Yamaha DX7mega128 User manual

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Yamaha DX7mega128 Expansion User Guide
* Welcome to *
* DX7mega128 *
1: Introduction
The DX7mega128
1
is essentially a “lite” DX7 SuperMAX+ type expansion. It provides the
following new features:
MEMORY EXPANSION
 4x memory expansion: There are now 128 patches
2
(what Yamaha calls "voices")
arranged in 4 banks of 32. Each patch is directly selectable by standard MIDI Patch
Change messages.
 The Function Settings can be saved as a single global value or on a per-patch basis.
GLOBAL PARAMETERS
 MIDI Transmit Channel: You can set the MIDI OUT channel from 1 to 16. (MIDI IN is
already settable in the Yamaha factory DX7 v1.8 firmware using button Function 8).
 Local On/Off: You can set whether the local keyboard sounds the internal FM sound
engine (or not).
 MIDI Receive in OMNI mode (receives on any/all channels).
PATCH PARAMETERS
 Programmable Keyboard Zone: Each patch can utilize a settable active keyboard zone
(low key to high key) within which the local keyboard sounds the internal FM sound
engine per patch.
 Programmable Patch Volume: Each patch can utilize a volume to even out the DX7
levels when changing patches.
 Voice Stacking: You can stack and detune two or four voices of the same patch. You
then have a choice of 16x1, 8x2, or 4x4 polyphony. The detuning can provide chorus
effect and/or chording and/or octaves (for example).
BUG FIXES
 Includes the fixes for the DX7 Fixed Frequency table bug and also includes the faster
boot.
 [v1.30+] Hardware-selectable MIDI Velocity Offset fixes the stock DX7 velocity issue.
1
The information provided in this document is intended for informational purposes only and is subject to
change without notice. Information may be changed or updated without notice. We may also make
improvements and/or changes in the product(s) described in this information at any time.
2
In this document the term "patch" is used to denote a programmed sound. For some unknown reason back
in the 80's, Yamaha called these "voices". The typical use for "voices" these days is to indicate the degree
of polyphony (how many keys you can hold down at once and get sound for).

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Installation
You are looking at the wrong document. Please refer to the DX7mega128 Installation Guide
available on the www.musictechnologiesgroup.com website.
Manual Conventions
Regarding the LCD, this manual shows the variable part of the LCD content using an underline.
The DX7 itself is not able to underline more than one character, but this convention makes it
easier to visualize the changing part of the LCD versus the fixed part.
THIS AREA IS FIXED
AND THIS: CAN CHANGE
Version Check
You can check the version of your DX7mega128 by pressing the brown FUNCTION key and
while holding it down press and hold 16 and 32. You should see a version message such as:
DX7mega128
Version 1.20
or
MIDI Out Vel=+0
Version 1.30
Press the green INTERNAL button twice to escape.
Updates to MIDI (Function Button 8)
The following items are available on button #8 in Function mode:
MIDI Ch In = 1 Settable MIDI Receive channel, or OMNI mode
Local Control=ON Enable/Disable keyboard play of DX7 sounds
SYS INFO UNAVAIL Enable/Disable System Exclusive

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Recommended Initialization
After installing the board, or any time the battery is changed, there can be some random data in
the DX7 RAM. Check and set the Function parameters and load some patch data to begin using
your new DX7mega128:
1. Turn the Internal Memory Protect OFF to enable saving settings and data.
2. Set the expander “Function/Patch” value OFF so that one global set of function data is used
(for now).
3. Initialize the expander Function data using the “Function INIT?” Menu option (choose Yes).
4. Set the expander active Memory Bank to 1.
5. Load a set of patches from cartridge or system exclusive. If the latter is used, then Sys Info
must be set to Available first.
Steps 1 and 5 are standard DX7 user manual stuff. For the other steps you need to read this
entire manual anyway, so take the time to do that and make note of how to perform steps 2, 3
and 4. And if you haven’t read the Yamaha DX7 user manual, well … consider it.

