US60, US90 User Manual
Speaker Connections
The US series amplifiers can be used either as 100V line amplifiers or standard low impedance power amplifiers. These 2
configurations cannot be used together, so decide which method will be used at the start.
100V line systems
For 100V line systems, connect the amplifier to the first speaker in the system using double-insulated speaker wire which has adequate
current rating to handle the total output of the amplifier.
Connect th
e “100V”
output terminal to the positive (+)
connection of the speaker and “COM”
output to the negative (-) connection of
the speaker (14). Connect further speakers in parallel to the first speaker with all positive terminals connected together and all
negative terminals connected together as shown below.
A 100V line speaker system can comprise of many speakers connected together. The determining factor for how many speakers can be
used on a single amplifier is the power rating. For most purposes, it is advised to connect as many speakers as needed with a
combined wattage of no more than 90% of the amplifier’s output po
wer rating.
The terminals of a 100V speaker are connected to a transformer and in some cases, this tran
sformer may be “tapped” for diffe
rent
power ratings. These tappings can be used to adjust the wattage (and output volume) of each speaker in the system to help achieve
the ideal total power of the system for the amplifier.
Low impedance systems
The US-series amplifiers can alternatively provide an output for a single 8
Ω speaker by
connecting the “
8
Ω” output
to the positive (+)
speaker connection and “COM” output
to the negative (-) speaker connection. It is important to ensure that the speaker load is no
lower than 8
Ω and that the power ha
ndling of the speaker is equal to or greater than the output power of the amplifier.
Operation
When all connections to the amplifier are made, turn the MASTER volume control down (1) and switch on the power (4). A power LED
will illuminate at the left side of the audio output indicator LEDs (2).
Play an input signal (line or 100V) into the amplifier to check the system. Turn up the MASTER volume control (1) gradually until the
output is heard through the speakers. The MASTER acts as the overall volume control.
When not being used, turn down the MASTER control before powering down to avoid loud clicks or pops.
Specifications
Model
US60
US90
Output power: RMS
60W
90W
Dimensions
269 x 210 x 44mm
300 x 210 x 44mm
Weight
2.47kg
2.99kg
Power supply
170-264Vac, 50Hz (IEC)
Amplifier: construction
Class D + transformer output
Inputs
Line in (RCA or Euroblock), 100V in (Euroblock)
Line output
2 x RCA (mono)
Speaker outputs
Screw terminals -
100V / 8Ω / COM
Mute
24V relay contacts
THD
<0.4% @ 1kHz
Input impedance
1k Ohms (line)
Input sensitivity
-10dB (line)
SNR
80dB (line)
Frequency response
100Hz - 18kHz
Disposal:
The “Crossed Wheelie Bin” symbol on the product means
that the product is classed as Electrical or Electronic equipment
and should not be disposed with other household or commercial waste
at the end of its useful life. The goods must be disposed of according to your local council guidelines.
Errors and omissions excepted. Copyright© 2021.
AVSL Group Ltd. Unit 2-4 Bridgewater Park, Taylor Rd. Manchester. M41 7JQ
AVSL (EUROPE) Ltd, Unit 3D North Point House, North Point Business Park, New Mallow Road, Cork, Ireland.