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Full Stereo
Digital IO Bus
128x3 oscillators
256 voices
128 midi channels
96 kHz
Audio DSP
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Spartan 3E Development System .
Fully FPGA-powered synthesizer
A
Xilinx Spartan 3 FPGA board is used for sound
synthesis and video generation. 2 mouse ports (serial + PS/2) are
available for graphic control and synthesis control. Also 2
MIDI-controllers can be attached. The
DIY-Controller works with standard 230kBaud, which is 7 times
faster than normal MIDI (31kbps). A standard Controller from Döpfer is
attached to MIDI and studio gear. AD-Conversion is performed by a
professional device from Mindprint:
Music Box / MIDI Engine
The Music Engine produces MIDI-like information, based on pre defined
rhythm and tone patterns which are kept in a memory.
The tone notes are copied/doubled according to the ARP pattern, compressed in loudness and modified by the ADSR-module end then sent to the synth module
synchronously.
255 Tone Levels = quarter Notes covering 127 MIDI Notes are available.
The arpeggio module uses adjacent MIDI channels to produce MIDI
echo rather than audio echo. This is possible with a very high time
resolution using internal
high speed MIDI
creating short reflections similar to room reverb. For the slower
(normal) arpeggio the channels can use different parameters for the
voices.
MIDI input / workstation control with PS/2 keyboard
Synth Engine
The synthesizer engine takes the MIDI notes and produces audio signals for each midi channel from generic functions, tone banks, or
DDS-based. Wave table is planned.
The Synthesizer operates totally pipelined and with 50MHz clock speed
and processes 128 from 256 possible MIDI channels, has 3 oscillators
/ wave generators and 256 voices polyphony.
Listen to the demo
XILINXFPGASYNTHESIZER.WMA
DSP Engine
Also a DSP Engine performs audio processing, compression, limiting and
distortion
can be loaded into the FPGA system.
Graphical Spectrum Analyzer
Together with the VGA output of the
Spartan board, a FFT-like algorithm is used to perform a simple
graphical band analysis for 16 frequencies with a 3:2 ratio of
distance in between (central frequencies: 20, 30, 45, 68, 100, 150,
225, 340, 515, 770, 1150, 1730, 2600, 3900, 5850, 8750).
Sound Design and Sound Control can be supported by virtual
wave control using a minimal oscilloscope function in the Spartan
FPGA. Because of the limited resources, FFT is only available with a
second board.
Click here for the
former Version
(Spartan 2)
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