Power ON/OFF Switch
When the power is turned ON, the program which
was selected immediately before the power was
turned OFF will be re-selected. Due to the safety
muting circuit, no sound will be produced by the
SPX90 for a few seconds after the power is turned
Input Level Control (0 ~ 10)
Regulates the level of the input signal. Set the IN-
PUT LEVEL control while watching the INPUT LEVEL
meter. The seven LED meter segments should not
all be continuously on when an input signal is ap-
plied, as this will result in input amplifier overload
and distortion. When the INPUT LEVEL control is set
to "8" on the scale, the input/output gain is 1
(unity). A setting of "10" increases gain by about
Input Level Meter
This easy-to-read LED level meter is a visual aid to
setting appropriate input levels. Generally, the best
input level setting will produce continuous lighting
of the lower green LED segments, while the upper
red segments flash only occasionally.
Memory Number LED
This LED display shows the number of the current-
ly selected program. Memory numbers 1 through 30
contain factory-preset effects (ROM). Memory
numbers 31 through 90 can be used to store edited
versions of the preset effects (RAM).
LCD Program and Parameter Indicator
This high-contrast Liquid Crystal Display indicates
the effect name and parameter data value.
Selects successive effect parameters. Pressing this
key sequentially calls the programmable parameters
within the currently selected effect program. Once
the desired parameter has been selected, the
PARAMETER INCREMENT/DECREMENT keys are
used to change the value of that parameter, thereby
modifying the effect. The parameters available for
each program are different: refer to the parameter
chart on page 24.
Parameter Increment/Decrement Keys
These keys are used to change the value of a
selected parameter. Press the increment key (up ar-
row) to increase the value, or the decrement key
(down arrow) to decrease the value.
Balance/Output Level Key
Adjusts proportion of effect signal to direct signal.
Pressing this key alternately causes the current
balance and output level values to be displayed on
the LCD. The Parameter Increment/Decrement keys
are then used to adjust the displayed values.
Stores any edited preset effect in a selected RAM
memory position (31 ~ 90).
Memory Increment/Decrement Keys
These keys select any desired memory number to
call a specific program or store an edited program
in the user memory area. The selected memory
number is shown on the MEMORY NUMBER display.
When a new memory number is called, the
MEMORY number display will flash until either the
STORE or RECALL function is activated.
Press this key to recall the program that resides in
the selected memory number.
Multi-purpose key accesses MIDI control functions,
facilitates program title editing and sets footswitch
memory control range. See pages 8 and 9 for details.
Foot Trigger Key
When this key is pressed and its LED is ON, the
footswitch connected to the Memory/Trigger jack
functions as a foot trigger for the GATE and FREEZE
programs, rather than for memory selection.
When this key is pressed, the effect signal is shut
off and only the direct signal will be output. Direct
signal level is affected by the INPUT LEVEL control
Memory/Trigger Footswitch Jack
Facilitates remote memory selection via optional
footswitch. The range of memory locations to be
recalled by the footswitch can be set with a Utility
program. When the foot trigger function (above) is
ON, the footswitch connected to this jack acts as
a trigger footswitch rather than memory control. Use
of a Yamaha FC5 Foot Controller is recommended.
Bypass Footswitch Jack
Facilitates foot control of the BYPASS function
described above. A Yamaha FC-5 Foot Controller is