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2: Operation
All of the new operating parameters are accessed using button 12 and/or button 13 in Function
mode. These two buttons take you up and down the list of new Function parameters and the
menu wraps around if you press the same key repeatedly. The DX7 remembers the last activated
Function parameter and it is “live” on the panel (data slider and Yes/No buttons) even in normal
“play” mode.

FUNCTION CONTROL
Memory Bank = 4

FUNCTION CONTROL
Volume Out = 5

FUNCTION CONTROL
Func/Patch= OFF

FUNCTION CONTROL
Func Data INIT?_

FUNCTION CONTROL
MIDI Ch Out = 16

FUNCTION CONTROL
KB Zone Lo = C1

FUNCTION CONTROL
KB Zone Hi = C6

FUNCTION CONTROL
Voice Stack= 2x8

FUNCTION CONTROL
Detune Coarse…

FUNCTION CONTROL
Detune Fine…

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2.1 Memory Bank Selection
Recall that the DX7 has 32 internal patches accessed by pressing the INTERNAL button and
then one of the patch numbers 1 though 32.
The DX7mega128 has four banks of these to make the 128 patches:
Bank 1 Patches 1 to 32 = MIDI patch numbers 1 to 32.
Bank 2 Patches 1 to 32 = MIDI patch numbers 33 to 64.
Bank 3 Patches 1 to 32 = MIDI patch numbers 65 to 96.
Bank 4 Patches 1 to 32 = MIDI patch numbers 97 to 128.
To select a Bank and patch from the front panel, press Function button to activate Function
Control. Using button 13 (Next Menu) or button 12 (Previous Menu), locate the menu item
Memory Bank:
FUNCTION CONTROL
Memory Bank = 4
You can then select which bank is active using the Data Slider or + / - buttons. The next patch
you select will come from the memory bank you chose. Even when you return to play mode (say,
by pressing INT and/or a patch number), this function remains active so you can continue to
change banks with minimal button pressing. Please also see the caveat below.
A convenient way to select banks from your now expanded memory is to leave the most recently
selected MEMORY BANK button "live" in Function mode. When you return to "play" mode the
data entry control remains active on the memory bank parameter thus making easy to access all
128 voices.
When you select a patch via the front panel, its patch number (1 through 128) will be transmitted
on the DX7's MIDI OUT.
Another way to select patches is through MIDI IN. The patch numbers correspond to the patch
numbers 1 to 128 in the table above. That is, on receipt of a MIDI Program Change message on
the correct MIDI channel, the correct bank and patch will be activated. Note that if you have
cartridge installed it will be played in place of Bank 2.
Each bank must be saved or loaded individually using a cartridge or over MIDI.
CAVEAT: Keep in mind that this operating rule is the same for any function button. That means
for example, if the most recently selected Function is Volume, you could accidentally turn the
sound off without knowing the reason.
2.2 Patch Volume (can be saved per-patch)
FUNCTION CONTROL
Patch Volume = 7
The overall volume can be set to a value from 0 to 7. This allows you to trim the patch volume
levels for the appropriate impact when playing live or switching from patch to patch.
This data can be saved per-patch if the Function Data Per-Patch setting is turned on.

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2.3 Function Data: Per-Patch or Global
This setting determines whether or not there is one global set of Function Parameters or if the
Function Parameters are set on a per-patch basis.
FUNCTION CONTROL
Func/Patch= OFF
The traditional setting for the original DX7 is that there is one global set of Function Parameters.
You can continue this tradition by setting Func/Patch (function per patch) to OFF. If you would
prefer to save Function data with each patch, then set Func/Patch to ON.
In addition to the regular DX7 function parameters
 Poly/Mono, Portamento, Aftertouch, Pitchbend, Modulation Wheel and Breath Controller
the new parameters
 Volume, Active Keyboard Zone and Voice Stacking
are saved with each patch when this is enabled. If you don’t utilize Function/Patch, then the
Volume setting isn’t really of much use since it will be global and there is already a dedicated
analog Volume slider.on the DX7.
2.4 Function Data: Initialization
This sets the Function Data to a known good state. This should be performed after board
installation and whenever dubious function data is found (such as might happen after loading
from a ROM or RAM cart or Sys Ex receive or changing the battery)
FUNCTION CONTROL
Func Data INIT?_
To initialize the Function Data, simply locate this menu item and press the +/Yes button.
2.5 MIDI Transmit Channel (global parameter)
All of the MIDI settings are global, in that they are NOT saved with a patch. They are saved
overall for the synthesizer.
FUNCTION CONTROL
MIDI Ch OUT = 1
The MIDI note data, patch changes, etc. will be transmitted on the MIDI Channel specified here.
Using the Data slider or the Yes/No buttons, select the MIDI OUT channel you want, the range is
1 to 16.
Note: The MIDI IN channel is established via the standard DX7 Function button 8.

