Alesis D4 Version 1.04 EPROM Firmware Upgrade Update


Firmware for Alesis D4

SKU: FW-22 Category: Tags: , ,


Alesis D4 firmware OS upgrade v1.04 – Final revision

This is firmware revision 1.04 and is the latest official released operation system by Alesis. This operation system update/upgrade requires one eprom chip


  • Added – The trigger inputs now have an adjustable VCURVE parameter on the first page under EXT TRIG. (Where TYPE was.) This parameter selects one of seven pad-force to midi velocity response curves to suit different playing techniques.
  • Improved – The signal threshold for the diagnostics trigger self-test has been lowered even further to keep units from failing unnecessarily in repair.
  • Improved – The dynamic voice allocation scheme has been improved so that voice-stealing is less noticeable.
  • Improved – the system exclusive receive routine has been modified so that the time out period used to detect unplugged midi cables and unfinished system exclusive messages is now 250mS instead of 80mS as in earlier versions. This was done to allow slow computers more time while transmitting to the D4 before the D4 panics and aborts the sysex load. In addition, the LCD will now correctly display the “MIDI BUFFER OVERFLOW” message when the buffer overflows during sysex reception instead of the “SYSEX DATA ERROR” message.
  • Fixed – voice allocation routine that would cause short sounds or individual samples within sounds to drop out or sputter until the machine was powered off.
  • Fixed – A bug that could prevent the user from selecting a new trigger note number for triggers 3, 7, and 11.
  • Fixed – machine crash if a flurry of notes were sent to the D4 and if some of the voices assigned to those notes were set to SINGLE, GROUP 1, or GROUP2 mode.


  • Fully verified before shipping and professionally packaged in anti-static material.
  • To check the version on your unit, press both <CURSOR> and CURSOR> buttons at the same time and it will display the version.