CB808
Introduction.
The CB808 is Roland's TR-808 cowbell sound generator adapted for modular
synthesizer use. The front panel contains all of the controls found on the original TR-808
drum machine, allowing you full control over the sound’s volume levels to mix with other
drums, and accent levels. In addition to that, the CB808 includes a pitch-modulating LFO
with control over the LFO rate and modulation depth.
About the Making of the CB808.
The CB808 is a one-to-one clone of the original circuit found in Roland's TR-808 drum
machine. During the design phase, we created additional features only when
implementation would not compromise the original signature sound, add excessive
costs, or sacrifice panel space. Cloning a circuit that was designed and produced in the
early 80's was not an easy task. A variety of obstacles including availability of the original
parts, the modern SMT manufacturing process, the dierences in +/-12V Eurorack power
versus the +/-15V of the original 808, and far many more were addressed in the creation
of this module. To learn more about the process of remaking the sound generator in this
series please refer to the BD808 user guide.
Let’s get started.
To start using the CB808, just plug a gate signal into the GATE IN and plug the CB OUT
to your sound system and set the LEVEL half way.
Dynamics and Gain.
Level Explained:
The CB808 oers an enhanced output gain stage over the original 808 design. This
addition allows the output signals to get very hot so that anything flowing from the
module will be overdriven, generating additional harmonics through distortion and
clipping of the sound. This capability is one of the most useful ways to get more sounds
out of this circuit. This eect is easily noticeable by sending the audio output with both
LEVEL and ACCENT set to max into line level instruments such as computer audio
interfaces, outboard multi-eects, mixers, and even low level devices like guitar pedals,
mic preamps etc. This enhanced gain stage will also make any synthesizer module
operate at peak levels while adding interesting harmonics or digital artifacts in the case
of digital processing modules. On the other hand, if all you want is a nice, clean 808
sound, setting the range of the LEVEL knob somewhere between 0 to 70% will cover that.
