Legacy Ultra MonoBloc User manual

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Registration
3. Owners Record
Setup
4. Unit Connections
6. Unit Care
Technology
7. Designer’s Note
9. Specifications

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The model and serial numbers are located on the rear of the unit. Record
these numbers in the spaces provided below. Refer to them when calling
upon your dealer regarding this product.
Model No. _______________________________
Serial No. _______________________________
Date of purchase: _________________________
Thank you for selecting a Legacy Audio System. Please take a few
moments to read this brief manual to insure maximum benefit from your
electronic system.

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To properly install the Ultra MonoBloc in your audio system, follow these
brief steps.
1. Location
To provide for adequate ventilation you should allow at least a couple of
inches on each side of the amplifier. Because of its large power supply,
the amplifier produces a local magnetic field that may be picked up by low
level circuitry such as preamplifiers, turntables, and the like. For this
reason you should also provide about a foot of space between your
amplifier and these low level components.
2. Power Connections
Be certain all associated equipment is turned off before making any
connections. Position your amplifier as near the final location as possible
while leaving sufficient access to its rear panel connectors. Check that the
amplifier is turned off by pressing the rocker switch on the left side. Insert
the power cord into the AC LINE INPUT on the back panel and then
connect it to an appropriate power source.

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3. Input Connections
Signal input from your preamplifier is made through one gold plated RCA
(unbalanced) or one XLR (balanced) type connector.
Do not use both RCA and XLR connectors at the same time as they
will load each other improperly.
4. Output Connections
Signal output to your speaker is made through heavy duty gold plated five
way binding posts that are doubled up to provide bi-wiring capability. Be
sure of correct speaker phasing by matching the + on the amplifier to the +
on the speaker and the - on the amplifier to the - on the speaker.
5. Electrical Protection
The AC line voltage is preset at the factory but may be changed by your
Legacy dealer. Also, there is an AC line fuse and internal rail fuses, but
these too should be changed by your Legacy dealer since the failure of
these parts may indicate a further problem.

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If you wish to clean your Ultra MonoBloc, use diluted ammonia based
window cleaner. Do not use any abrasive cleaners or chemical solvents.
Take care not to damage the aluminum faceplate, since aluminum is a
medium hardness metal and can be scratched by the careless use of tools
during the installation.
The Ultra MonoBloc may overheat and the finish may fade if exposed to
direct sunlight or intense heat sources for prolonged periods.
Save your box and packing material; they may be necessary for moving or
shipping the unit for servicing by the factory.

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The Legacy Ultra MonoBloc is the most exquisite amplifier we have built.
A balanced interconnection is provided to take advantage of the greater
noise rejection it provides. Differential voltage gain throughout provides
exceptional rejection of external noise and contributes to the inherent DC
stability of the circuit. This allows direct coupling without servo circuitry.
The unit also uses output followers operating without feedback.
The front end is designed to provide a slew rate of 50 V/µs without
entering Class B operation as is common in many other designs. This, in
combination with excellent high frequency design, insures linear operation
at high speed. The supplies take a very direct approach to high
performance. A top quality 1700 VA toroidal transformer and 80,000 µF of
total capacitance with very low ESR and inductance are used in the power
supply. Each Monobloc uses 36 individual output transistors with a linear
bandwidth of 10 MHz.

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The current stage is capable of producing peak currents in excess of 90
Amperes. This offers a degree of linearity and speed which is not matched
by other designs when producing only a fraction of this current. This is
achieved by the implementation of several distinct circuit features.
The bias section is designed to produce a precision transition with no
abrupt changes in distortion or output impedance. This “Precision Bias”
technique yields seamless performance regardless of the complexity of
the load impedance. With such linearity and bandwidth no overall
feedback correction is used. One advantage of this is a high degree of
immunity from interactions with complex speaker loads or cables.

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Bandwidth: CD to -3dB @ 100 kHz
Distortion: < .05% (actual type .025)
Gain: 26dB
Power Supply: 1700VA toroidal transformer and eight 10,000 µF
100 volt capacitors
Noise: More than 100 dB referenced to rated output.
Input Impedance: 50 k ohms unbalanced
Output Impedance: 0.08 ohms from 20Hz to 20 kHz
Slew Rate: 50 Volts/microseconds
Rated Power:
600 Watts/channel, 20 Hz to 20 kHz, into 8 ohms
1200 Watts/channel, 20 Hz to 20 kHz, 4 ohms
Dimensions:
Faceplate: 17”W x 5 1/2”H
Chassis: 16 3/4”W x 6” H x 14”D
Weight: 58 pounds
Current Capability: 90 Amperes peak

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© 2003 Legacy Audio
150 Locust Street.
Macungie, PA 18062
Phone: [phone]
Fax: [phone]