GUS Programmer's Digest Tue, 21 Sep 93 0:07 MDT Volume 4: Issue 14 Today's Topics: perc patch madness Standard Info: - Meta-info about the GUS can be found at the end of the Digest. - Before you ask a question, please READ THE FAQ. ---------------------------------------------------------------------- Date: Mon, 20 Sep 1993 20:13:12 -0400 From: aa344@yfn.ysu.edu (Joseph Maruschek) Subject: Re: perc patch madness Message-ID: <199309210013.AA19914@yfn.ysu.edu> Well, I don't have ready access to the FTP archives at the moment, but I did take a look at several percussion patches. In every case, both the high and low frequencies were set to match the MIDI note that corresponds to the GM mapping of the percussion. For example, highq points to D#1, slap points to E1, scratch1 points to F1. Actually, these notes are an octave lower than they should be. In some cases, the root frequency is set exactly the same as the low and high frequencies, and sometimes it is different. Do the MIDI interpreters in playmidi, ultramidi and the Windows drivers use the root frequency at all? I don't think so. I think that they simply play back the sample at the specified sample rate whenever that perc patch is played. What does the root frequency mean for a percussion patch anywhay? Most percussion sounds have no definte pitch. The way that the Gravis perc patches are set up means that you cannot use a patch on a different MIDI note. F. Dion got around this limitation by making the low and high frequencies cover the whole keyboard in his TR-808 drum patches. You can put his drum patches on any MIDI note. What I think is that the root frequency is ignored. The sample is played at the sample rate indicated in the patch header when a MIDI note is played on channel 10 that matches the note number in the .cfg or ultrasnd.ini file and also falls in the range of the low and high frequencies. I don't think that any pitch shifting occurs for perc patches. If so, when and how much? -- aa344 is Joseph Maruschek 3 3 3 3 3 IBM PC SIGop, Youngstown Free-Net D D D D D motto: Strive for the simplest and the best. | | | | | : : : : : ------------------------------ End of GUS Programmer's Digest V4 #14 ************************************* To post to tomorrow's digest: To (un)subscribe or get help: To contact a human (last resort): FTP sites: archive.epas.utoronto.ca pub/pc/ultrasound wuarchive.wustl.edu systems/msdos/ultrasound Hints: - Get the FAQ from the FTP sites or the request server. - Mail to for info about other GUS related mailing lists (UNIX, OS/2, GUS-MIDI, etc.)