FYI, FM stereo and MP3 are also M/S encoded formats, the L/R signals are derived when they are decodeded by the tuner or player.
Any X/Y (coincident) stereo recording that has been stored digitally can be re-encoded as M/S without a conversion to analog. Similarly any M/S stereo recording that is stored digitally can be rematrixed to left/right stereo, with different matrix parameters if desired--again without any conversion to analog being necessary.
--best regards
This gets to something I've wondered-
If one is planning on adjusting the M/S ratio in post, one would traditionally record the M & S feeds directly without decoding in the field, then adjust the L/R output later post.
Let's assume that post work is going to be done with the original digital files in a DAW. There is no additional D>A>D conversion required to do the matrixing and all the summing is done via a plugin or DAW routings. In that case, is there in any reason to record the raw M/S signals and NOT just record the L/R matrix output with the recorder if the preamp or recorder has that capability? You could then at least listen to the resulting recording (without a decoding matrix) before preforming the DAW work even if the matrix ratio could use further adjustment. That's a plus.
The question is.. Does the additional matrixing (done by an analog circuit I assume in the preamp or recorder to produce the L/R signals and done digitally in the DAW from L/R to M/S) impact the quality of the audio?
Trying to think through potential issues other than the one above.. Do the 'on-the-fly' M/S decoders in preamps and recorders allow for independent ratio adjustment of the decoded output or is that function typically just handled by the input gain of each channel?
And.. do any of you fellows adjust your non M/S coincident recordings in post using these techniques?