Dave Benson's DX7 Page

[Picture of DX7II-FD]

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This is a page for the Yamaha DX7 Synthesizer.

Notice: As a result of running this page, I am receiving an unmanageable volume of email asking me for help with various aspects of the DX7. I apologise for not being able to answer all these questions personally. I would like to suggest that you join the email discussion group instead (see below).

Manuals Etc.

  • DX7 (pdf, 2,235,998 bytes)
  • DX7 parts list (html/gif)
  • DX7 circuit diagram (pdf, 1,276,546 bytes)
  • DX7 MIDI implementation (text)
  • DX7 Software 1988 (html)
  • DX7 control panel buttons (pdf, 67,740 bytes)
  • DX7 control panel buttons (gif, 81,744 bytes)
  • DX7 E! card (pdf, 8,189,967 bytes)
  • DX7/DX9 service manual (pdf, 268,508 bytes)
  • DX7IID/DX7IIFD (pdf, 4,305,396 bytes)
  • DX7II E! card (tif files)
  • DX7s (pdf, 3,571,423 bytes)
  • DX21 (pdf, 575,002 bytes)
  • DX27 (pdf, 814,933 bytes)
  • DX100 (pdf, 695,601 bytes)
  • TX802 (pdf, 2,069,845 bytes)
  • "Special Edition ROM" from Yamaha Canada (pdf, 1,379,144 bytes)

  • How to program the DX7 (article from Keyboard Mag, June 1985, pdf, 1,195,279 bytes)
  • Interview with John Chowning (html)
  • Also see my Maths and Music page; these course notes contain a discussion of Bessel functions and FM synthesis, as well as many other interesting and occasionally relevant topics.


    Email discussion group (and list archive )
    Patches in many formats
    Loading Patches into your DX7
    Initializing the DX7
    Patch Editors/Librarians (PC, Mac, Atari, Amiga)
    Grey Matter E! Card
    The Battery (and how to change it)
    Hooking your DX7 up to a PC
    Yamaha's Phone Number
    (and how to get a physical copy of the DX7 manual or a new battery)
    Internal diagnostics for the DX7
    What are the different DX7 models and their features?
    Where do I get one?
    Other Links

    Email discussion group

    St in Norway has now taken over the running of the Email discussion list. Information can be found here


    Go here for ManyMIDI Products' DX7/TX7 Sound Libraries.

    Here is a collection of public domain patches for the DX7 in several formats:

  • SYX files (1,177,600 byte tar file)
    These are system exclusive files, each containing one bank of 32 voices.
    These are complete with sysex headers.
    The original factory patches are here as rom1a.syx - rom4b.syx.

  • dx7patch.zip The same, zipped into one big file (475,707 bytes)

  • dx7patch.wrk This is a file in Cakewalk format, containing the same system exclusive banks. Select "load to local disk" before clicking (941,485 bytes)

  • RAW files (1,290,240 byte tar file)
    These are the same system exclusive files, stripped of their headers. This is how they originally came from the site at ucsd.edu.

  • Robert Rogers has kindly made a single Unisyn file for Mac users, containing the above patches with the duplicates removed. This is a Binhexed, stuffit file (554,975 bytes)

    David Brown has kindly made a zip file of the same patches in voyetra format (556,812 bytes). This is for use with Voyetra programs "Sequencer Plus" and "SideManDTX" editor librarian. The file format for both programs is identical. Unzip them to your C:\voyetra\banks\ location and they are ready to run.

  • Galaxy 2.1 Banks for Mac (click here for a possibly out of date local copy; 705,126 bytes)

  • all-syx.zip Some more SYX files, zipped up (107,415 bytes)

  • DX7EXTRA.ZIP Yet more patches in SYX format (462,742 bytes)

  • deckard.zip (523,506 bytes) This is a zip file of 263 banks of SYX files, taken from Yamaha's UK site (they did not originate there, and Yamaha apparently has no objection to their distribution). They were put into the usual Sysex format by Jack Deckard

  • The same (610,008 bytes) in Voyetra format, again zipped up

  • The zicweb site also has some patches for DX7; a local copy can be found here. The file dx7.zip consists of 302 banks of 32 sounds for DX7 (pure sysex) with tools. Most of them are the same as the ones from ucsd.edu above, but there seem to be a few which do not appear there. The file dxsq.zip consists of 301 of these banks in MIDI QUEST format. The file addit.exe is a small program to add sysex headers to banks which don't already have it. The file dx2sy.exe is a small program to convert DX7 banks to SY77 format.

  • Translator from DX7 patches to Csound SCO, by Jeff Harrington; local copy here.

    Click here for the information on the sysex format needed to convert from raw files to sysex files.

