Yamaha TX81Z OS Version 1.6 EPROM Firmware Upgrade KIT

What’s Included:

• One brand new, ESD-safe ROM upgrade chip programmed with Yamaha TX81Z OS version 1.6, the final official firmware issued by Yamaha.
• If requested, a download link to the TX81Z service manual for your personal reference.

Please note: The Yamaha TX81Z synthesizer itself is not included—this listing is for the 1.6 ROM upgrade chip only.

How to Check Your Current Firmware Version:

• With the TX81Z turned off, hold both Left and Right cursor buttons and switch the unit on. The ROM version will appear on the display. Turn off the TX81Z when finished.

Noteworthy Details About the 1.6 Upgrade:

• The OS firmware has been updated from v1.5 to v1.6 to address several MIDI-related bugs. (See full technical listing below.)
• Preserves Yamaha's authentic service notes for buyer reference.
• When a voice number parameter change message is received in Performance Edit mode, if D01 is the voice number that is received after preset voice number C32, switching is done incorrectly -- not to D01, but to i01.
• POLY / MONO messages in Single mode with OMNI do not switch as expected; same for channels 1-16.
• Portamento time CC message is recognized regardless of basic channel setting.
• Key assign “altr” mode controller logic bug fixed.
• Out-of-range MIDI parameter changes now trigger proper error messages on the LCD.

Important Memory & Backup Notes:

• Replacing the OS ROM chip does not restore or erase user presets; however, if your internal CR2032 battery is weak or dead, user memory can be lost after power off. If your TX81Z doesn't retain patches, battery replacement is recommended before or after installing the new firmware.
• To avoid data loss, back up your custom patches and settings with a MIDI SysEx bulk dump before upgrade. Instructions can be found in the service manual or online guides.

Compatibility:

• Compatible with all Yamaha TX81Z units designed for a socketed ROM chip (IC location may vary). If your chip is soldered or your unit differs, professional desoldering may be needed.

Important Installation Warning: Always unplug your TX81Z before opening the case. Align the notch on the ROM chip with the notch on the socket before installing. Incorrect ROM installation (for example, reversed orientation) will destroy the chip and can damage your TX81Z. If in doubt, please ask first.

Installation Guidance:

• Work in a static-safe environment and use proper anti-static precautions.
• If you’re not confident about installation, do not power on your synth. Send a clear photo of your install for verification—I'm happy to help.

Made to Order – Quality Assured

All ROM upgrades are programmed and verified in an ESD-safe environment and ship in static-protective packaging. Only new, high-grade, recently manufactured chips are used.

Protect Your Investment with High-Quality Components:

• All chips are legitimate, brand new, and thoroughly tested for long-term reliability.

Purchase with Confidence!

Questions before or after purchase? Send me a message—I'm happy to help!