Interesting Capitol Mastering glitch

[tormenter]

I had a SUPER weird glitch that I finally figured out after a couple hours of hair-tearing (one hour in front of a client, yikes!). There was on song on this album I'm tracking and mixing that was cutting out at the downbeat of chorus 3. All audio output ceased whether on playback, online, or offline bounce. Playback would not resume until I either turned off ALL plugins on all tracks (lots of time spent loading one plug at a time and hitting play at that spot) or if reloaded the session, it would play perfectly up to the downbeat of chorus 3 and cut off again. I bounced stems from all the aux channels, loaded them up in a new session, put a few plugins on aux sends for reverb, delay, master bus, etc., and it happened exactly the same way.

Turns out there was a non-audible waveform glitch in the backing vocal track that was aligning perfectly with something in the music and creating a spike that pushed the mastering compressor into a safety audio shutoff, like an amplifier overload circuit, but software.

After loading the stems in Logic and testing with the same master bus plugin chain (Oxford Inflator, Capitol Mastering Compressor, DMG Limitless) I figured out that the waveform glitch knocks the Capitol Mastering Compressor into a fault state and it won't reset and allow audio to pass until you turn that plugin off and back on. All other plugins in the chain are able to recover from the fault in real time.

 

[wglotz]

Can you better define, "non-audible waveform glitch"? And did you test this in a Logic project that has only the Capitol Mastering Compressor?

 

[tormenter]

Can you better define, "non-audible waveform glitch"? And did you test this in a Logic project that has only the Capitol Mastering Compressor?

There was a visible hard cut in the waveform on a vocal tail that was baked into a backing vocal stem. It was so quiet as to be inaudible even when soloed. When I solo that stem and compress it very hard I can hear a slight "pop". When I put the Capitol Mastering Compressor on the master bus of any DAW (tried in ProTools, Logic and Reaper) the clip lights stay on and the meters stick to the left in gain reduction meter mode. They don't reset until I remove and replace the plugin, then they do it again when it passes that spot in the track.

 

[wglotz]

There was a visible hard cut in the waveform on a vocal tail that was baked into a backing vocal stem. It was so quiet as to be inaudible even when soloed. When I solo that stem and compress it very hard I can hear a slight "pop". When I put the Capitol Mastering Compressor on the master bus of any DAW (tried in ProTools, Logic and Reaper) the clip lights stay on and the meters stick to the left in gain reduction meter mode. They don't reset until I remove and replace the plugin, then they do it again when it passes that spot in the track.

If you can upload that section of the backing vocal I will test for the same glitch using Logic on my system. I don't own the Capitol Mastering Compressor but I will demo it to do the test.

 

[UniversalAudio]

If you can upload that section of the backing vocal I will test for the same glitch using Logic on my system. I don't own the Capitol Mastering Compressor but I will demo it to do the test.

yeah would be interested in getting that file as well.

 

[Bear-Faced Cow]

I’m wondering how this glitch may have occurred. I have never heard of this in the decades that I have been using Logic.

jord