Why Choose Crutchfield?
Great gear and expert advice
Our experts help you pick the ideal gear for your needs.Meet our advisors
Free tech support for the life of your gear.Read about our one-on-one expert help
You may return items that are complete and like new for any reason within 60 days.See the details of our return policy
Earn one point for every dollar you spend and use those points to save on future purchases.Get full details on Crutchfield Rewards
Deep discounts on car installation gear
We offer vehicle-specific installation instructions, dash kits, wiring harnesses, and speaker accessories at deeply discounted prices with car stereo and speaker purchases. Available for most vehicles.Learn more
Trusted since 1974
Our customers have trusted us with their business, and they’ve helped us win awards for our service.Check out our most recent awards
The manufacturer’s warranty always applies.See more details
75W x 4 Car Amplifier
Item # 037A4601Q | MFR # A4601Q
This item is no longer available.
Our take on the Audiobahn A4601Q by Crutchfield's Robert Ferency-Viars
Hit the road to intense sound with an Audiobahn amplifier. Lightning-fast MOSFET power supplies pump the power to your speakers for crisp, accurate reproduction. Make your full-range speakers sing with the 4-channel A4601Q amplifier. Its 75-watt RMS output is enough juice for almost any system. Or bridge two channels and feed your 4-ohm subwoofer 210 watts of power.
Audiobahn puts the sound control in your hands. Variable high-pass and low-pass crossovers make for versatile sound-tuning. The 18 dB bass boost adds a serious punch to the low end, while the subsonic filter blocks power-sucking inaudible low frequencies.
The digital voltmeter lets you keep an eye on power levels. The built-in cooling fan kicks on when the amp is powered up and stays busy pulling the heat out of the amp to maintain safe operating temperatures.Details:
- 75 watts RMS x 4 at 4 ohms
- 105 watts RMS x 4 at 2 ohms
- 210 watts RMS x 2 bridged output
- 2-, 3-, or 4-channel output
- Tri-way capable (Tri-Way crossover required)
- MOSFET power supplies
- requires 8-gauge power and ground leads wiring and hardware not included with amplifier
- high-pass (50-750 Hz)/low-pass (50-120 Hz) crossovers, 18 dB/octave
- selectable 18 dB bass boost at 50 Hz
- variable (20-50 Hz) subsonic filter
- preamp outputs
- cooling fan
- cobalt blue illumination
- digital voltmeter
- 13-11/16"W x 2-1/4"H x 12-3/4"D
- 1-year warranty
What's in the Box:
- Chrome-plated 4-channel amplifier with two 20-amp blade fuses
- One 1/8" Allen wrench
- One 3/32" Allen wrench
- Four 7/8" mounting screws
- 1 Pair of white gloves
- 1 Audiobahn window sticker
- Operating instructions
- Product registration and warranty book
Features and Specs
|RMS Power Output (Watts x Channels)||
75 x 4
|Peak Power Output (Watts x Channels)||N/A|
|Power at 2 Ohms (Watts x Channels)||105 x 4|
|Bridged Power (Watts x Channels)||210 x 2|
|Minimum Impedance Bridged||4|
|Minimum Impedance Unbridged||2|
|Best Frequency Response||10-40kHz Hz|
|THD at Rated RMS Power||0.02%|
|Signal to Noise Ratio||100 dB|
|Low-Pass Crossover Frequency||50-120 Hz|
|Low-Pass Slope (dB/octave)||18 dB|
|High-Pass Crossover Frequency||50-750 Hz|
|High-Pass Slope (dB/octave)||18 dB|
|Bass Boost||18 dB|
|Bass Boost Frequency||50 Hz|
|Fuse Rating||20 x 2|
|Speaker Level Inputs||No|
|Preamp Outputs||1 pair|
|Parts Warranty||1 Year|
|Labor Warranty||1 Year|
Class A/B MOSFET Power Amplifier: This is a Class A/B amplifier that uses MOSFET devices for its amplification stages and power supply.
High Gloss Chrome-Plated Finish: This amplifier has a high-gloss chrome-plated finish on the top and on all sides. A pair of white cotton gloves is included with the amplifier to prevent finger-print smudges when handling and mounting the amp.
Digital Voltmeter: On the top of this amplifier is a digital voltmeter with cobalt blue illumination. The interior circuit board illuminates as well.
Cooling Fan: There is a built-in cooling fan on the top of this amplifier, which is activated whenever the amplifier receives a signal from the remote turn-on lead. If the remote turn-on lead is connected to your radio, then the cooling fan will run whenever your radio is turned on. The amplifier will shut down if the internal temperature reaches 158 degrees F.
Variable Subsonic Filter: A subsonic (infrasonic) filter allows you to filter out extremely low bass frequencies that may rob power from frequencies that the system can reproduce without distortion. Use of the infrasonic filter allows better amplifier efficiency and better audible sound. The subsonic filter in this amplifier is continuously variable from 20Hz to 50Hz.
Soft-Start Circuitry: The amplifier automatically turns on a few seconds after you turn your vehicle's ignition switch to ACC or ON. The power indicator on the side of the amplifier lights when the amplifier is on.
Terminals: The amp has nickel-plated, heavy-duty set screw terminals.
- Thermal: shuts off the amp when the operating temperature is too high
- Input Overload: shuts off the amp as a result of low voltage or over-voltage
- Short Circuit: shuts off the amp due to speaker or DC short
Left Side of Amplifier
- Front and Rear Variable Gain Controls: these rotary controls allow you to match the input sensitivity of the amp to the particular source unit you are using
- Front and Rear Subsonic Frequency Controls: these rotary controls allow you to filter out unwanted bass frequencies. The subsonic filter in this amplifier is continuously variable from 20Hz to 50Hz.
- Front and Rear High-pass Frequency Control: these rotary controls allow you to adjust the frequency of the high-pass crossover from 50Hz to 750Hz
- Front and Rear Low-pass Frequency Control: these rotary controls allow you to adjust the frequency of the low-pass crossover from 50Hz to 120Hz
- Front and Rear Crossover Switch: lets you select high-pass, low-pass or full-range operation for the speaker outputs
- Front and Rear Bass Boost Switch: lets you select either OFF or +18dB, centered at 45Hz
- Front and Rear Subsonic Frequency Switch: lets you turn the subsonic filter on or off
Right Side of the Amplifier
- Line-In: two sets of left and right RCA input jacks
- Line-Out: RCA preamp output jacks, which allow you pass full-range signals from this amplifier to another amp in a daisy-chain configuration.
- Speaker Terminals: four +/- pairs of nickel-plated set screw terminals (each terminal is 0.25" wide)
- BATT (power): nickel-plated set screw terminal (accepts 4-gauge wire)
- GND (ground): nickel-plated set screw terminal (accepts 4-gauge wire)
- REM (remote turn-on): nickel-plated set screw terminal (terminal is 0.31" wide)
- Fuses: two 20-amp fuses
Continuous Power Rating (measured at 14.4V):
- Bridged Into A 4-Ohm Load: 210 watts x 2
- Per Channel Into A 2-Ohm Load: 105 watts x 4
- Per Channel Into A 4-Ohm Load: 75 watts x 4
Our Product Research Team
At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.