    Click here for a C program to convert from raw files to sysex files.

    Click here for a C program to convert the resulting sysex files to MIDI files.

    See also the section books for patches from the "600 patches" book.

    Loading Patches

    If you're looking for a way to send SYSEX files from a PC to a DX7, there is a very cheap fully featured commercial sequencer with SYSEX capabilities called Power Tracks Pro Audio available for US$29 from PG Music Inc, 266 Elmwood Ave, Suite 111, Buffalo NY 14222, USA. Tel 1-800-268-6272, 604-475-2874, Fax 604-658-8444,

    In order to send the patches to your DX7 from your PC, you will also need an MPU401 compatible MIDI interface, and MIDI cables to hook the interface to your DX7. For more details, see below under Hooking your DX7 up to a PC

    In case you've forgotten what you need to do to your DX7 to make it able to receive incoming SYSEX messages, you need to set "memory protect internal" off, and then just send the data from your computer.

    If you have a Grey Matter E! card installed, it's slightly more complicated: Press "function", then "operator select" twice to select the "memory" page, push button 31 twice (Memory Protect Internal) and then "off". This disables the memory protect. Then press "function", then "operator select" four times to select the "keyboard control" page, push button 2 (Midi in filters: SYSEX) and then "on". This enables SYSEX data transfer. You are now finally ready to send the data from your computer.

    On the DX7II-d, you need to turn memory protection off (Button #14), set the device number on the keyboard to the device number under which the sysex was originaly saved (button #32), and set "MIDI IN" to "normal" (button #29). If you don't do this third step, you get no error message and no hint of what is wrong, but the keyboard just doesn't accept the sysex data.

    Initializing the DX7

    A frequently asked question is the following: "How do I initialize my DX7 so that I recover the original patches?"

    Unfortunately, the answer is, "You don't". The information for the original patches is not stored in non-volatile memory. So if you want to recover the initial patches, you have two options. Either use the ROM cartridges which came with the DX7, or if you don't have these, download them (see patches) and use your computer to send them to your DX7 (see Hooking your DX7 up to a PC).

    Patch Editors/Librarians

    Look here for Winsysex and the DX7 voice editor to use with it.

    A DX7 patch librarian for the Mac is available from Takashi Suzuki's DX7 page or from here.

    A DX7 patch librarian for the PC (dos) from Zorch Brotherz Software called DXLib is available by going here and looking under Editors/Librarians, or from here.

    A patch librarian for the PC (windows) called SoundLib, which supports the DX7 among others is available from here. The free registration code, donated by the author, can be found here.

    A shareware patch librarian called Midilib for Windows 95 only (not Windows 3.1) on a PC, which supports the DX7 among others is available from here or from here. If you don't have the MFC40 run time libraries, you'll need to pick these up from the same place to run Midilib.

    A DX7 patch librarian for the Atari can be found here or here.

    A number of DX series utilities for the Amiga including a librarian can be found here.

    A summary of the software available for the DX series of synthesizers in 1988 (thanks to Paul Troutman) can be found here.

    Here are 2 Mixermaps for the TX81Z and 2 Mixermaps for the TX802 that Dorian May designed for Steinberg's Cubase VST for the Mac.


    Go here for a freeware program by Manuel Op de Coul to tune a DX7II/TX802, SY77/TG77/SY99/VL-1/VL-7 or TX81Z/DX11/DX27/DX100 to any scale you like.

    The Grey Matter E! Card

    The "E!" card is an add-on enhancement board for the DX7 and DX7II.
    Grey Matter can be contacted at the following address:

    Grey Matter Response, Inc.
    4340 Scotts Valley Drive
    Suite C
    Scotts Valley, CA 95066
    Phone: 408-461-2121
    Fax: 408-461-2120
    Please note, however, that they have announced that they no longer have any E! cards, for the DX7 or for the DX7II.

    A zipped file of the E! demo files disk for the DX7II can be found here.

    The official word is now that Grey Matter has run out of E! boards for the DX7 as well as for the DX7II/FD, and do not intend to make any more.

    For the E! MIDI specification, look here.

    The DX7 version gives:

  • extra patch memory (with function data for EACH patch)
  • optional ROM sounds from GMR, allowing 576 patches in a DX7
  • patch mapping
  • master contoller functions
  • transmission on two midi channels
  • stacking of sound (makes it thicker but only 8 note poly)
  • ...and more...

    The individual list of MIDI enhancements is too great to list here.
    Click here for a complete list of functions.

