GitHub Chris Webb

Resources for Yamaha Montage

MIDI tools

Several of my Web MIDI tools might be useful when working with Montage and MODX:

See the main page for instructions as the UI is quite minimal. Web MIDI requires Chrome/Chromium or another Blink-based browser, although Firefox/Gecko may also work with the Jazz plugin and extension.

MIDI messages

Some brief notes on undocumented system exclusive messages supported by the instrument are here:

Contributions to these would be gratefully received.

File format

Montage X7U/X7L/X7A and MODX X8U/X8L/X8A file formats are reverse-engineered and partially documented below:

My 2012 notes on Motif XF files are still available, and may be interesting for comparison purposes:

Again, corrections and additions would be gratefully received.

Obtaining a shell

The following subdirectory of has instructions and an image build tree for launching a shell using the firmware upgrade path in the instrument’s initramfs.

This makes tinkering a lot easier, and simple demo scripts are included to clean up preset part names and fix some buggy preset performances.

Montage runs an antediluvian Linux kernel and armhf userspace. Even the recent v3.51 firmware has a 3.12.10 armv7l kernel from a vendor tree tagged as “ti2013.12.01”, with a similarly aged glibc 2.19. To build binaries for Montage, it may be easier to link statically than find a museum with a sufficiently antique toolchain. This is not entirely Yamaha’s fault: many hardware manufacturers fall for SoC vendors’ terrible advice to use their ‘board support’ abandonware instead of actively-maintained mainline kernels.

Hardware notes

The main CPU is a Texas Intruments AM3352 (ARM Cortex-A8, 32-bit ARMv7-A architecture) with 256MB of DDR3 SDRAM and 4GB eMMC. The USB-to-device interface is that of the AM3352, but the USB-to-host audio/MIDI interface is driven by a separate “SSP2” DSP containing a Renesas SH-2A core.

Tone generation and effects are handled by two large “SWP70” ASICs in a master/slave configuration with their own SDRAM (48MB and 16MB respectively) and 4GB of direct-connected NAND flash for wave data. The CPU, SWP70s and SSP2 are interconnected both by the main address/data bus and also by I2S.

Embedded Linux hackers should probably think of Montage as a Beaglebone Black with 4GB eMMC, 256MB RAM, and some exotic DSP peripherals which have their own 4GB of flash storage for wave data.

I have a Montage 8 service manual (including schematics) and am happy to answer questions. These can be purchased in PDF format direct from Yamaha 24x7 in the US. However, Yamaha UK Parts are less helpful, only supplying manuals to ‘authorised service engineers’ to maintain a profitable but user-hostile monopoly.

Other information

Some additional information on electrical compatibility of controller pedals, capturing screenshots and attaching external displays is below:

The official documentation corresponding to Montage version 3.51 can be found at:

Firmware images can be found here:

Contact and discussion

Please send any questions, corrections or other contributions to Chris Webb <>.

GitHub discussions are also enabled for this repository to provide a more public forum to chat about Montage from a technical perspective.