, 03:59:39 PM
Thanks for the post +T

A little slow... why would you run bidirectionals m/s and not just blumlein if the result is blumlein?

if blumlein was my choice for and end result, I wouldn't bother w/the MS matrix to make one.
however, the added value of doing it that way would be to the ability to "tweak" it w/more forward or side signal in post.  Can't do that w/the straight up blumlein pair.

You're correct about using M/S to "tweak" the stereo width, but.. (and it's not so widely known outside engineering circles) you CAN adjust ANY stereo L/R signal in post by first running your L/R source through a M/S matrix to derive sum & difference (M/S) signals, adjusting the M to S ratio, and finally running it back through the matrix again to sum back to L/R.  This is what some stereo tweaking plugins do behind the scenes, but you can do it the old fasioned way with a mixer, too.  Besides adjusting the center vs. stereo spread, you can do other tricks like eq' ing the mid differently from the side signal. A cool 'secret wepon' when needed.  Just make sure your matrix is adjusted to null the difference signal well if using a mixer instead of a matrix box.

Another other more arcane technical reason for possibly running M/S is that the M mic is pointing directly at the center of the souce.  Most mic and pattern responses are more acurate 'on axis' than 'off axis' and most other coincident or near coincident setups are more or less 'off axis to the center of the source.
Title: Re: Mid-Side tricks and technique
Post by: Nick's Picks on June 14, 2006, 04:09:11 PM
so whats a good software choice for doing the matrix's?
i'm running wavlab as my editor.  not crazy about the way it does things. 
Title: Re: Mid-Side tricks and technique
Post by: CQBert on June 14, 2006, 04:13:20 PM
Soundforge 8.0 for me ...

CQBert
Title: Re: Mid-Side tricks and technique
Post by: RebelRebel on June 20, 2006, 12:17:10 PM
www.stereosoundbook.com

also, please check out

Sound Engineering  and

the handbook of recording engineering , both by John Eargle for some really in depth info on this stuff...


Nick,

Thanks for the scan.  Thats really helpful.  Always wonder what happens when I put a little more side or mid into the mix.  I'm looking at the bottom of the second scan where they explain the formula.  Can you scan the reference page so I can see it (7-1) or tell me where I can buy this book.  Seems like a great resource to have around.

Thanks
Brad
Title: Re: Mid-Side tricks and technique
Post by: RebelRebel on June 20, 2006, 12:19:14 PM
Nick, samplitude is the best I have ever used. By a long shot. included POW-R dither, Object Based editing, DVDA burning..powerful stock plugins...

Must Read Books...Also, be sure to peruse the  the Audio Engineering Society's Internet Archive. (AES)...there is a fee, but it is well worth it. http://www.aes.org/e-lib/ I have learned a lot from snooping around there..
also http://www.saecollege.de/reference_material/index.html




Sound Recording Handbook (http://www.amazon.com/gp/product/0672225832/102-0455654-5222524?v=glance&n=283155)
Master Handbook of Acoustics (http://www.buy.com/retail/product.asp?sku=30689792&SearchEngine=Froogle&SearchTerm=30689792&Type=PE&Category=Book&dcaid=17379)
Behind The Glass (http://www.amazon.com/gp/product/0879306149/102-0455654-5222524?v=glance&n=283155)
Total Recording (http://www.moultonlabs.com/index.php/full/product03)
Tape Recorders (http://www.alibris.com/search/detail.cfm?S=R&bookbin=8114399528&bid=8114399528&siteID=xoZraCfY0Ik-fyZy0wSK9.vdK1d_e0zG_g)
Sound recording practice (http://www.amazon.com/gp/product/0198166087/102-0455654-5222524?v=glance&n=283155)
Professional Microphone Techniques (http://www.amazon.com/gp/product/0872886859/102-0455654-5222524?v=glance&n=283155)
Principles of Digital Audio (http://www.amazon.com/gp/product/0071348190/102-0455654-5222524?v=glance&n=283155)
The New Stereo Soundbook (http://www.stereosoundbook.com/)
The Microphone book (http://www.amazon.com/gp/product/0240804457/102-0455654-5222524?v=glance&n=283155)
On Location Recording Techniques (http://www.amazon.com/gp/product/0240803795/102-0455654-5222524?v=glance&n=283155)
Electroacoustical Reference Handbook (http://www.powells.com/biblio/61-0442013973-1)
Audio Engineering (http://www.powells.com/biblio/61-0634043552-0)
Handbook of Recording Engineering (http://www.powells.com/biblio/72-0387284702-0)
Audio Dictionary (http://www.powells.com/cgi-bin/biblio?inkey=1-0295984988-0#product_details)
Handbook of Recording Engineering (http://www.powells.com/biblio/61-1402072309-1)
From tinfoil to Stereo, a history of recording (http://www.powells.com/cgi-bin/biblio?inkey=72-0813013178-0)
Yamaha Sound Reinforcement Handbook (http://www.zzounds.com/item--HAL500964)
Mastering Audio (http://www.amazon.com/gp/product/0240805453/102-0455654-5222524?v=glance&n=283155)
The Mixing Engineer's Handbook (http://www.amazon.com/gp/product/0872887235/ref=pd_lpo_k2_dp_k2a_3_txt/102-0455654-5222524?%5Fencoding=UTF8)
Title: Re: Mid-Side tricks and technique
Post by: Nick's Picks on June 20, 2006, 04:29:05 PM
whoa...
thanks Teddy.
+T bro
Title: Re: Mid-Side tricks and technique
Post by: dnsacks on June 20, 2006, 05:55:29 PM
Question -- I just fininshed taping a few shows where I thought I was running 90 degree x/y cards but just found out that my left channel mic was set to figure 8.  Thus, I have a nice raw m/s of the right stack.  Is there any way to adjust the orientation (image center) of a raw m/s recording so that it will sound closer to the intended 90 degree x/y recording?  I understand off-axis coloration, etc., but feel that my mic (studio projects lsd2) is pretty neutral/accurate off-axis.

Thanks!
Title: Re: Mid-Side tricks and technique
Post by: RebelRebel on June 20, 2006, 06:01:11 PM
you can use a imaging tool like the waves imager, etc...there are hundreds. the S1 is my favorite for that task.
Title: Re: Mid-Side tricks and technique
Post by: dnsacks on June 20, 2006, 06:06:12 PM
Thanks!
Title: Re: Mid-Side tricks and technique
Post by: rowjimmy on June 21, 2006, 09:49:42 AM
+T's to you guys, nick, teddy, gut, for the edumacation and reading material.

By the time i get my own mics i'll either be dangerous or so full of trivia i'll forget how to plug in an xlr.