User manual

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chaotic mess. At times, I have had this arrangement with the controls finely tweaked so
that on some cycles through a pattern, the filter resonates with the spiky, “nutty”
sounding intense Filter FM at about the frequency of the Oscillator, but at other times at
half the rate (an octave below), or less. This is somewhat like not quite blowing a
trombone into its second octave. Thus, a totally repetitive sequence can result in
randomly very different sounds. I have had settings where the state of this self-oscillation
for a particular note in the bar varies from bar to bar, but remains stuck in one state or the
other for the duration of each note.
Muffler and Audio Filter FM
The muffler works on the output of the VCA, and it is the output of the VCA which
drives the Filter FM pot. Since the Muffler decreases the level – and particularly the
extremes of level – it will reduce the effect of Filter FM and change its nature. Likewise,
the Filter FM pot will have less effect if the VCA output level is low due to the Overdrive
pot being set low.
Battery arrangements for memory data retention
Please see the separate manual concerning this: DF-Memory-Backup.pdf.
Operation from C-cell batteries
Please be wary of inadequate supply voltage from batteries or the external power adaptor
if you experience faulty behaviour with the Devil Fish’s sequencer. There can be all sorts
of trouble, such as the sequencer stopping (and not responding to front panel buttons) or
playing patterns incorrectly or not at all. There have been many instances of Devil Fish
users being perplexed at a malfunction, only to find the problems are resolved with a
fresh set of batteries.
Please use Alkaline C-cell batteries, rather than ordinary dry-cells. NiCad or Nickel
Metal Hydride rechargeable batteries are 1.2 volts per cell, and will not provide sufficient
voltage to run a TB-303 or Devil Fish reliably.
The TB-303 is fussy about the voltage of its C-cell batteries. Likewise, if it gets too little
voltage from an external power supply, then the internally regulated version of that
supply voltage will drop below 6.0 volts, and trouble may occur. The Devil Fish draws
more current and therefore is still fussier about these low voltages, however in August
2005 I began making additional changes to the Devil Fish (Version 3.0C and 4.0C as
described below in the Version History) which improve the way the CPU voltage is
generated and so make these machines somewhat less sensitive to low battery (or
adaptor) voltages than a standard TB-303. This discussion concerns the TB-303’s
original CPU. The CPU I use for the MIDI In and MIDI In and Out systems have a
separate power supply, and should not be affected by marginal drops in battery or
external supply voltage.
Devil Fishes before August 2005 generally could only work from the “top 25% or so” of
the energy available from alkaline C-cells. I estimate that a fresh set of C-cells would run