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So I thought I’d pose the question here; does anyone else use high quality head phones as a tool (one of many of course) for staging?
Stereo relies on acoustic crosstalk for time sensitive frequencies.
Quite simply a stereo system cannot prevent both ears from receiving signals from each speaker. The result is crosstalk at each ear. On a true stereo microphone setup, the microphone are in coincident, in theory your image should be 180 degrees apart, however the crosstalk reduces this to 120 degrees apart.
You will recognise this as the preferred position for your stereo speakers,IE 60 degrees, or 120 degrees apart.
Headphones can and do eliminate acoustic crosstalk, and therefore alter the image position back to 180 degrees apart. In theory this should be acceptable because your headphones are separated by 180 degrees, the result is a loss in image depth and width because stereo relies on this 120 degree shift to "pull" the image forward and out. One advantage is at intensity sensitive frequency band width, cross talk is removed, resulting in a much clearer image.
Headphones are great for tone and possibly setting intensity sensitive frequency band width. Time sensitive frequencies the image will appear to be on your nose at best, and in your head at worst.
I use Grado RS1, they are quite good for tone tuning.