Gemini PA-7000 Stereo Amplifier User Manual


 
(3)
INTRODUCTION:
Congratulations on purchasing a GEMINI model PA-7000 rack
mountable preamplifier. This state of the art unit includes the latest
features backed by a three year warranty. Prior to use, we suggest
that you carefully read all the instructions.
CAUTIONS:
1. All operating instructions should be read before using this equipment.
2. To reduce the risk of electrical shock, do not open the unit. There are
NO USER REPLACEABLE PARTS INSIDE. Please refer servicing to a
qualified service technician.
3. Do not expose this unit to direct sunlight or to a heat source such as a
radiator or stove.
4. This unit should be cleaned only with a damp cloth. Avoid solvents or
other cleaning detergents.
5. When moving this equipment, it should be placed in its original carton
and packaging. This will reduce the risk of damage during transit.
6. DO NOT EXPOSE THIS UNIT TO RAIN OR MOISTURE.
7. DO NOT USE ANY SPRAY CLEANER OR LUBRICANT ON ANY
CONTROLS OR SWITCHES.
CONNECTION.
Be sure the POWER (1) switch is in the OFF position. All connections
must be made with all equipment OFF. For best sound, use only high
quality RCA cables when hooking up equipment to the PA-7000. Make
sure that all cables are pushed in securely. Connect the OUTPUT LINE
(22) jacks (TRS and XLR) of the PA-7000 to your amplifier(s). Plug your
microphone into the MIC (5) jack on the front panel of the PA-7000.
Plug your headphone into the PHONE (11) jack on the front panel. Plug
your turntable into the PHONO (16) jacks and attach the ground wire
from the turntable to the GND (23) screw. Plug your CD player into the
CD (17) jacks. Plug your tuner into the TUNER (18) jacks. Any other
line level output device (such as a mixer) may be connected to the AUX
(19) jacks. You will require two sets of RCA cables to connect your
tape deck to the PA-7000. Use one set of RCA cables to connect the
tape deck’s playback or output jacks to the PLAY (20) jacks on the rear
of the PA-702. Use the other set of RCA cables to connect the tape
deck’s record or input jacks to the REC (21) jacks on the PA-7000.
NOTE: ANY LINE LEVEL DEVICE CAN BE CONNECTED TO THE PLAY (20) JACKS AND THEN
CAN BE ACCESSED BY THE TAPE MONITOR (3) BUTTON.
OPERATION:
1. POWER: Once you have made all source connections to the PA-7000,
and you have made sure that the VOLTAGE SELECTOR (24) switch is
in the proper position, plug the power cord into a power source and
press the POWER (1) button (LED lights).
2. INPUT SELECTION: The INPUT SELECTION (2) switch determines
which input source goes through the PA-7000 to the amplifier. If the
PHONO position is selected on the INPUT SELECTION (2) switch, then
the source connected to PHONO (16) jack on the back panel will be
selected. If the CD position is selected, then the source connected to
the CD (17) jack on the back will be selected.
3. TAPE MONITOR: Pressing the TAPE MONITOR (3) button (the LED is
lit) allows you to hear the playback signal of your tape deck or
whatever you have connected to the PLAY (20) jacks on the rear
panel. Pressing the TAPE MONITOR (3) button a second time (the LED
is off), disengages the tape monitor circuit.
4. MIC LEVEL: The MIC LEVEL (4) control adjusts the volume of the
microphone.
5. MIC JACK: 1/4" microphone input jack (5).
6. VOLUME: Overall volume is controlled by the VOLUME (6) control.
7. BALANCE: Use this control to adjust the relative levels of the left and
right channels. The 12 o’clock position is the point of equal BALANCE (7).
8. TREBLE: The TREBLE (8) control adjusts the relative level of the high
frequencies in the sound.
9. MID: The MID (9) control adjusts the relative level of the mid range
frequencies in the sound.
10.BASS: The BASS (10) control adjusts the relative level of the low
frequencies in the sound.
11.PHONE JACK: 1/4" headphone input jack (11).
12.MONO: When the MONO (12) button is activated (LED is lit), the two
stereo channels are blended together to produce monophonic sound.
This blend minimizes rumble and surface noise in old monophonic
records. Push the button a second time (LED goes out) to get back to
stereo mode.
13.MUTE: Pushing this button reduces the volume of the amplifier output
signal by approximately 20 dB. Pressing the button a second time
removes the muting. The MUTE (13) has no effect on the microphone
volume.
14.LOW CUT:
The output from a turntable usually contains strong but
inaudible impulses at infrasonic frequencies (below 20Hz) due to disc
warps, stylus/tonearm resonance, and vibrations that reach the
turntable. If these are amplified at full strength, they may waste
amplifier power and muddy the sound. The LOW CUT FILTER (14)
attenuates these unwanted signals.
15.LOUDNESS: When pressed, the LOUDNESS (15) button engages a
“loudness compensation” circuit which, at low-to-medium volume,
boosts the bass and treble response.
USING THE GROUND LIFT SWITCH:
Depending on your system configuration, sometimes applying the
ground will create a quieter signal path. Sometimes lifting the ground
can eliminate ground loops and hum to create a quieter signal path.
1. With the unit on, listen to the system in idle mode (no signal present)
with the ground applied (the GROUND LIFT SWITCH (25) in the left
position).
2. Then turn the power off before moving the GROUND LIFT SWITCH
(25). Lift the ground by moving the GROUND LIFT SWITCH to the right,
turn the power back on and listen to determine which position will
provide a signal devoid of background noise and hum. Keep the
GROUND LIFT SWITCH in the ground position if the noise level remains
the same in either position.
CAUTION: DO NOT TERMINATE THE AC GROUND ON THE UNIT IN ANY WAY. TERMINATION
OF THE AC GROUND CAN BE HAZARDOUS.
SPECIFICATIONS:
INPUTS SENSITIVITY/IMPEDANCE
Mic..................................................................................................................................................1mV / 3 Kohms
Phono..........................................................................................................................................3mV / 47 Kohms
Tape,Tuner,CD, Aux..............................................................................................................150mV / 22 Kohms
OUTPUT/IMPEDANCE
Tape Rec....................................................................................................................................150mV / 3 Kohms
Pre Output............................................................................................................................max. 11V / 1 Kohms
TOTAL HARMONIC DISTORTION
Mic.................................................................................................................................................less than 0.02%
Phono...........................................................................................................................................less than 0.04%
Tape,Tuner,CD, Aux...................................................................................................................less than 0.01%
SIGNAL TO NOISE RATIO
Mic................................................................................................................................................more than 70dB
Phono..........................................................................................................................................more than 90dB
Tape,Tuner,CD, Aux................................................................................................................more than 100dB
GENERAL
Frequency Response....................................................................................................5Hz - 30 KHz +0, - 3dB
Bass............................................................................................................................................+/-12dB at 100Hz
Midrange......................................................................................................................................+/-9dB at 1KHz
Treble........................................................................................................................................+/-12dB at 10KHz
Loudness................................................................................................................+9/0/+9dB at 100/1K/10KHz
Mute...............................................................................................................................................................-20dB
Power..................................................................................................................................120V or 230V, 50/60Hz
Power Consumption.....................................................................................................................................15W
Dimensions................................................................................................................483mm x 45mm x 248 mm
19" x 1.75" x 9.75"
Weight.................................................................................................................................................4 kg (9 lbs.)