
There are currently twenty something different
emulations, each does sound different although the
author maintains that the quality and accuracy of
each emulation is subjective. One of the main
reasons for putting together this site (host by
Sourceforge which provides the rest of the services
required by bristol) is to depict all the different
emulations.
This site contains a write-up of each of the
emualated synthesisers. The algrithms employed were
'gleaned' from a variety of sources including the
original owners manuals, so they may be a better
source of information. Some of them were built just
from descriptions of their operation, or from
understanding how synths work - most of them were
based on the Mini Moog anyway. Many of the synths
share components: the filter covers most of them,
the Prophets and Oberheims share a common oscillator
and the same LFO is used in many of them. Having
said that each one differs considerably in the
resulting sound that is generated, more so than
initially expected. Each release refines each of the
components and the result is that all emulations
benefit from the improvements.
All the emulations have distinctive sounds, not
least due to that the original instruments used
different modulations and mod routing. The filter,
which is a large defining factor in the tonal
qualities of any synth, is common to all the
emulations. The filter implements 3 different
algorithms and these do separate each of the synths:
the Explorer layering two low pass filters on top of
each other: the OB-Xa using different types
depending on 'Pole' selection. The 3rd filter
algorithm is a butterworth used by for the Leslie
rotary speaker crossover.
The write-up includes the parameter operations,
modulations, a description of the original
instrument and a brief list of the kind of sounds
you can expect by describing a few of the well known
users of the synth.
Visit:
Bristol