advanced audio recording
Spartan 6 based drum computer
  128 oscillators

32 voices

128 midi channels

96 kHz
Audio DSP

Demo 1

Demo 2

A complete drum and rhythm machine in VHDL

This page shows version 2 of my FPGA-based drum computer. For technical details regarding VHDL and base board see page 1 of the article
Spartan 6 drum computer 2012.

base board of FPGA Drum Computer


64 virtual voices using 2 in parallel for 32 channels
768 kHz sound generation
enhanced 92 kHz Audio DSP processing
Echo, Reverb, Vibrato and Tremolo
Enhanced Virtual Console RS 232 @ 460 kbaud
Direct XSVGA output of settings and parameters
with real time spectrum analyzer
oscilloscope like output during wave design
enhanced midi memory
enhanced song memory
enhanced beat morph system

Spartan 6 LX FPGA System
base board of FPGA Drum Computer

A Spartan 6 FPGA board from Trenz Electronic Germany is used for sound synthesis and video generation. 2 PS/2 ports (mouse + keyboard) are available for graphic and synthesis control. Also a MIDI-controller can be attached: The DIY-MIDI-Controller works with standard 4x230kBaud, which is about 25 times faster than normal MIDI. See the MIDI 2000 page for details about my MIDI standard.

MIDI Controller

MIDI Controller for drum computer

 Drum Computer Front

To control the FPGA directly certain functions can be accessed by internal rotary encoders. Here no LED feedback is used but the values are represented on a SVGA output. There is a drum computer GUI as well as a GUI which shows directly knob positions. Therefor the screen of the front plate is used.

drum computer front skin - PC GUI
Drum Computer PC GUI

drum computer front skin - Version 2
Drum Computer Knob Representation, now with smaller keyboard but more knobs than in version 1. It has a 16 step sequencer for each channel and individual tone control for tuning the sounds in real time. As an example bass drums and toms can be configured with the right frequency to met the melody's tuning perfectly. Song and pattern programming is performed via GUI or PC upload.

Construction Details

drum computer data flow
Data Flow and interconnections of the drum computer

drum computer front skin - Version 2
3D-View of the mechanical design of the drum computer


 Current realization of the drum computer using Mentor knobs for the encoders:

drum computer front skin

Listen to a demo drum song of the DRUMMIX 2: Mix1

Listen to a demo track with simple drum sounds
together with the Pyratone FPGA Synth Engine : Mix2

The Drum Computer shows also internal settings and values like wave synthesis and levels via a virtual MIDI knob matrix:

drum computer direct vga output
Programming Screen of Drummix 2

beat morph module 2

The Drummix in version 2 again uses the formerly invented beatmorph method to resample and retime stored samples and morph in between them thus making it possible to modify the complete sound seamlessly in real time.

Read about the real time resampler

Listen to the following to morph demos:

Drum Morph Demo1

Drum Morph Demo2

Dynamic Relooped Mix

See the first version of the drum computer in VHDL here:
Spartan 6 Drum Computer with virtual console



© Dipl.-Ing. Jürgen Schuhmacher 2014