macProVideo.com
Forums
  • Kyjocuy
    Posts: 32
    Joined: Sep 18th, 2007, 06:13
    semi-random audio glitch on playback
    On playback of a 96k mix, ready for bouncing, I am hearing some level glitches on the main vocal track, usually in the same region, often in a slightly different place, sometimes not at all. When soloed, it is there, in the sample editor it is not. I have bypassed every plugin one by one and cannot find a reason. I have increased buffer size. I cannot find the cause. CPU and disk activity minimal. Please help!!! 8-core MacPro, Logic 9 latest, 2 x UAD cards, Black Lion clock, FF800.
    Reply
  • Rounik Admin
    Posts: 8713
    Joined: Dec 16th, 2006, 08:13
    Re: semi-random audio glitch on playback
    So this in Logic 9.1.4? Are you in 64-bit mode? Have you tried in 32-bit mode (or vice versa)? Do you have the latest drivers for UAD and other plugins and hardware? Does it only affect this one project? Which 3rd party plugins do you have bypassed and not bypassed in the project? Thanks R
    Reply
  • Kyjocuy
    Posts: 32
    Joined: Sep 18th, 2007, 06:13
    Re: semi-random audio glitch on playback
    Thanks, Rounik, I have tried bypassing everything 3rd party: Manley EQ, various compressors, Pultecs etc. I have the latest drivers, also the latest LOGIC (I'm not on that computer right now so I can't say which one). I recall other projects having random blips, but they haven't shown up in bounces before. I thought I had cured it by using larger buffers during mix down. One point, though, in the region where it happens, I automate the pitch corrector on and then off for one phrase. I thought that with the large buffers, the latency might cause a blip a while after the unit came on, but even when I disable the plugin manually, it occurs. Pain in the... Steve.
    Reply
  • Rounik Admin
    Posts: 8713
    Joined: Dec 16th, 2006, 08:13
    Re: semi-random audio glitch on playback
    Hey Steve, The latest version of Logic 9.1.4 was released a couple of days back. So if you ran software update within the last 2/3 days you should have picked it up. - Try File > Save project as... and include all assets. - Try deleting the automation relating to the pitch corrector. Do the blips still happen? - If not, then place the pitch corrector on an Aux channel and send to that Aux from the original track. Then try automating the send level instead of a simple bypass. If the blips still happen then ... - If you switch the sample rate to 48k (and converting related audio files) any improvement? - Are you in 64-bit or 32-bit mode? - Do you have any tracks using flex? - Can you visually see on any of the level meters when the blips happen? - If you switch from your audio interface to using Built-in, do you still gets blips? - Also try: Remove all plugins from the Output... - and even removing all plugins (not just bypass) and see if the problem still occurs... then start adding the plugins back into the project.
    Reply
  • Kyjocuy
    Posts: 32
    Joined: Sep 18th, 2007, 06:13
    Re: semi-random audio glitch on playback
    Rounik, I added a PS to my last post but must have screwed something up, as it did not appear! I am in 64 bit mode. I will try 32. Also, I have not got the latest upgrade...I have not been online for a over a week. I'll try that and your other suggestions. I like the idea of the aux send; I'll have to automate a mute of the channel as well, but I'll do a fade rather than a mute. No meter evidence, it is not a spike, more like a bad edit (but it is not an edit, and it moves!!!!) Tried the "remove from output" trick already... I am sending a prefade signal to a parallel compressor on that channel, but even removing that (by turning off the send) doesn't work. S
    Reply
  • Kyjocuy
    Posts: 32
    Joined: Sep 18th, 2007, 06:13
    Re: semi-random audio glitch on playback
    Also, yes there is flex in other tracks, but not this one. Steve
    Reply
  • Rounik Admin
    Posts: 8713
    Joined: Dec 16th, 2006, 08:13
    Re: semi-random audio glitch on playback
    Thanks Steve. Do try 32-bit mode and the latest version of Logic. I forgot to ask what version of OSX you're running? ...Ah... I see you've updated your forum details.. and beat me to it :-) Try some of the suggestions and let me know how you get on. Best Rounik
    Reply
  • Peter Schwartz
    Posts: 545
    Joined: Sep 15th, 2007, 06:04
    Re: semi-random audio glitch on playback
    I'm going to suggest that you double-check the track and make absolutely sure that flex isn't enabled. A flexxed audio region, especially combined with any crossfade edits between regions, can cause random glitches.
    Reply
  • Kyjocuy
    Posts: 32
    Joined: Sep 18th, 2007, 06:13
    Re: semi-random audio glitch on playback
    Thanks Ski, I will try various things today (my time). This region is quite on its own, though there are crossfades elsewhere on the track. I am pretty sure there is no flexing on this track, as I usually redo vocal takes and comp, rather than manipulate (although the client wanted a pitch adjustment in this region). That being said, if flex IS on, what are the consequences of turning it off? Will any changes "unflex"? Should I bounce-in-place instead? My studio machine is kept offline, so today I will run the latest logic update as well. Steve
    Reply
  • Peter Schwartz
    Posts: 545
    Joined: Sep 15th, 2007, 06:04
    Re: semi-random audio glitch on playback
    Perhaps a bounce in place (or just a regular ol' bounce) would be a great litmus test. Solo the vocal and bounce it. Listen critically to it afterward and see what you end up with.
    Reply
You must be logged in to post a reply
Recent Threads
Recent Posts
Feedback
Course Advisor
Don't Know Where To Start?
Ask A Course Advisor
Ask Us!
Copy the link below and paste it into an email, forum, or Facebook to share this with your friends.
Make money when you share our links
Become a macProVideo.com Affiliate!
The current affiliate rate is: 50%
Classes Start Next Week!
Live 8-week Online Certification Classes for: