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Performance Manual: Diagnostics

Battery Check

The programs in the Chroma's memory are maintained by two "AA" size batteries on the computer board. Periodically check the battery voltage by pressing [SET SPLIT], then [6]. If the cell reading in the DATA READOUT is less than 2.5 volts, have your service center replace the batteries. As a precaution, always make a backup cassette tape of your programs in the event your batteries run down before you get to the service center.

Error Messages

When the Chroma is first turned on, or when the [AUTO TUNE] switch is used, each of the 16 oscillators and filters are checked and tuned. if any channel fails to function or cannot be tuned properly, an error message will appear in the DATA READOUT.

There are eight dual channel boards in the Chroma labelled "0" through "7". When a defective channel is encountered during the tuning process, the channel board is turned off automatically. The Chroma will operate normally, but with two less channels. Subsequently pressing [AUTO TUNE] will not affect the disabled board. The Chroma's computer is instructed to ignore this board until a power-up or reset occurs.

For example, the message "Err    0" means that channel number "0" is defective and has been disabled. If there is no error, the DATA READOUT will show a "P" or an "L" as the first letter in the display.

Occasionally, a channel may be just slightly out of tune due to exposure to temperature extremes. To retest a channel (to verify that it is indeed defective) press [SET SPLIT], then [50]. This resets the Chroma. This will cause the Chroma to go through its initialization sequence which tests and tunes all boards. If the same error message occurs, contact your local service center.

Checking for Disabled Boards

If at any time you wish to see if any of the channel boards have been disabled, press [SET SPLIT], then [8]. If any channels are turned off, the DATA READOUT will display "Err" followed by the channel number. If the DATA READOUT does not appear to have changed, then all boards are functioning properly.

Manual Disable

If a problem should develop on a channel board during performance and is not automatically turned off, it can be manually turned off. First play the keyboard until the offending note is heard. Before playing another key, press [SET SPLIT], [7]. This will cause the last channel board to be played to be turned off. The DATA READOUT will display "Err" followed by the channel number. To turn the channel back on, press [SET SPLIT], [50] (reset), or turn the Chroma off and then on again.


Under the control panel of the Chroma is a mechanical "tapper" which strikes the control panel whenever a switch is pressed. Even in loud music situations, the pressing of a switch can be felt, confirming that the switch has been closed. To turn off the tapper, press [SET SPLIT], [9]. To turn the tapper back on, press [SET SPLIT], [9] again.

NOTE: Other "hidden" [SET SPLIT] features are described in the programming manual [see Hidden Functions].

Cassette Errors

If during a cassette load operation faulty data is received, the Chroma will halt the tape deck and display "Error". See the Cassette Interface section of this manual for more information.


Symptom Possible Problem Cure
No lights when Chroma is turned on. No power. Check power cord and switch, verify that the outlet has power.
No audio output. Audio output not connected to MONO OUTPUT. Put plug in MONO OUTPUT, remove all plugs from the 4 AUDIO OUTPUTS.
Volume pedal is used in current program. Set the volume pedal to maximum, or unplug it.
VOLUME slider down. Raise VOLUME slider.
No program in "current program". Select a different program, or reload cassette, and then select a program. (Also, check battery level.)
PROGRAM NUMBER display goes out and Chroma will not play. Computer interruption has occurred. Turn power off, then on again.
Cannot change programs. Right panel in [PARAM SELECT] or [COPY] mode. Press [PROG SELECT].
Cannot change parameters. Not in [PARAM SELECT] mode. Press [PARAM SELECT].
When editing, PARAMETER CONTROL slider has no effect. Wrong [EDIT] switch selected. (e.g., [EDIT B] selected, [EDIT A] required.) Try other [EDIT] switch, or both [EDIT] switches should be on.
MONO OUT EQ sliders do not affect the 4 AUDIO OUTPUTS. Normal. MONO OUT EQ sliders only affect the MONO OUTPUTS.
[STORE] does not work.. LOCK/UNLOCK switch is in the LOCK position. Put LOCK/UNLOCK switch in the UNLOCK position.
Notes are out of tune. Channels need tuning. Press [AUTO TUNE].
Oscillator B is deliberately detuned in program. Press [PARAM SELECT], [4]. Change detune value using PARAMETER CONTROL slider.
[SAVE ALL] produces short bursts of sound. Cassette is in "save programs with spaces" mode. Put LOCK/UNLOCK switch in the LOCK position.
Cassette doesn't halt after [LOAD] or [SAVE]. Wrong cassette mode. Press [SET SPLIT], [10].
In LINK mode, the MAIN or LINK programs are too low in volume. Link balance set wrong. Move PARAMETER CONTROL slider to correct balance.
Levers do not work. Not in program. Select different program, or edit program to assign lever functions.
Volume pedal does not work. Not in program. Edit program to assign volume pedal.
No "tap" felt when switch is pressed. Tapper disabled. Press [SET SPLIT], [9] to enable the tapper.