Absolare Hybrid Stereo Amplifier User manual

ABSOLARE Hybrid Stereo Amplifier
User Manual

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ABSOLARE Hybrid Stereo Amplifier User Manual 1.2

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ABSOLARE Hybrid Stereo Amplifier User Manual 1.2
Contents
1. General Description ...............................................................................................................4
2. Safety Issues and Warnings ...................................................................................................4
3. Unpacking and Placement .....................................................................................................5
4. Installing the Tubes................................................................................................................6
5. Connecting the Cables ...........................................................................................................7
5.1. Power cables ...................................................................................................................7
5.2. Signal Cables....................................................................................................................7
5.3. Speaker Cables ................................................................................................................7
6. Operating the Unit .................................................................................................................8
6.1. General Operation...........................................................................................................8
6.2. SEL Switch........................................................................................................................8
6.3. GAIN Switch.....................................................................................................................8
7. Troubleshooting and Maintenance .......................................................................................9
8. Technical Specifications.........................................................................................................9

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ABSOLARE Hybrid Stereo Amplifier User Manual 1.2
1. General Description
The Absolare Hybrid Stereo Amplifier is a tube input / solid state output hybrid
design, dual-mono stereo amplifier. The single ended tube input section is inspired
by the Absolare Preamplifier using two 12AU7/ECC82 (or compatible) tubes. The
output section is all solid-state.
2. Safety Issues and Warnings
- Be sure the voltage setting of the unit matches the applied voltage to power
input. Operating voltage is fixed and must only be changed by an authorized service
agent.
- Do not connect unbalanced subwoofer input terminals to speaker outputs!
Absolare Hybrid Stereo Amplifier has a balanced output stage. Neither of the
speaker output terminals should be connected to ground. Doing so may permanently
damage the amplifier. Please consult your dealer about correct subwoofer
connection.
- This Amplifier is not bridgeable.
- Do not short circuit the speaker terminals. The output is protected for short
circuits, but speaker damage may occur from electrical pulses when the connectors
touch to each other.
- Do not touch tubes while operating. Tubes are extremely hot devices and
contain very high voltages.
- Do not open bottom covers. There are no user serviceable parts inside the unit.

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ABSOLARE Hybrid Stereo Amplifier User Manual 1.2
3. Unpacking and Placement
After opening the top cover of the box, remove the upper layer of hard foam material.
You can then lift the Hybrid Stereo Amplifier from its box cradling it with the cloth that
is underneath the chassis. Retain the cloth and all packing materials for future use.
The Hybrid Stereo Amplifier may become very hot during operation. You should
always place it on support feet and leave at least 2 inches (5 cm) clearance above
the Amplifier to allow sufficient ventilation.
The Hybrid Stereo Amplifier is designed to be supported by separate support feet. It
does not have support feet fixed in place. Feet can affect the sound quality
significantly. Feet must be positioned underneath the Amplifier in direct contact with
the aluminum base plate –not the leather clad MDF covers. There are three areas
where the aluminum base plate is exposed through openings in the leather clad MDF
bottom plate. You can use either three or four feet.
After the Amplifier has been placed in its final position, it can be lifted in turn to locate
the support feet –firstly lifting the back (for 2 feet) and then the front (for 1 or 2 feet)
to be placed underneath the chassis. Adjusting their position will also affect the
sound to varying degrees, depending on the type of rack, location or interaction with
other equipment. For the most situations, the arrangement as shown in the diagram
below is a good starting point.

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ABSOLARE Hybrid Stereo Amplifier User Manual 1.2
4. Installing the Tubes
There are two 12AU7 (ECC82) twin triode tubes in the input stage. Do not remove
the tubes while the unit is operating.
12AU7 / ECC82 tubes have one missing pin acting as a correct positioning key.
Align the missing pin with the missing hole in the tube socket while inserting.

