Mono summing from stereo - implications for single speaker listening tests

[Matt_Holland]

YouTube often suggests some seemingly random videos and I nearly ignored this one.

The main theme of the video may be interesting to some of you in its own right, but I wanted to post it here for discussion as it relates to summed mono mixes used when evaluating single speakers as recommended by Toole/Amir and others.

The question is whether listening to a mono sum of a stereo mix affects the overall sound enough that we should take it into consideration for single speaker listening impressions.

 

[HalSF]

I’d be interested as well in hearing about the effects of summing stereo mixes to mono when listening with a single speaker. I’ve been experimenting with a single speaker playing mostly dedicated mono music, but I remember reading that there can be wonky unwanted sonic consequences when a 2-channel stereo separation/soundstage mix is summed to a single mono channel.

 

[AnalogSteph]

I'm pretty sure that checking mono compatibility tends to feature quite prominently in mixing tutorials. Expecting no losses at all may be a bit much, things just shouldn't fall apart spectacularly. You will occasionally find YT music videos posted with mono audio, and I have come across cases where this step had clearly been neglected because, I guess, whoever did the mix was quite green.

 

[Blumlein 88]

It will be dependent upon the mix as to how much it effects it. OTOH, using a mono signal for checking between speakers is not likely to be effected by this. Both speakers will have the same signal. I also don't recall if the tests like those by Toole using a mono mix of stereo or just one channel. However the research was done with many types of music. No doubt the mono compatibility did vary among various recordings. Yet the results were very consistent. So with the testing done it isn't a problem given the results.

 

[HalSF]

I found one of the useful things I’d read about the specific problems that can crop up when summing stereo to mono, such as phase cancellation and frequency masking, and how sound mixers can mitigate these effects.

Avoiding the Collapse: From Stereo to Mono (Compatibility) - sonible

Learn about the importance of mono compatibility and how to deal with possible problems when working with it.

www.sonible.com

 

[EJ3]

I’d be interested as well in hearing about the effects of summing stereo mixes to mono when listening with a single speaker. I’ve been experimenting with a single speaker playing mostly dedicated mono music, but I remember reading that there can be wonky unwanted sonic consequences when a 2-channel stereo separation/soundstage mix is summed to a single mono channel.

& what about running a stereo signal to a single DUAL voice coil sub?