    The DX7II/FD version {includes all of the above?} and adds:

  • 8 voice multi-timbral capability
  • a sequencer
  • a MIDI monitor
  • a simple, "interactive" player mode

    The Battery

    DX7 synthesizers contain a battery to maintain internal memory when there's no power supplied. Opinions seem to vary as to how long this lithium battery really lasts. Some say three to six years, some say ten to fifteen, and in any case, it depends on how long the keyboard is left turned off. It's important to change this battery when it gets low -- not just to protect the internal storage of your keyboard, but also to avoid battery leakage, which could seriously damage your keyboard's circuitry.

    The process involves fully disassembling your DX7, desoldering the old battery, and soldering in a new one. Complete instructions are available by clicking here. Further information here.

    Hooking your DX7 up to a PC

    Here are some hints on hooking your DX7 synthesizer up to a PC.

    There should be no problem with trying to drive the DX7 from your PC, if you have a working sequencer and an MPU401 compatible MIDI interface configured correctly. This is usually a standard half-length (or sometimes full length) card, so you will need a spare card slot in your PC. The card connects with the DX7 via standard MIDI cables. The things to note are:

  • The DX7 does not have an on board sequencer, so it is impossible to "record" music directly with it unless you have it connected to a computer running some sort of sequencer software.
  • The DX7 only responds to channel 1. It is monotimbral, which means that it will only play notes using one "patch" at a time, but polyphonic, so that it can play up to 16 notes at a time from that patch.
  • You do need to have the appropriate MPU401 driver installed using your Windows control panel.
  • Make sure you have MIDI out from your MPU401 card connected to MIDI in on your DX7.
  • If you also have MIDI in from your MPU401 card connected to MIDI out on your DX7 then you need to worry about MIDI loops - there should be a setting on your sequencer for breaking MIDI loops.
  • Note that the DX7 will only output volumes in the range 0-99, not the full range of 0-127. This is a design limitation in the original design of the DX7. There is a box by Anatek called the "Pocket Curve" (reviewed in Feb '92 Keyboard Magazine) which will sit in the MIDI chain and do the conversion. The E! card also solves the problem.
  • If you do have everything set up correctly, try loading a simple sequence into the sequencer and start it going.
  • For instructions on sending patches to your DX7 from your PC, look under Loading Patches.
  • These days, many sound cards have MIDI interfaces built into them. However, the adapter on the back of the sound card is usually a game port rather than a MIDI connector. It is possible to buy for about US$30 or so an adapter which plugs into a game port, and has MIDI in and MIDI out connectors. One point to watch: these adapters come in two varieties, according to whether the MIDI connectors are male or female. If your DX7 is very close to your computer, you may be able to get away with plugging the male variety directly into the DX7. It is more likely, however, that you will need to attach the DX7 via MIDI cables, in which case you will need the female variety. It is also possible to get short double female adapters for about US$5 each to connect a MIDI cable to a male MIDI in/out.

    Yamaha's Phone Number

    Tel: (714) 522-9011
    Tel: (888) 892-6242
    FAX: (714) 522-9832

    Phoning this number is the easiest way to get hold of a copy of the DX7 manual [DX-OM] for US$15 or a new battery [PC900040] for US$12.54. They also still have ROM 1/2/3/4 [NB826850/6860/8290/8300] for around US$150 each, but I'd recommend picking them up from the public domain patches above for free instead.

    Note also that Rogue Music has a large library of manuals which they are willing to photocopy for a small charge.

    Internal diagnostics for the DX7

    The procedure is to hold down the function key and then press keys 16 and 32 simultaneously.

    If your machine has the E! card installed, this procedure will tell you the version number rather than initiate the internal diagnostics.


    Howard Massey: Complete DX7
    Amsco Publications, 1986.

    Mark Vail: Vintage Synthesizers
    Miller Freeman Books
    ISBN: 0879302755.

    J. Chowning and D. Bristow: FM Theory and Applications
    Yamaha Music Foundation, 1986
    ISBN 4636174828
    (Written for use with a DX series synthesizer, explains basic theory of FM synthesis, Bessel functions, and so on)
    Note: the graphs for J10 and J11 on page 176 have apparently been accidentally interchanged

    Yasuhiko Fukuda: Yamaha DX7 Digital Synthesizer
    Amsco Publications, London/New York/Sydney/Cologne 1984
    ISBN (UK) 0-7119-0653-X

    Lorenz Rychner: The Classic Yamaha DX7
    Alexander Pub, 1987
    ISBN 0-9390-6705-6

    Yamaha Easy DX7 : A Complete Guide to the Dx Synthesizer
    Hal Leonard Pub Corp, 1986
    ISBN 0-8818-8452-9

    600 Voices for the DX7
    Amsco Publications, London/New York/Sydney/Cologne 1986
    ISBN (US) 0-8256-2499-1 (UK) 0-7119-1166-5
    The patches can be found here (Thanks, Tim Conrardy). The extensions are .snd, but they are just ordinary sysex files.

