Mono Audio Files vs. Poly Files

[Jim Rillie]

Hi group,

I have been delivering mono files to post since I got into Multitrack non-linear recording on set, with no issues from post from day 1 of this system.

I noticed recently on other subjects that people are still delivering poly files. What is the benefit of poly files?

I Think Avid Media Composer in earlier incarnations used to need them and the DV 40 for dailies, but what is the current usefulness of this format?

Time Code and unique file names should make everything more malleable for post audio, I would think. Or am I missing something?

I have the option of delivery either way, but am just asking what is the benefit one way or the other?

OT Rant:

Oh, technically, it was all so simple and standards were real when we used Nagras and Stellavoxs, and Mag film etc

Regards,

Jim Rillie

[Toy Robot]

This thread should help you: There's a section regarding Mono vs. Poly and a link to another thread with the subject covered.

Hope it helps Jim.

[stevegrider]

For what its worth, I am always asked to deliver poly files. No one has ever requested mono files from me.

[Tom Visser]

Poly here, although I can do either.

[Jeff Wexler]

As stated before, I have never been asked to deliver mono files. I have always delivered poly files from the very beginning. The relative advantages or disadvantages of mono vs. poly have been discussed (thanks for posting the various links above) but the main focus is the same: ask the question to those in post who will be the recipients of your work. In the rare instance (rare in today's world) that they are not able to deal with poly files, give them mono files if that's what they want. There is no downside to poly files as far as I know.

The other issue, of course, relates to the particular recorder you are using. If there is a professional recorder you wish to use that cannot do poly files and post wants poly files, then you have a problem. Again, ask the question (can they deal with mono files).

[Philip Perkins]

The only issue I've run into with poly files (besides inexperienced editors) is with polys with more than 12 tracks (which can't be busted in Wave Agent). I've busted 24 track polys in BWF Widget, but in general really wide multitrack recordings are done as mono files--as far as I can tell only us video audio types use polys for other than stereo pairs. In recent years I've turned in many many days of 4 track polys w/o problems w/ anyone. As I see it, the main reason to use polys is that the whole stack can be imported, stored and synced as one object instead of several.

phil p

[Peter Mega]

I haven't delivered a poly file in about 3 years now. All the shows I work on request mono.

One discussion I had with post some time ago was that they split poly into mono files anyway so when I offered to deliver mono, they said great, one less step for them.

But as Jeff says, ask post what they want.

Cheers

Mega

[Harris K]

I was delivering poly files to a regular client for about a year until the staff assistant editor, who I checked in with regularly, mentioned an issue.

Apparently, their instance of final cut (didnt catch version number but its not X) is stupid with polys and was only ingesting the first two tracks ( L+R mix from 788) and igniting my isos. They'd been splitting everything to monos with wave agent for a year, adding unnecessary time to their already tight turn-arounds. Switching to mono deliverables cured everything.

So, there's a potential issue with polys. Haven't heard of this before or since, though.

[soundslikejustin]

I'm pretty sure that's a user preference setting...I've been delivering 4 track polys to FCP 7, AVID and Premiere clients for a while, no problems.

Apart from that uneven track count thing AVID had for a while...

[Chris Campion]

The only reason I started (and continued) to deliver Mono files was because years ago I remember pro tools having a problem importing 3 channel polys. I'm sure its sorted now but Its just habit now.

[John Steigerwald]

In the reality market, I tend to use mono files only for the fact that 9 times out of 10 the mix to camera gets used and they're only going to the multitrack for a specific cast members audio.

With mono they can just look up the date, time and name and pull in only what they need.

[Marc Wielage]

The only reason I started (and continued) to deliver Mono files was because years ago I remember pro tools having a problem importing 3 channel polys. I'm sure its sorted now but Its just habit now.

The Avid problem was some kind of odd/even thing -- as long as you had an even number of tracks, it worked. I'm so superstitious, I'll record a blank channel "just in case," to give them an even number of channels.

To me, all mono tracks is cumbersome and you wind up with a zillion different files that are hard to organize. All current versions of editing and mixing software can deal with Poly files with no problem. But... note that Pro Tools just converts them to mono on ingest. To me, it's a convenience for the sound mixer, and not a lot of trouble for the post department to deal with. It does help when the iso track is named with the character's name.

[Jeff Wexler]

The Avid problem was some kind of odd/even thing -- as long as you had an even number of tracks, it worked. I'm so superstitious, I'll record a blank channel "just in case," to give them an even number of channels.

I had the Avid problem a long, long time ago, may have even been the first time it was discovered (there were not a lot of mixers doing file based recording back then). The Avid in use was very old, even at that time, still running Mac OS 9 (the Studio owned a whole bunch of them and refused to update ANYTHING --- not surprising considering that Avid used to charge for a software update what we know pay for a whole computer). I had to record BLANK tracks as well to accommodate this job but I really didn't like doing it. The whole odd track count thing went away soon after that I think.

[Michiel]

At the film school I have been teached (two years ago) to always deliver mono files. The reason being that some editing software reads skipped tracks as actual audio, resulting in mute tracks. For example: If you record tracks 1,2 and 4, track 3 would appear as mute audio in the editing software.

@Marc Wielage: Pro Tools 10 can work with poly files as well, without having to split them into mono files.

[Marc Wielage]

Hey, that's good news about Pro Tools 10! I knew they had greatly improved its ability to read track names and also the very annoying "no timecode over Hour 12" problem.