GR BASS GR 700+ User manual

USERS
MANUAL

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User manual purpose
This user manual is dedicated to the use of the
bass amplifier GR 700+.
The manual includes the following information:
General information (technical data and packa-
ging);
Description of the amplifier’s functions.
All the informations described on this user manual
are verified.
The manufacturer reserves the right to update or
modify their product without any notice.
PACKAGING AND STORAGE
Packaging
GR 700+ is packed in a special cardboard box.
The box contains the amplifier GR700+, power sup-
ply cable and the user manual.
Trasport
Please handle the box with care. A specific position
during the transport is not required.
Storage
Please keep the amplifier in a dry and ventilated
place. Ideal storage conditions: Temperature within
-20C and 40C, Humidity 20% to 80%.

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Product disposal
Please follow the disposal instruction issued by
your local council.
In accordance with European Directive 2002/96 /
EC, all electrical and electronic products should be
disposed by specific collection facilities appointed
by the government or the local authorities.
DECLARATION OF CONFORMITY
The product complies with the following European
directive:
2006/95 / EC - Electrical Safety
2004/108 / EC - Electromagnetic Compatibility
2011/65 / EU - Limited use of certain hazardous
substances in electrical and electronic equipment
A full copy of the declaration of conformity is avai-
lable from the manufacturer.
The manufacturer is not responsible of any dama-
ge due to an improper use of the product.

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Dati tecnici
MAIN FEATURES
• 2 Speakon/jack output
• XLR DI Out
• Tuner Output
• Headphone output
• Send return
• Aux in
• 9V DC output, 250mA
• Gain
• Bass, middle and treble
• Middle frequencies switch
• Subsonic filter
• DI/Headphone volume
• Led VU Meter
• Protection circuits to avoid overheating and
Electric power overload
DI and Headphones output and tuner out are
always active even if no speaker is plugged into the
speakon outputs.
It is possible to use the amplifier with no cabinet
connected, using with headphones or as a DI.
TECHNICAL FEATURES
POWER:
RMS 700 W @ 1 % THD+N, 20 Hz – 20 kHz, 4Ω
DYNAMIC RANGE: 117dBA
Parameters of nominal distortion output:
a) TDH+N: - 0.005 % @ 1 W (4Ω, 1 kHz),
0.0008 % @ 50 W (4Ω, 100 Hz)
b) CCIF IM distortion = 0.0003 %, 10 W, 4Ω,
18.5 kHz / 1 kHz
Low output impedence: 6mW
Total Efficiency: 84 % @ 700 W, 4Ω

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CONTROLS DESCRIPTION
FRONT PANEL CONTROLS
1. Input Jack
Input jack for your bass. We suggest to use a good
quality cable to obtain the best audio performan-
ces.
2. -10 dB Button
On “-10dB” position, the button attenuates the input
signal to the preamp (use only with active PU or
high input signal instrument).
3. Aux IN
3.5mm jack Auxiliar input to connect an external
audio device
4. GAIN control knob
To adjust the input signal amount of the pre-amp.
5. MID-Eq button
To select the middle frequency cut between the
following values: 400 Hz e 800 Hz ≈.
6. Bass Knob
To increase or reduce the bass frequencies.

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7. Mid knob
To increase or reduce the mid range frequencies.
8. High knob
To increase or reduce the high frequencies.
9. SUBS Filter button
Subsonic filter switcher for the woofer protection.
The subsonic filter eliminates the frequencies under
22Hz. It does not modify the audio signal and redu-
ces the woofer range.
10. DI-HEAR KNOB
DI and headphones volume. The headphones volu-
me is amplified compared to the DI. Even if you put
on the minimum level, the audio signal is still on in
the headphones although it is very low.
11. Master knob
Master volume of the amplifier.
12. Mute button
Turn off the amplifier output. The activation of this
mode turns on the red LED on the left of the button.
The tuner-out is still on.
13. Hear output
3.5mm plug for headphones.
14. Operation LED
Green = normal operation.
Orange = high level of the input signal (clip).
15. Vu-Meter
A 20 LED bar indicates the audio signal pitch.

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REAR PANEL CONTROLS
1. Power plug IEC (230V - 115V
IEC plug for power supply connection The GR700+
can be powered with a voltage of 230V or 115V.
The supplied cable is equipped with a ground wire.
For safety and security reasons, never unplug the
ground wire from your equipments.
2. Power switch
To switch on and off your amplifier.
3. 9V output
9V DC output to connect external equipment (we
recommend to connect 4-5 pedal effect maximum).
The polarity is center positive.
4. Tuner-out
6.35 mm jack output to connect a tuner. This output
is always active even if the mute-mode is on.
5. Return
6.35mm jack plug to connect an external effect’s
output.

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6. Send
6.35mm jack plug to connect an external effect’s
input
7. DI output
XLR plug
8. Speakon outputs
It is possible to use a 6.35 mm jack. We recommend
to use a 2 poles speakon connector Never use a
6.35 jack guitar cable to connect your amplifier to
your speakers.
9. FAN switch
FAN cooler on and off switch We recommend to
switch off the FAN only at home or in a recording
studio. The failure of the fan’s activation ONLY
determines the heating of the GR700+ case, which
is actually a heat sink. The case increases its own
temperature and decreases the internal electronics.
The failure of the fan’s activation and prolonged
use in extreme weather conditions could activate
the overheating protection system of the GR700+.
In this unlikely case, please activate the fan and
wait few seconds until the amplifier come back to
the normal working status.
10. PRE-POST DI button
Allows you to choose the type of signal to be sent
to the DI output DI: PRE EQ or POST EQ.

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11. Dot-Bar button
Allows to choose the front VU-METER display mode
between “dot-mode” and “bar-mode”.
GND Lift
The DI out is very accurate and noiseless so there
will hardly never need to deactivate the GND LIFT.
If you like it you can do so by opening the lid and
removing its jumper.

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WARRANTY CONDITION
The warranty covers a period of two years. The
warranty covers any defects in material or wor-
kmanship under normal use during the warranty
period. Any shipping cost to/from the repair service
centre is the customer’s responsibility. In the event
of an irreparable damage or repeated failure of the
same type, the manufacturer may replace the unit,
within the term of the original warranty. The war-
ranty does not cover parts which may result faulty
due to: - Negligence or careless use - Improper
installation and maintenance - Tampering made by
unauthorized personnel. - Damages that might not
be related to manufacturing defects.
The manufacturer accepts no responsibility for any
damage due to persons, animals or things, as con-
sequence of the failure to comply all the installation
requirements and / or use indicated in this user
manual.

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Note

via Nino Bixio 182 70043 Monopoli (Ba) > tel.: [phone]
[e-mail] > www.grbass.com > P.IVA: 07558880725