I never used any noise reduction beyond DBX which is actually "dynamic expansion" or whatever marketing called it- that did not depend on the original recording conditions.
But with Dolby NR, yes, the same decoding must be used to match the encoding of when the recording was made. Basically a compression that is decompressed on playback, to "preserve" the high frequencies. I never liked recording or playback with it.
But with Dolby NR, yes, the same decoding must be used to match the encoding of when the recording was made. Basically a compression that is decompressed on playback, to "preserve" the high frequencies. I never liked recording or playback with it.