With more and more computer power available it becomes normal to have a lot of stereo tracks. In the past it was different because every instrument was mono and placed to a specific position over the stereo field and sent to a rack of stereo effect that widened the effect.
Today artists develop their own stereo fields and it’s perfectly normal to get stereo tracks of every instrument for a mixdown.
I often get hired to make analog mixdowns on my studio but my soundcard has just 8 MONO outputs. So how to preserve the original stereo fields? To do this I had to develop a technique based on multiple takes that always proved to be working great!
1) Load all STEREO tracks on the DAW and assign every one of them to a mono output so that LEFT and RIGHT are mixed in MONO. If there are more than 8 tracks it will be necessary to group some together following a general EQ rule so that tracks with similar frequencies can be outputted together.
2) Make sure the DAW panning law is set to -6dB. This way any hard-panned track will end up having the same volume as if centered.
3) Set the 8 outputs to the mixing desk and have all tracks panned to CENTER POSITION.
5) Once the MIX is ok it’s time to record. This is achieved in two takes: one for LEFT and one for RIGHT. Have all the tracks on the DAW hard-panned LEFT.
6) Make a MONO recording of LEFT channel of the analog desk.
7) Do the same hard-panning RIGHT and recording RIGHT channel. It is important to record the RIGHT channel now because we want any stereo effect applied to be kept stereo.
8) Put both recordings on a stereo track on the DAW, hard-panning one LEFT and the other RIGHT, obviously.
9) THIS IS IMPORTANT! Set the DAW stereo panning law back to 0dB or the master will sound reduced by -6db!
10) Bounce LEFT + RIGHT to a stereo file.
The results are outstanding!
This may look a long procedure but it's not. To check if everything is coming ok it's possible to record just a clip. But most important mixing to MONO has a lot of advantages as described on the links of point #4 and usually the stereo results are much better.