Free Mono Monitoring Trick

Seasoned recording engineers often audition their mixes in mono to check for phasing problems that might occur on the mono speakers in TVs and PA systems. Collapsing a stereo signal to mono also gives you another perspective on how well sounds are blending. But because I run audio straight out of my computer into powered speakers or headphones, I've never had an easy way to monitor in mono.

That shortcoming became more annoying when I started recording telephone interviews for the Digital Media Insider podcast. I like to edit audio in BIAS Peak, so to gain access to both sides of the conversation, I usually created a stereo audio file containing my voice on the left channel and the interviewee's on the right. Those "dual-mono" files are easier to edit, but listening to them without going crazy required an absurd pile of adapters.

While working on a recent episode, I stumbled on a simple (and free) solution: I open the MDA Combo or Image plug-in and set it as follows:

These settings pan the left and right sides of a stereo file to the center. You'd need to run only one of these plug-ins at a time, of course, so I've bypassed Combo here.

The MDA plug-ins run on Mac and Windows in both AU and VST format. I also found an even simpler AU/VST plug-in called Monomaker from DestroyFX. At last, I can return the ridiculous adapter chain to the parts box!

Have you stumbled across unexpectedly helpful plug-ins too? Please leave a link.