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Product Manuals


Owner’s manual Rev A


Owner’s manual Rev B


Owner’s manual Rev F / m108 Control Software Manual

m108 Control Room Out Option Field Install

m108 Dante Option Field Install

m108 DigiLink Option Field Install


Owner’s manual Rev A


Owner’s manual Rev A


Owner’s manual Rev B


Owner’s manual Rev G (with A/D module option)


Owner’s manual Rev E

Owner’s manual Rev C / Deutsch

m905 Digital Upgrade Field Install

m905 IR Option Installation revA

m905 IR Option Installation Rev A  (unit serial numbers: 905001-905294)

m905 Phono Option Installation Rev A


Owner’s Manual Rev Q

m908 SD card tech bulletin (12/2023)

m908 system specifications Rev G

m908 System Flow Diagram Rev D

m908 Workflow Templates
(.xlsx spreadsheets to show workflow structure)

m908 Dolby Atmos Target Curve Tech Bulletin

m908 Rear Speakers Bass Management Bulletin

m908 Ravenna Field Installation

m908 Phono Module Field Installation

m908 Digilink Module Field Installation

m908 Dante Module Field Installation

m908 ADC Module Field Installation

m908 2.1.x SD Card Replacement Instructions


Owner’s manual Rev C

m920 quick setup guide


Owner’s Manual Rev B

Setup Menu Quick Guide


Owner’s Manual Rev E

spacebar stereo

Owner’s manual Rev C

spacebar modular

Owner’s manual Rev E


Owner’s manual Rev C

FELiX 2 Quick Guide


(first generation)

Owner’s manual Rev E

Connection Guide

Quick Guide

Block Diagram


Owner’s manual Rev D

Connection Guide


Owner’s manual Rev C


Owner’s manual Rev B


Owner’s manual Rev B

Firmware Updates


Field upgrader, for updating from version 2.1.X and up:

m908 system firmware version 2.2.0

m908 firmware update instructions (read me!)

m908 firmware release notes 2.2.0


Migration package, for updating from version 1.0.X to version 2.1:

m908 migration upgrade

m908 firmware 1.X to 2.1.X migration instructions (read me!)


m908 system firmware version 1.0.9

m908 firmware release notes 1.0.9



m908 Ravenna Firmware version 1.6  (requires m908 system firmware v2.2.0)


m108 System Firmware v1.12

m108 System Firmware 1.12 release notes

Windows DFU application for m108 and m905


m905 system firmware version 1.18

m905 firmware release notes 

Windows DFU application for m108 and m905

m900 / m9XX

m900 / m9XX firmware v 2.4 (5/11/2018)

m9XX firmware v 2.01

m900 and m9XX firmware Instructions and Release Notes


m920 system firmware version 1.5 (09/06/2017)

m920 system firmware version 1.4 (09/02/2016)

m920 system firmware version 1.3 (12/28/2014)
m920 firmware v 1.3 disables decoding and playback of DSD over PCM ‘DoP’ received via the m920 AES3 and S/PDIF. For ‘DoP’ operation, instal firmware version 1.2

m920 system firmware version 1.2 (9/29/2104)

m920 firmware release notes


m904 firmware update (main unit v1.04 / remote unit v1.05)


m906 firmware update (main unit v1.08 / remote unit v1.07)


m802 system Firmware (m802 preamp v5.1 / RCU v6.0)

released 8/22/2016. zip file contains the firmware, the firmware upgrader programs and all the necessary documentation to properly ugrade the firmware in your m802 unit.m802 system firmware update (preamp v2.2 / remote unit v2.0)

zip file contains the firmware, the firmware upgrader programs and all the necessary documentation to properly ugrade the firmware in your m802 unit.

MAC OS X DFU appnot currently available
Discontinued Products


Owner’s Manual Rev H

m904 / m904b

Owners Manual Rev H


Owners Manual Rev A

m903 quick setup guide


Owners Manual Rev B

m920 quick setup guide


Owners Manual Rev G


Owners Manual Rev E

model 101

Owner’s manual Rev C


Owner’s manual Rev A


Owner’s manual Rev A

model 201

Owners manual Rev C

model 901

Owner’s Manual Rev A

model 801 (1995 – 2006)

Owner’s manual Rev C

m801 (2007 – 2018)

Owner’s manual Rev B

Lunatec V3

Owner’s manual Rev E

Digital output polarity issue information (unit serial# V3001-V3496)

Voltage calibration procedure

DC input pin adjustment proceedure

Lunatec V3 firmware update form

Lunatec V2

Owner’s manual 172k

Voltage calibration procedure

Voltage calibration procedure html

AC adaptor operation issues


Owner’s manual Rev I (includes RS485/RS422 Serial Port Information)

Owners Manual Dante Addendum

RS485/RS422 Serial Port Information

NOTE- Earlier versions of the model 801 and model 201 manuals depicted the positions of the XLR pins incorrectly in some of the cable termination diagrams. While the pin numbers are correct, these diagrams can be confusing. Please download the current version of the appropriate manual for your preamplifier.

model 801R

Owner’s manual Rev A(For Software version 1.3)

Owner’s manual Rev B (For software version 1.4)

Software upgrade instructions

Software upgrade instructions

RCU serial cable diagram
These dowloads are .zip files which contain the firmware, the firmware upgrader programs and all the necessary documentation to properly ugrade the firmware in your unit. Both the m904 and m906 require two seperate firmware upgrades: one for the control firmware (RCU or m904 frontpanel controls) and onefor the mainframe processor firmware. The m905 has 3 firmware upgrades – the RCU, ACU and the XMOS processor

Note: please contact your local dealer or us directly (1-303-443-7454) to request the necessary WA059 PC interface upgrade cable. There is no charge to for this item, but you must have it to upgrade your m904 or m906. The m905 has USB upgrader ports on both the main chassis (ACU) and the remote control (RCU).

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