Re: Bug? Clicks while recording audio (In) from MIDI (out)
Re: Bug? Clicks while recording audio (In) from MIDI (out)
- Subject: Re: Bug? Clicks while recording audio (In) from MIDI (out)
- From: Josh Whitver <email@hidden>
- Date: Tue, 11 Feb 2003 15:37:07 -0600
I'm replying to the list, as Kurt raised some points that I should clarify.
>
>
> This works, except for one thing. Every time there's a MIDI note
>
> event, I
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> get a strange click in the audio that's coming in.
>
>
Interesting. Have you tried using some other program to record the
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audio? It could conceivably be a bug in "Audio In".
Yup; tried another app, too ("Audio Recorder" was its name).
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>
Also, I would recommend checking that you have the most recent driver
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for your MIDI interface. I know MOTU has silently updated the driver a
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few times.
>
Yup; the newest version is 1.0.0, from November 2002, and that's what I'm
using.
>
I assume you are using the built-in audio input on your machine, right?
>
What happens if you don't plug anything into the audio input on the
>
computer? Do you still get clicks? My guess is you'll still get them,
>
but we might as well check...
Now *this* is interesting. With no input, I consistently get some very
strange interference that seems to correspond inversely to CPU activity.
Whenever the CPU is relatively idle, I get what sounds like morse code.
Whenever the CPU is doing something, I get what sounds like a tiny little
motorboat puttering around (this puttering is much quieter than the Morse
Code sound, though). There's a sample of this (in MPEG 4 audio, since
QuickTime can't export to MP3 -- how dumb is that??) at:
http://www.whitver.net/noinput.mp4
The first couple of seconds, I hit record in the Audio In app, and switched
to QMidi, and hit play on the concerto MIDI file. The middle section, the
CPU was busy playing the MIDI, but there were some idle milliseconds, so you
get the "motorboat" sound with some "Morse code" interspersed. Then I hit
stop in QMidi which freed the CPU, giving us the "Morse code" sound
exclusively. The putterings of the "motorboat" I heard do not at all
correspond to the MIDI events.
So maybe we have 2 bugs? Or poor shielding between the CPU and the audio
input? Dunno, but it's weird!
--
Josh Whitver
email@hidden / email@hidden
Mac OS X vs. Windows XP:
Typical Microsoft...Take something from another company then P on it.
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