Alesis Midiverb IV / 4 firmware OS upgrade: v 1.04


Firmware for Alesis Midiverb IV / 4


Alesis Midiverb 4 firmware OS update v 1.04

This is firmware update 1.04 and is the latest known official released operation system by Alesis in 1997. This operation system update/upgrade requires one eprom chip as revealed in the article`s photos and the chip will be labeled to help you locate the correct chip socket. For more info, please check below.

Features/improvements from earlier firmware to 1.04:

  • Fixed a bug which was causing the MIDI Channel to be off by 1 after cycling the power.
  • Fixed a problem which caused Pitch Shifter to be inaccurate when shifting down. Also, improved the sound quality. Because of the above changes, some of the Pitch Shifter programs changed slightly.
  • Fixed problems with Compare Mode so it behaves consistently. Now it works as described in the manual.
  • Entering/exiting Compare Mode doesn’t cause the audio to crackle.
  • Improved MIDI Modulation for the LEZLIE>ROOM Configuration.
  • Added support for the Cascade pixel on the new LCD glass.
  • Added an LCD Test


  • Fully verified before shipping and professionally packaged in anti-static material.
  • The IC socket is located at U2
  • You can check current software version by pressing [PROG] and [EDIT] simultaneously