    What are the different DX7 models and their features?


    The original (also known as Mark I)


  • a 6 operator 32 algorithm FM tone generator
  • a single bank of 32 voices.
  • 61 full sized keys


  • monotimbral, no true splits or layers
  • monaural (not stereo)
  • velocity range 0-99, not 0-127


    The 'new generation' of DX synthesizers (Mark II). This model has everything the DX7s added plus:
  • 2-channel tone generator, which allows bi-timbral effects including stereo, splits, and layers.
  • each of the two tone generators can be controlled independently via MIDI on separate channels, making the DX7IID do the work of two DX7s keyboards
  • larger LCD display and an extra LED voice display for the second channel's voice number


  • only 8 simultaneous notes are available in dual voice mode

    Dimensions: 999 x 85.8 x 333.7 mm (39-3/8" x 3-3/8" x 13-1/8")
    10.5 kg (23.1 lbs.)
    Original List Price: US$2195.00


    Identical to the DX7IID with the important exception that it has:
  • a 720K (formatted) 3.5" floppy drive

    999 x 85.8 x 333.7 mm (39-3/8" x 3-3/8" x 13-1/8")
    11.2 kg (24.7 lbs.)
    Original List Price: US$2495.00


    A 'cost effective' alternative to the DX7II line of synthesizers.
    It uses the same enhanced voices as the DX7II, but is monotimbral and produces monaural sound. It has everything the DX7 has plus:
  • 44.1kHz 16-bit DAC for improved freq. response and dynamic range
  • 2 banks of 32 voices (instead of 1).
  • 32 performance presets.
  • fractional level scaling (in 3 key groups)
  • RAM4 cartridge slot
  • 16-key multiple LFO timing
  • adjustable range on the pitch envelope generator
  • micro-tuning (each key can be separately tuned)
  • random pitch to simulate intonation of acoustic instruments
  • aftertouch-based pitch-bending
  • 16 simultaneous notes with reverse priority
  • greatly enhanced MIDI implementation


  • monotimbral, no true splits or layers are possible.
  • monaural

    999 x 85.8 x 333.7 mm (39-3/8" x 3-3/8" x 13-1/8")
    10.5 kg (23.1 lbs.)
    Original List Price: US$1495.00


    DX7 in a rack


    DX1 was essentially a double DX7 with two complete DX7 instruments packed into single, 73 key, wooden piano keyboard. Display with lots of LEDs to show algorithm and operator settings, and plenty of dedicated buttons provide de luxe interface


    The same internal workings and almost the same interface as the DX1, packed in a lighter (portable) package. 76 plastic keys, but metal case. Pretty exotic (not very many of them around)


    The DX9 is monotimbral, 16 voice polyphonic, and only has 4 operators to play with. The worst thing about the DX9 is that it's not velocity sensitive.


    This is 8 DX7s in a rack
    There are also TX216 and TX416 with 2, resp. 4 DX7s in a rack
    Separate audio output for each unit
    PSU and rack box has MIDI switcher built in. It has MIDI in/out/through on it and you can select which of the 8 modules you wish to receive MIDI from.


    This is a DX7II in a rack with extra features
    For example it is 8 part multitimbral with 2 voices each


    4 operators synths, not compatible with DX7 patches

    Where do I get one?

    Since the DX7 has not been in production for a number of years, your only hope is to get a second hand one. They appear from time to time on ebay (online auctions), so you could try looking there. The price for a plain DX7 seems to be around US$300-$400 at the moment. If it has an E! card, or if it's a DX7II, etc., expect to pay a little more.

    Other Links

  • Takashi Suzuki's DX7 page
  • Future Music's DX7 page
  • The Yamaha Zone
  • The official Yamaha page
  • Synth Museum's DX7 page
  • The Patchman DX7 patch page
  • Chris's DX7/TX7 page
  • FM alive, home of the DX manager


    We have only just begun to explore the breadth and depth of the sonic landscape. Musical instruments as we know them occupy a small corner, but we are slowly learning to venture out into the wide open spaces. The DX7 and FM synthesis, in their day, opened up a new horizon. We recognise this because some of the sounds have been so overused as to have become cliché. When we read Shakespeare we experience the same feeling, but that should stop us neither from reading Shakespeare nor from making the sounds of the DX7 a part of today's music. This page is mostly concerned with the more technical aspects of the DX7, but we should never lose sight of the final product. Make music, make it well, and make it with love.

    And vice versa.

    © Dave Benson 2010.