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horseshoecrabs
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Reged: 11/09/04
Posts: 13
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Re: 74LS629
10/20/10 03:04 PM


> > Can you elaborate for a non-engineer how the simulation / emulation of the sound is
> > changing?
>
> The old code was based on the data sheet, which are notoriously incorrect. The new
> code is based on testing the real IC. The old code generated frequencies that were
> too low. Lets say the real chip puts out 56kHz under certain conditions. The old code
> would only generate 30kHz. The new code generates 56kHz.
>
> Or as Kitsune Sniper said: "Funny numbers make funny sounds."
>
> D.

Thank you for the explanation!

I take it this caused higher-frequency sounds to get changed [or compressed?] down to lower tones. It definitely didn't sound right before, now it sounds perfect.







Entire thread
Subject Posted by Posted on
* 74LS629 Derrick Renaud 10/19/10 04:22 AM
. * How many games use the 74LS629? mike20599  11/07/10 02:37 AM
. * Re: How many games use the 74LS629? Derrick Renaud  11/07/10 06:29 PM
. * Re: 74LS629 StilettoAdministrator  11/05/10 10:15 PM
. * Phenomenal and incredible... Trebor  10/20/10 10:58 PM
. * Re: 74LS629 Foxhack  10/19/10 07:01 PM
. * Re: 74LS629 tamalmalamarrado  10/19/10 06:20 PM
. * Re: 74LS629 Derrick Renaud  10/19/10 07:45 PM
. * Re: 74LS629 tamalmalamarrado  10/20/10 12:16 AM
. * Re: 74LS629 Naoki  10/19/10 10:44 AM
. * Love it Sune  10/19/10 05:23 AM
. * Re: Love it redk9258  10/19/10 05:26 AM
. * Beautiful work! horseshoecrabs  10/19/10 07:04 AM
. * Re: 74LS629 gregf  10/19/10 05:12 AM
. * Re: 74LS629 Derrick Renaud  10/19/10 02:23 PM
. * Re: 74LS629 gregf  10/20/10 10:32 PM
. * Re: 74LS629 Derrick Renaud  10/21/10 02:16 PM
. * Re: 74LS629 Antny  10/19/10 08:38 PM
. * Re: 74LS629 Derrick Renaud  10/19/10 10:01 PM
. * Re: 74LS629 horseshoecrabs  10/20/10 12:02 AM
. * Re: 74LS629 Derrick Renaud  10/20/10 04:06 AM
. * Re: 74LS629 horseshoecrabs  10/20/10 03:04 PM
. * Re: 74LS629 "The Manuel"  10/19/10 03:15 PM
. * Re: 74LS629 Derrick Renaud  10/19/10 05:03 PM
. * Re: 74LS629 "The Manuel"  10/19/10 05:31 PM
. * Re: 74LS629 CrapBoardSoftware  10/19/10 09:38 PM
. * Re: 74LS629 "The Manuel"  10/19/10 09:58 PM

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