Topic: Mono/stereo mathematical relationship
I have just bought the ADI2, wonderful piece of equipment which I am very pleased with. Last night I had occasion to switch it to mono, exceptionally bad stereo mix of a mono original, and the perceived sound level dropped which prompts the question, how have RME applied this?
Years ago when I was in BBC Engineering, M=A+B-3dB, the IBA used M=A+B-6dB which the BBC has now adopted as their standard also. Apparently the original was too difficult for non BBC types to cope with. I also believe the EBU possibly used M=A+B-4.5dB. THis was all done so that the same signal heard in mono on a single loudspeaker and in (stereo) on a pair of loudspeakers would be at the same subjective level, hence the varying subtractions to achieve this.
I appreciate within the ADI2 a monoising adds A and B and sends it to both L and R outputs so I would expect the sound level to either increase or remain the same, it seems sensible to ask though what is actually happening.
Regards
Martin