Path: utzoo!news-server.csri.toronto.edu!cs.utexas.edu!usc!apple!netcom!mcmahan
From: mcmahan@netcom.COM (Dave Mc Mahan)
Newsgroups: comp.dsp
Subject: Re: Digital Output and VU meters
Keywords: digital, DA, VU, video
Message-ID: <27517@netcom.COM>
Date: 9 Mar 91 07:29:20 GMT
References: <50010@apple.Apple.COM>
Organization: Dave McMahan @ NetCom Services
Lines: 27


 In a previous article, malcolm@Apple.COM (Malcolm Slaney) writes:
>I have a bunch of digital sounds (both 8 and 16 bit) and I often copy
>them onto video tape.  I was recently copying a tape and it was preceeded
>by color bars with a 0dB tone.  That made it real easy to set the input 
>level on the other deck....just match the 0dB.
>
>So, now I want to do the equivalent thing with the digital audio that I'm
>dubbing onto video tape.  The question is....what digital levels would
>best correspond to 0dB?  Should I put in a full-scale sine wave at some
>frequency and assume that my real signals will be ok?

It all depends on the gain of your amplifiers and stuff.  The easiest way
to do that with the equipment you have is to just record a digital tone
with a known amplitude and then play it back to see what kind of power shows
up on the VU meter.  Then, adjust your amplitude to get 0 dB.  You just have
to make sure any level adjustments are always the same when you repeat the
technique in the future.

>								Malcolm

   -dave


-- 
Dave McMahan                            mcmahan@netcom.com
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