Specifications

converter 1.5

2000 - 2005 urr Sound Technologies Inc.
76
lfo generators
In addition to the previously described input sources, converter provides 8 lfo (low frequency oscillator)
generators. Each lfo can be assigned to generate its own independent stream of midi continuous
controller data, used as a modulation source for the midi input processor, or both. All 8 lfo generators
are automatically synchronized to either incoming midi clock, converter’s internal clock generator, or
simply the tap-tempo time periods (if clock generation is undesired). Each lfo can be assigned its own
individual note length and optional target midi message type to generate (as a continuous controller
stream); additionally each lfo has its own arithmetic operator which can perform various operations to
transform the output of the lfo. This all comes together to provide a very powerful and useful tool for
using older hardware in a midi sequencing (or even live) environment.
Each lfo generator is hard-wired to a particular shape (sine wave, triangle, sawtooth, square, sample &
hold, 9-step, 5-step, asymmetrical sine) but these shapes can easily be modified by using their
arithmetic operators (for example, to turn the sine lfo into another square wave lfo, or the triangle lfo into
another stepped lfo).
The transmission of midi message streams from the lfos are controlled individually from within the
“transmit enable/disable” menu ( [F4] – [F7] – [F5] ). In this way, one or two lfo generators could be
assigned to generate midi continuous controller message streams, while other lfos are only used as
modulation sources within converter. The lfo generators as a whole source can be turned on or off
within the root realtime menu ( [Alt]-[E] ), however under normal circumstances it is suggested they be
left on as they do not require any significant cpu load.
Programming the lfo generators is very simple, and is done in much the same way as the mouse and
gameport input sources; hence all three sources are grouped into the same menu section ( [F4] ) .
Here’s how to program the sinewave lfo to generate a stream of channel volume messages on midi
channel 1:
•
Press [F4] for the game/mouse/lfo parameters menu, then [F7] for lfo settings.
•
Press [F6] for the lfo midi conversion settings menu, followed by [F5] for the sinewave/triangle lfo
settings page.
•
For the
sine LFO byte pos.
parameter type 2 to place the converted byte value from the lfo
generator in the 2
nd
databyte position of the midi messages; for the
sine LFO statusbyte
parameter type 176 (for a controller message on channel 1, or scroll using the page up/page down
keys until the parameter displays
cntrl [ch. 1]
); followed by 7 for the
sine 1
st
databyte val
parameter (indicating channel volume as the controller message type) and perhaps for clarity’s sake
place a 0 in the
sine 2
nd
databyte val
parameter (which is going to be filled in by the byte taken
from the sine wave lfo generator).
•
Next, move the cursor to the
sine tempo subdiv.
parameter and set the parameter to ¼ note.
•
Finally, enable transmission of the lfo by pressing [F4], [F7], then [F5], and turn on the transmission
of the sine LFO to begin sending a stream of midi messages.
And that’s it – the sine lfo is generating (clock-sync-able) continuous controller messages on midi
channel 1. If it doesn’t appear to be working, check the root realtime settings menu to ensure that the
lfo generators are activated (if you see the lfo lights pulsing, they are already enabled).