Troubleshooting; Specifications - Zoom GFX-4 Operation Manual

Troubleshooting

Symptom
No sound or very low
volume
Bypass (mute) mode
cannot be activated
Volume does not
change when
expression pedal is
operated in bypass
mode
Expression pedal on/off
switching is not
performed properly
Oscillation occurs

Specifications

Effect programs 44 (42 effects + ZNR + Amp Simulator)
Effect modules 6 + ZNR + Amp Simulator
Patch memory USER
3 patches x 5 banks x 4 groups = 60
(read/write/store)
PRESET
3 patches x 5 banks x 4 groups = 60 (read
only)
Total 120 patches
Sampling frequency 40 kHz
A/D conversion 20-bit 64-times oversampling converter
D/A conversion 20-bit 128-times oversampling converter
Input Guitar input
Standard phone jack (mono) x 1
(nominal input level -10 dBm)
Pickup select
Normal
Input impedance 510kΩ
(pickup type = passive)
Active
Input impedance 20 kΩ (pickup type =
active)
Check
• Is suitable AC adapter connected, and
power switch set to ON?
• Is instrument connected correctly to INPUT
jack and playback equipment to OUTPUT jack?
• Is shielded cable defective?
• Is amplifier turned on? Are level controls for
instrument and amplifier set to proper values?
• Is GFX-4 set to mute condition?
• Is MASTER LEVEL knob turned down?
• Is expression pedal raised?
• Has unit been switched between program
mode and manual mode?
• Has expression pedal been set to
function as volume pedal?
• Is mono output used (playback system
connected only to OUTPUT MONO jack)?
• Readjusting the pedal may correct the
problem.
• Is high-gain distortion effect used
together with compressor/booster
effect or EQUALIZER?
Make connections as described in "Getting
Connected" and turn power on.
Make connections as described in "Getting
Connected".
Try using another cable.
Turn amplifier on and adjust volume to
proper level.
Cancel the mute condition.
Set MASTER LEVEL knob to proper position.
For some patches, the expression pedal
controls the volume. Set it to a suitable
position.
Switch function is different in program mode
and manual mode. Select correct mode.
Assign volume control function to
expression pedal as described on page 19
and set minimum volume.
With a mono connection, the expression
pedal cannot be used to control the
volume. Connect the playback system to
OUTPUT STEREO jack.
Readjust pedal, as described on page 28.
Reduce parameter values of high-gain
module (gain, tone, level).
Outputs Mono output
Standard phone jack (mono) x 1
(nominal output level -10 dBm, output
impedance 10 kΩ or higher)
Combined line/headphone output
Standard phone jack (stereo) x 1
(maximum output level +4 dBm, output
load impedance 10 kΩ or higher)
Display Original LCD (with backlight)
2-digit, 7-segment LED
Power requirements 12 V AC, 500 mA
(from supplied AC adapter AD-0008)
Dimensions 397 mm (W) x 183 mm (D) x 60 mm (H)
Weight 1.4kg
* 0 dBm = 0.775 Vrms
* Design and specifications subject to change without
notice.
Remedy
29
ZOOM GFX-4