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Re: synchronization of input and output
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Re: synchronization of input and output


  • Subject: Re: synchronization of input and output
  • From: Jeff Moore <email@hidden>
  • Date: Mon, 2 Nov 2009 11:35:19 -0800

I still have no idea what you are measuring against such that would allow you know that things are 10 samples late. Logic attempts to do some compensation for latency, so it essentially masks away from you what is really going on at the hardware level. What you regard as "late" is the result of Logic's compensation.

So, you'd really need to test this outside of Logic where you can see precisely what is going on at the hardware level before we can go any further here.

On Oct 30, 2009, at 5:25 PM, Taylor Holliday wrote:

It's hard to say. There isn't enough context here. You say everything is "10
samples or so late", but late as compared to what?. And, is it 10 samples
all the time? If not, what precisely is the variance?


You need to define better what you are measuring and how you are doing it
before I can provide more information.



I'll try. In order to determine whether newly recorded audio is properly synchronized with previously recorded audio, I hooked the output of my duet into its input. Then recorded audio to a separate track. The newly recorded audio is 10 samples late relative to the audio being played back. The 10 samples seems to be a constant.

Here's a screenshot showing the waveforms:
http://wtholliday.org/recording_delay.jpg

Let me know what other info you need.


--

Jeff Moore
Core Audio
Apple



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