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US Acoustics USX-4085
85W x 4 Car Amp
Item # 235USX4085 | MFR # USX-4085
This item is no longer available.
Our take on the US Acoustics USX-4085
Here's a reasonably-priced solution to the challenge of powering multiple sets of speakers with one amp. The USX4085 multi-channel amp from US acoustics is a rugged, terrific-sounding powerhouse that can drive a variety of speaker combinations. And built-in selectable high-/low-pass variable crossovers on its preamp outputs means you can add another amp, but you won't need to buy a separate component crossover.Details:
- 2-, 3-, 4-channel or Tri-Way output
- 85 watts RMS x 4 at 4 ohms
- 240 watts RMS x 2 in bridged mode
- MOSFET output devices
- 2-ohm stable in stereo
- anti-thump circuit for quiet turn-on
- thermal, short-circuit, and power/ground reversal protection
- gold-plated differential preamp inputs to reject noise
- MOSFET power supply
- 12-200 Hz high-pass crossover (front and rear), 12 dB per octave
- 40-200 Hz low-pass crossover (front and rear), 24 dB per octave
- preamp outputs with selectable low-/high-pass crossover
- THD at rated power 0.01 percent
- 101 dB signal-to-noise ratio
- 35 amp fuse
- 17"W x 2-1/2"H x 9-5/8"D
- 1-year warranty
What's in the Box:
- Blue amplifier with chrome trim and US Acoustics logo w/ a 35-amp blade fuse in chassis; 4 isolation plastic mounting feet; Manual; Warranty registration card with survey
- NOTE: 4 self tapping screws (not included) are required for mounting
Features and Specs
|RMS Power Output (Watts x Channels)||
85 x 4
|Peak Power Output (Watts x Channels)||N/A|
|Power at 2 Ohms (Watts x Channels)||120 x 4|
|Bridged Power (Watts x Channels)||240 x 2|
|Minimum Impedance Bridged||4|
|Minimum Impedance Unbridged||2|
|Best Frequency Response||10-30k Hz|
|THD at Rated RMS Power||0.01%|
|Signal to Noise Ratio||101 dB|
|Low-Pass Crossover Frequency||40-200 Hz|
|Low-Pass Slope (dB/octave)||24 dB|
|High-Pass Crossover Frequency||12-200 Hz|
|High-Pass Slope (dB/octave)||12 dB|
|Bass Boost Frequency||---|
|Speaker Level Inputs||No|
|Preamp Outputs||1 pair Gold RCA|
|Parts Warranty||1 YEAR|
|Labor Warranty||1 YEAR|
Lowpass frequency control: This controls the lowpass frequency for all of the channels set for lowpass operation using the mode buttons. It is variable from 40-200Hz with a 24 dB slope.
Mode buttons: The mode for channels 1 & 2 and channels 3 & 4 an be set to lowpass or flat/highpass. When a full range signal is desired this button is set to highpass/flat and the highpass frequency is set to the "flat" setting which allows all frequencies above 15Hz to pass through.
Highpass frequency: This controls the highpass frequency for channels 1 & 2 and channesls 3 & 4. It is variable from flat to 200 Hz with a 12dB slope.
Gain control: There is a variable gain control for channels 1 & 2 and channels 3 & 4 from 110mV to 8.8V.
Selector switch: This is used to determine what is output through the RCA preamp outputs. It may be set to "low", "1+2" or "3+4". When set to "low", the low pass crossover sets the low pass crossover frequency for the line outputs. Setting the switch to "1+2" allows you to set the RCA output high pass frequency with the channel 1+2 highpass selector (note that this can be set all the way down to flat if required). Selecting "3+4" allows you to set the RCA output high pass frequency with the channel 3+4 highpass selector (note that this can be set all the way down to flat).
Power: When the power is on a green power LED lights.
Protection: There is a red protection LED.
There is a gold plated terminal strip for +12V, remote and ground.
There is a gold plated terminal strip for left and right loudspeakers for channels 1/2 and 3/4.
RCA preamp outputs: There are gold plated stereo RCA outputs.
RCA preamp inputs: There are two pairs of gold plated stereo RCA inputs.
The amplifier uses high current MOSFET devices.
There is a time delay turn-on with muting circuits.
The protection covers reverse polarity, thermal and short circuit.
The amplifier uses high speed, audio-grade components in all low level stages
Power output is at 12.9V
RMS x 2 Ohms: 120 watts x 4
Channel separation: 81 dB
Best frequency response: 10Hz to 30kHz, -.5dB
Fuse: 35 amp blade
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