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ABSOLARE Hybrid Stereo Amplifier User Manual 1.2
5. Connecting the Cables
5.1. Power cables
AC power input is via a standard IEC inlet socket. Operating voltage must only be
changed by an authorized service agent.
The quality of the power cable will affect the sound quality accordingly.
5.2. Signal Cables
You can connect 1 unbalanced and 1 balanced source devices at the same time.
The selector switch is in between the input connectors.
5.3. Speaker Cables
Speaker binding posts can handle spade lugs, banana plugs or bare wire.
Polyethylene knobs are chosen instead of metal ones to reduce extra conductor
mass and eddy currents. Do not overtight them, the higher friction of the
polyethylene should safely secure the cables in place.
You can connect any speaker with 4Ω impedance or above. The Hybrid Mono
Amplifier can maintain output specifications into impedance variations down to 2.5Ω.
CAUTION: Negative (black) speaker binding posts are not at ground level
electrically. Do not connect them to chassis ground, or to each other in any way.

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6. Operating the Unit
6.1. General Operation
Before turning on the Absolare Hybrid Stereo Amplifier, be sure that all tubes are
installed and all cables are connected securely.
After turning the Amplifier on, the power indicator LED on the front face plate will
start to blink. You will not hear any sound until the indicator LED stops blinking to
illuminate continuously which indicates all the capacitors are charged and internal
voltages are stabilized.
The Absolare Hybrid Stereo Amplifier will be ready to operate approx. 40 seconds
after turning on the power but attain full performance after 15 to 30 minutes.
There is a built-in thermal protection. If the output devices become too hot, output
power is reduced. It is heard as distorted sound.
Hence much of the voltage gain occurs in tube section, overall sound quality and
character is very dependent of the tube choice.
There is requirement for matching tubes to optimise performance. You can try
different types / brands of tubes in the left and right positions. The 12AU7 is a twin
triode tube, it is better to use tubes with closely matched internal triodes.
6.2. SEL Switch
Selects the active input connection, XLR or RCA connector. The unselected input is
terminated with a 620Ω resistor.
You may hear a loud pop noise when switching capacitor coupled tube sources due
to DC charge/discharge currents.
6.3. GAIN Switch
At LOW position, gain switch attenuates the sound level by -6dB. This compensates
for actual pro-level balanced sources. It can also be used to enable wider volume
adjustment range with highly sensitive speakers.
The gain setting affects both channels equally.

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ABSOLARE Hybrid Stereo Amplifier User Manual 1.2
7. Troubleshooting and Maintenance
Surface of the unit is dirty
- Clean with a slightly damp cloth.
No power light
- Check AC line voltage
- Check the main fuse
Sound level is too high or too low
- Check gain selector
Power light is on, tube heaters are
glowing, but no sound
- Check the input cables, speaker cables
and source
- Check input selector
- Check if tube(s) are defective
Noise / hum in the sound
- Check grounding of power, input cables
and source
If the problem is persistent, contact your nearest ABSOLARE dealer.
8. Technical Specifications
- Input Sensitivity: 1.0 Volts @ Hi-gain setting, 2.0 Volts @ Low-gain setting
- Tubes: 2 x 12AU7 (ECC82 or compatible)
- Inputs: 1 RCA unbalanced + 1 XLR balanced
- Input impedance: 10 kΩ RCA input, 20 kΩ XLR input
- Output Power: 275 Watts @ 4Ω, 175 Watts @ 8Ω
- Speaker impedance: 4 –8 Ω
- Gain: 29 dB @ Hi-gain setting, 23 dB @ Low-gain setting
- Bandwidth: 20Hz -20kHz within +/- 0.2dB, 15 Hz –30 kHz +/- 1.0 dB
- Dimensions: 38.2 x 64.8 x 20 cm / 15" x 25.5" x 7.9" (W x D x H), excl. feet
- Weight: 33 kg / 73 lbs., net

ABSOLARE USA LLC
40 Pemberton Road, Nashua, New Hampshire, 03063
Phone: [phone]
E-mail: [email protected]
ABSOLARE SERVICE EUROPE
Mozartstraat 157, 1962AL Heemskerk, Netherlands
Phone: [phone]
E-mail: [email protected]

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ABSOLARE Hybrid Stereo Amplifier User Manual 1.2
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