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2.6 Active Keyboard Zone (can be saved per-patch)
This function specifies the zone or region of the keyboard that will control the DX7 by setting a
Keyboard Low key and a Keyboard High key. It uses two screens:
FUNCTION CONTROL
KB Zone Lo = C1
FUNCTION CONTROL
KB Zone Hi = C6
The first screen sets the lowest note that will activate the internal sound. The second screen sets
the highest note that will activate the internal sound. The range is from C-2 to G8.
The value is chosen using the Data Slider or the + / - buttons.
Played notes outside the Active Key Zone will still be sent out on the MIDI transmit channel.
This data can be saved per-patch if the Function Data Per-Patch setting is turned on.
2.7 Voice Stack and Detune (can be saved per-patch)
The last three screens are used to set the Voice stacking mode and detuning of the extra voices.
DX7mega128 allows you to stack a DX7 patch in modes of 16x1 (standard, no stacking), 8x2 or
4x4. Each of the extra voices can have its pitch offset. Thus you can create not only
chorus/flange type effects, but also octave and chording.
FUNCTION CONTROL
Voice Stack= 2x8
To utilize this feature, the first step is to select which Voice Stack mode you would like. There are
up to three additional voices, or copies of the patch, available. The additional voices are called
"2", "3" and "4". You access each in turn by pressing the same function button over and over
again.
If you are in mode 16x1, then only the original Voice1 is used. All Detune settings are ignored.
If you are in 8x2 then the original Voice1 and Voice2 (coarse and fine) are used. The Detune
settings for 3 and 4 are ignored.
If you are in 4x4 then all voices tunings are used.
Stack Voice Coarse Pitch: Here you can set the coarse pitch for each of the three additional
voices in semitones from -24 to +24. The modifiable coarse value is the whole number portion to
the left of the decimal point
Voice Stack Mode
COARSE 2=-12.00

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Voice Stack Mode
COARSE 3=- 5.00
Voice Stack Mode
COARSE 4= 7.00
Stack Voice Fine Pitch: Here you can set the fine pitch for each of the three additional voices in
cents from .00 to .99. The modifiable fine value is the fractional portion after the decimal point.
Voice Stack Mode
FINE 2=-12.00
Voice Stack Mode
FINE 3=- 5.00
Voice Stack Mode
FINE 4= 7.00
If you want a negative fine adjustment alone, start with -0.00 and then adjust the Fine setting.
This data can be saved per-patch if the Function Data Per-Patch setting is turned on.
MIDI Note-On Velocity Fix [v1.30+ only]
The stock DX7 keyboard has a restricted range on the maximum MIDI Note-On velocity it
transmits. If you strike a key extremely hard you can get a maximum velocity out of 118 ($76
hex). A hardware fix has been included that allows the player to obtain full MIDI Note-On velocity
of 127 ($7F hex) without fear of damaging the keybed.
The DX7mega128 circuit board has a switch, S1, that allows you to change between default (0)
and full velocity (+3) operation. This switch is not intended to be changed on-the-fly with the
power on, but you can try it for an A:B comparison if your patches are backed up.
When the switch is to the right, the setting is +0 (stock). When the switch is to the left, the setting
is +3 (enhanced). Remember, you can verify this setting by doing a Function+16+32 version
check.
Enjoy your updated DX7!
See the MTG web site for more great vintage synth and drum machine goodies.