There are different figures out there but it’s generally said that 16mm optical track plays back “flat” between 80-100Hz and 5-7KHz, with a dynamic (signal to noise) range of 30-40dB. So use any digital equalizer to reduce output below 100Hz and above 5KHz then compression to have all the audio (loud to quiet) within a range of just below 0bB to about -30dB. Reaper has these tools included, and is a low price.
My main resources for specifications, from these two pages: Mixing for 16mm Optical Sound – filmlabs.org <https://www.filmlabs.org/technical-section/sound/mixing/> Simon Fraser doc: 16mm Film & Audio <https://www.sfu.ca/~gotfrit/ZAP_Sept.3_99/f/fsnd_lect_16mm_mix.html> Thanks to friend David Power for these notes (he has helpful audio and Resolve tutorials on YouTube): Hard limiter on master buss just shy of 0dB around -0.1dB or -0.3dB Hard gate at -30dB, so as you work you’ll hear dropouts of audio below -30 Compressor with several render-listen-repeat passes of 3 - 6dB of reduction in each pass to bring peaks down ~18dB. At this point, with ~18dB of headroom, boost the entire master buss by 18dB. The hard limiter will keep it from clipping. Play it back and listen critically — with headphones, on studio monitors, at soft, medium, and loud volumes. If there are still dropouts in the audio (i.e. the gate closing over things we need the audience to hear), repeat the steps above: 1. Compress gently “a few” times. 2. Raise the overall gain by the amount of gain reduction. 3. Playback and listen for dropouts. NB: you’ll get far better mileage out of layering compressors (reducing gain by “a few” dB in each pass) than by knocking the peaks down super hard with a single compressor. In the early compression phases, you might want to start with a fast attack, medium release to knock down any super fast transient in the material. Once things the peaks are under control, then add slower compression passes to smooth out the entire track more subtly. NB2: Because you’ll likely boost overall gain several times using this technique, you’re bound to raise the noise floor. Once at / near the end, if there’s noticeable noise, you can either try a gentle Rx noise reduction pass or two. Or, use a soft-gate to knock down noise during quieter passages. Sandy On Mon, Feb 24, 2025 at 5:03 PM Derek Jenkins <[email protected]> wrote: > Talking to the technician is always good advice, but the ones I use have > limited abilities to test the track for results in the right context. I've > had multiple tracks made, and I've found that tracks which sound > satisfactory on a portable projector may sound less so in a professional > exhibition space. I'm aiming to improve my results, so Sandy's resources > are very helpful. Thanks all! > > D > > On Mon, Feb 24, 2025 at 3:52 PM Scott Dorsey <[email protected]> wrote: > >> Talk to the man doing your optical track! Just be aware that the >> bandwdith >> will be limited and so will the dynamic range... but you don't need to >> bandlimit or crush it because he'll do that for you. You may find a >> little >> presence boost helps overcome the distortion on cheap classroom projectors >> but then again you may choose not to do that. >> >> Just make sure the timing is right and the 2-pop is in the right place, >> and give some leadin before the 2-pop. >> --scott >> >> >> -- >> Frameworks mailing list >> [email protected] >> https://mail.film-gallery.org/mailman/listinfo/frameworks_film-gallery.org >> > -- > Frameworks mailing list > [email protected] > https://mail.film-gallery.org/mailman/listinfo/frameworks_film-gallery.org >
-- Frameworks mailing list [email protected] https://mail.film-gallery.org/mailman/listinfo/frameworks_film-gallery.org
