ETI Sound Systems, INC US-4000 Front Panel Controls, Blue illuminated strips, Signal Indicators

US SERIES AMPLIFIERS THE BEAUTY OF POWER

FRONT PANEL CONTROLS

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1.Rack Mounting pointS Points to bolt your amplifier into a rack.

2.Air Vents

US-Series amplifiers are cooled by two rear-mounted fans (US-1200 has one fan) and open cell foam filters mounted behind the front vents.

CAUTION: Never block the front or rear vents and keep them clean at all times.

NOTE: Periodically clean the foam filters using a vacuum cleaner to avoid dust from blocking the vents. If the filters become too dusty, it may decrease your amplifier’s ability to dissipate and remove heat efficiently. If the filters become too dusty and too difficult to clean externally, you can access the filters and remove them for cleaning. Refer to the cleaning procedure later in this manual.

3.Blue illuminated strips

These two blue illuminated strips glow when your amplifier is turned ON.

4.Channel 1 and channel 2 LEVEL controls

Use these 21-position detented controls to adjust the output levels of Channel 1 and Channel 2. When the LEVEL controls are set fully counter-clockwise, the signal is attenuated by more than 80dB (marked -∞). When the LEVEL controls are set fully clockwise, the

signal is amplified with maximum gain. When the LEVEL is set fully clockwise, the amplifier produces its rated output power at a 4 Ohm load with +4dBu (1.23Vrms) signal applied to the inputs. All detents are marked in dBs showing the attenuation of

the output signal with reference to the fully clockwise position.

NOTE: In PARALLEL MONO mode, both of the Channel 1 and Channel 2 LEVEL controls are used to adjust the signal level for their respective channels. The signal should be routed only to the Channel 1 input in this mode.

NOTE: In BRIDGED MONO mode, only the Channel 1 LEVEL control is used to adjust the signal level. The signal should be routed only to Channel 1’s input in this mode.

5.SIGNAL Indicators

These green LEDs will illuminate indicating that a signal is being received through the input and that the signal is being amplified. There are three LEDs on each channel: SIGNAL, -20dB and -10dB.

6.CLIP Indicators

These red LEDs will illuminate at the clipping threshold. If the CLIP LEDs light frequently, you are overloading the amplifier, causing gross distortions on the outputs. Heavy clipping is bad for both your speakers and amplifiers and should be avoided.

8 B-52 US Series Professional Power Amplifiers - Instruction Manual