Sum Difference Processing with Record 1.5 + Reason 5

Sum Difference or Mid-Side processing is easy to achieve in Record and Reason using Thor's Modular features to invert the polarity of audio signals. This vid demonstrates a custom mid-side matrix patch which routes the sum and difference channels out to a pair of manley compressors. The compressed sum/diff channels are routed back into Record and re-encoded to a stereo signal.

Propellerhead Reason5 + Record 1.5: http://propellerheads.se

Song written and performed by Goh Nakamura: http://gohnakamura.com

for the film Surrogate Valentine (fb page): http://www.facebook.com/pages/Surrogate-Valentine/113237472032453

Category:

Music

Tags:

• gohnakamura
• reason5
• record1.5
• propellerheadsw
• midside
• sumdifference
• mastering
• surrogatevalentine

[iseeyou275]

What exactly is the sum difference used for ? What is it credited for doing ?

[PeffTV]

@iseeyou275 Mastering engineers use the process i've described in the video to make adjustments to a mix. i've seen some cool stuff like deessing vocals or tweaking cymbals in a 2 track mix.

Some stereo microphones use this technique to control the stereo width. A vocal eliminator uses this process to eq out the vocal from the sum.

A friend turned me on to a cool trick: check the difference channel to check for compression artifacts. google: mikewellsmastering and check his blog

[phobik2000]

Is the outboard gear necessary or could just use Reason, as it already has compressors?

[PeffTV]

@phobik2000. no it's not necessary to use outboard compressors. The original patch has compressors and multiband compressor arrays configured in the combinator. The sum difference configuration also works great in Reason 4.

[phobik2000]

@PeffTV From what I've read, Record implements a 64 bit summing in the Master mixer, which gives more headroom, but I don't think that is available in other devices or Reason, so maybe affecting the mix. I could be wrong thought.

[PeffTV]

@phobik2000.  I can't be exactly sure but i think the sum diff process is running at 32bit fp. I discovered that sum channel was clipping on the way out to the converter which is why i adjusted the encoder values to 75. Originally they were at 100/-100.

[Discordanian]

@iseeyou275 If you use coincident mic-ing you can use M+S (mid + side) to control the stereo width. Very useful for live recordings.

[01adhdave]

Thank You.

[pmg888]

@PeffTV Is there a sum difference preset in record???

[Dogboy73]

For God sakes man, when is your 'Power Tools for Record' coming out? Please tell us you are working on one. This stuff is fantastic ;-)

[Macariotron]

Great tutorial (great song, too!).