You know what a dolby SR is I hope?
In case you didn't know what it is...
A Dolby SR unite is an encode/decode hardware unit used when analog was king.
We speak about 2 inch tape here.
As you probably know, high end part of the frequency spectrum and analog tape don't like each other.
So the normal use of a Dolby was to put it while recording (preamp>dolby>tape machine). And what this do is boosting high end for compensate for the lost tape give.
Now when switching to repro (playback if you like), Dolby is on decode mod so you ear what your track sound like without the high end boost.
So the "trick" is to use a dolby SR unit in encode mod (extra high end boost), but not using it in decode. So when playback you still ear your track with the high end boost.
But to be honest, don't spend the 400$ a dolby SR unit cost on ebay for that...
It's not like this will killing your world or something.