Stereo Phase compensation

[Lance]

I've just run into a curious problem:

I started out a session in Sonar using their drum sampler/midi sequencer for drums, then dumped all the stereo drums down to stereo pairs and imported those into SSL. That's the background...

Now I've noticed that the individual stereo drums, i.e. kick, snare, toms, et.al. are off by a few samples left to right...i.e. the kick level should be relatively even left to right, but they're not. I fixed this once before and know that I'm getting some phase cancellation which is affecting the meter output. I have done the whole... copy to two tracks, make mono, pan L-R, use JMS's latency compensator to adjust the number of sample points of the one side, then rebuild the stereo pair, then test mono..thing, so I know that this is the problem. Seems to be how Sonar2 implemented its export function. (bad design)

Short of a lot of work, I was thinking that a stereo version of JMS's latency compensator would be very helpful here. Something that allowed me to offset the left and right sides of a stereo pair independently as a plug-in.

Does anyone know if such a plug-in exists? I could really use it right now! :(

Thanks.

Lance

[Bob L]

You may want to do this adjustment on the fly without plugins or complicated mix rebuilds...

Place the same stereo file on two adjacent tracks and then jump to the top of the E mixer to the I/A section.

Left-Click next to the Mono button to popup the mono options... set the first track to L-Only and the next track to R-Only... you are now free to pan live any way you like... full left/right or even almost mono between the two tracks...

To adjust phase by samples, simply zoom way in on a kick drum transient and grab one of the tracks and slide it to line it up by transient with the other track visually... you can zoom all the way in to one pixel per sample and then also learn to use the Select Mode Nudge functions with the arrow keys to slip one of the tracks sample by sample till you like the resulting sound...

Or you can get more technical with this concept... now that the tracks are split to two tracks, pan them in the center on top of each other... push the phase rvs button on one of the tracks temporarily... as you get the slip position perfect you should hear the audio considerably dissapear or seriously phase out to almost no signal.... then you know your alignment is good... pop out the phsa rvs button... If you do this with the same audio signal on both tracks you will actually get zero audio output when you use the phase rvs.

You can leave this in the edl and do not have to rebuild a stereo mix file just to fix these drum tracks.

Bob L

[Lance]

Bob;

Thanks for the reply. Yes, I agree, this will work, up to the point that I want to make any channel adjustments, i.e. eq, comp, etc. Then I have to be back in stereo.

I did particularly like the idea about the phase reversal for accuracy.

BTW, I found out that Sonar's export function is 5 samples off. If I could have slid the right side in 10 tracks, it would have saved me 4 hours on Sunday. I didn't discover the problem until after I was almost done with my mix.

Lance

[Bob L]

Why is there a problem making channel adjustments... simply select both channels at the top of any mixer view to blacken the channel number and every adjustment you make to one will make the same adjustment to the other...

In fact use the temporary grouping functions to adjust dozens of channels at the same time if you want... this comes in handy when you have multiple tracks of background vocals or horns and you want to setup the same starting eq and or compressor settings on each of them... select them and set up one channel, and you have just done them all.

Make sure to immediately clear the selections after you are done by Right-Clicking in any of the mixer channel numbers at the top.

Bob L

[Lance]

:D Bob;

Unreal!

Been with you for years and there's always so much more to learn. ;)

Thanks. This will help greatly.

Lance