M/S recording for guitar cabs

[pylet2000]

So I got my Digi 002 board back from BlackLion Audio over the weekend, and got to test out my new Cinemag equipped Apex 205 ribbons. It was a good weekend.

I tried messing around with stereo micing, never really gotten into it before (a big thanks to Harvey and everybody that contributed to "the big thread!!!" My recordings got much better after reading that). I set up a Blumlein pair on my Supro clone guitar amp to start with, and wasn't floored or anything. Not bad, but the stereo image wasn't amazing and the amp didn't sound very present. I've done better with 2 or 3 dynamics. Then I set up a M/S pair, using the modded Apex 205 and an MXL 960 (nice tube mic for cheap, IMO). I copied, inverted, then panned the ribbon tracks. Talk about cool! Presence, good body, wide stereo image, smooth top end. It almost has the sound of recording multiple guitar tracks, without all the tuning/timing slop that comes with multiple takes of the same line. Very powerful sound, and it was only a lightly driven rhythm guitar. I've spent a lot of time trying to get good driven guitar tones on disk, it's harder than it seems it should be, I'm glad to have finally gotten something lively and active sounding!

Thanks again folks, maybe I'll post some clips when I can pull myself away from the console.

 

[cusebassman]

From your description you copied and inverted tracks, and then took the originals and copies and hard panned them? Have you tested this in mono? I only ask because, from your wording, it seems like playing back in mono would cancel out those guitar parts. Just curious!

 

[pylet2000]

I did put it back to mono with matched levels, and it will completely cancel the ribbon portion of the track. Makes sense, seeing as how it's the exact same source, inverted, played at the same volume right? The LDC mic still remains when summed to mono, so the guitar part doesn't completely dissappear in a summed mono environment.

Reading about the M/S recording technique, some very clever folks will explain how a 'figure 8 pattern' placed sideways in relation to the source, combined with a forward facing mic signal (directly towards source, positioned as close as possible to the figure 8 mic), minus the inverted signal from the figure 8 mic (which does create cancellations like you'd expect), will leave a signal that when properly panned, appears to be coming from one side or the other. Due to some hard to textually explain 'differences of sums' kind of math, you get a really cool stereo micing technique that when squashed to mono still sounds okay.

The wiser and more experienced folks could explain the science far better than I could ever attempt to regurgitate.... But I can vouch for it being a really cool micing technique.