Program (Patch) Change Commands - Roland TR-808 Owner's Manual

TR808-M
For all others "Velocity" values (from 2 to 126), output level of sound generator is linearly
interpolated between "Dynamics From" and "Dynamics To" values.
So maximal possible dynamic range is set for value 0 for "Dynamics From" and value 127 for
"Dynamics To". This range corresponds to range of ACCENT controller on TR-808's panel if sound
generators are driven by TR-808's internal sequencer.
Remark 1:
generators reaction to the MIDI
Velocity is different
particular drum sound. Some of the
sounds have large accent sensitivity
range and some of the generators
provide only minor changes with the
higher accent level. This is done by
the TR-808 construction and it is
not possible to change it without
major TR-808 circuitry modification.
Remark 2: Dynamic range is
defined for every
independently so if one sound
generator is assigned to more than
one MIDI note, it may have different
range for every of that notes.

4.1.2. PROGRAM (PATCH) CHANGE COMMANDS

Program (Patch) Change commands choose method of control and time synchronization for
internal sequencer and method of launching of sound generators of TR-808.
The interface uses full range of program numbers 0 to 127. Required control functions can be
programmed (with help of SysEx Message) for any program number independently. Also a program
number can be ignored – no changes occur after that program number receiving.
User can choose which of programs will be active after the interface reset (after TR-808 is turned
on). Global parameter "Default Program" specifies that program number.
Appropriate combination of control functions (for internal sequencer and sound generators
control) is activated in dependence on selected program number. Definition of control functions for
particular programs is listed in table 3.
• Control of tempo of internal sequencer
Tempo of internal sequencer of TR-808 can be control by TR-808's internal clock pulses
generator or it can be derived from MIDI Clock commands. Also both clock sources can be turned off.
Internal sequencer of TR-808 is totally deactivated in that case.
• Control of run of internal sequencer
Run of internal sequencer (its START and STOP) can be control by START / STOP button on
TR-808's panel or it can be control by MIDI Transport commands (Start, Stop, Continue). Also both
methods of control can be chosen simultaneously. If both sources of clock pulses for the sequencer
are turned off (see above), the sequencer is deactivated at all and it can't be launched anyway.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
TR-808 tone
for each
MIDI note
Copyright © 2015 CHD Elektroservis. All rights reserved.
MIDI Interface for Roland TR-808
Pic. 5 – Setting of sound generator's dynamics
8
Model 8-448 ver. 3.30