Features

Overview: The Hertz SP 4.900 4-channel amplifier features Advanced D-Class (ADC) technology to deliver high-end performance and efficiency. It features a heavy-duty aluminum chassis with an IP55 rating against dust, dirt, humidity, and water ingress. The SP 4.900's ultra-compact size makes it ideal for motorcycles, sports cars, and behind-the-seat installations in trucks.

CEA-2006-A Power Output: The SP 4.900 is compliant with the CEA-2006-A Amplifier Power Standard, which makes it easy for consumers to compare amplifier power specs from one brand to another. The amplifier's CEA-2006-A ratings include:

• RMS Power (4Ω, 1% THD+N, 14.4 volts): 145 watts x 4
• S/N Ratio (ref. 1W output): 81 dBA

Hertz Power Output Specs: Hertz publishes the following power output specs (RMS Output Power, 14.4 volts, THD 1%):

• 4 Channel: 160 watts x 4 (4Ω)
• 4 Channel: 250 watts x 4 (2Ω)
• 3 Channel: 160 watts x 2 (4Ω) + 500 watts x 1 (4Ω)
• 3 Channel: 250 watts x 2 (2Ω) + 500 watts x 1 (4Ω)
• 2 Channel: 500 watts x 2 (4Ω)

Universal Speakers Simulator (USS): The SP 4.900 features Hertz's Universal Speakers Simulator (USS) technology built into it. USS is a dynamic load circuit that presents a speaker channel with impedance low enough to keep an OEM head unit/amplifier from muting its output, but not low enough to cause over-current or heating problems. This makes the SP 4.900 amplifier ideal for OEM integration.

Turn-On: The Hertz SP 4.900 amplifier offers two methods of being activated, depending on the type of input signal being used:

• DC Offset: This method automatically powers the amplifier on and off when an audio signal (or lack of one) is detected on the speaker-level inputs. This is especially helpful when connecting the amplifier to an OEM radio. It eliminates the need for running a remote lead from the head unit to the amp.
• REM: If connecting the amplifier with RCA (low-level) input signals, a remote turn-on wire must be run from the head unit to the REM IN wire on the amplifier for activation.

Amplifier Controls: The versatile Hertz SP 4.900 has a full array of filters and controls to help you configure your audio system for maximum performance. All controls are located on one end of the amplifier, under a removable cover, and include the following:

• Gain (x2): Two rotary controls let you match the input of the amplifier to the output of your head unit. The amp will accept either line-level or speaker-level inputs. The sensitivity range is 0.6V (600mV) to 6V (line-level) or 2.2V to 22V (speaker-level). There are separate Gain controls for Channels 1/2 and Channels 3/4.
• Input Level: A 2-way switch gets set to either HI (USS) or LO depending on the input signal type (RCA or speaker-level).
• Input Select: A 2-way switch (2CH/4CH) determines if the four amplifier channels will be fed signals from all four RCA input connectors or from just two of them.
• Xover (x2): Channels 1/2 and 3/4 each include a 3-way crossover switch for selecting Full, LP, or HP for each. A corresponding set of Freq dials let you select a cutoff frequency from 50Hz to 5000Hz.
• Bass Boost: Channels 3/4 include a Bass Boost dial that lets you add up to +8dB of boost @ 45Hz, letting you add extra punch if running a subwoofer.
• LED Indicators: A Power LED on the control panel will light Green when the amplifier is powered On. A Protection LED will light Red if the amp over-heats or sees a short-circuit.

Connections: All of the SP 4.900 amplifier wiring connections are made through attached 8" wire harnesses terminated in Molex connectors. The power/ground and speaker output harnesses both include additional 16" harnesses with matching connectors on one end and have bare-ended wire on the other end.

• Power/Ground: The power and ground harness includes three 14-gauge ground wires and three 14-gauge power wires. The power wires can be combined and connected to a larger power wire for running to the battery; a 4 AWG amplifier wiring kit is recommended and is sold separately. The three ground wires can be combined and connected to chassis metal or connected to a larger ground wire.
• Fuse: The SP 4.900 does not include any internal or external fuses. A 50A fuse (sold separately) should be placed within 18" of the battery on the +12V power wire.
• Speaker Outputs: An 8-pin harness provides the four sets of bare-ended, 14-gauge speaker outputs.
• RCA & Speaker-Level Inputs/Remote In: Two stereo RCA inputs are provided for connecting an aftermarket or factory head unit to the amplifier. The RCA connectors provide the input for either low-level (RCA) or high-level (speaker) signals. Four RCA-to-speaker wire adapters are included that plug into the RCA jacks and feature set-screw connections for bare wire on the other end. With the Input Level switch set to LO, the inputs will accept a signal between 0.6V and 6V; with it set to HI, the inputs will accept a signal between 2.2V and 22V. The RCA input harness also includes a blue Remote Input wire for connecting to an aftermarket head unit's remote output, when using RCA low-level input signals.

Specifications:

• Power Supply: 11-15 Volts DC
• Idling Current: 1.1A (on); 0.03 mA (off)
• Consumption (2Ω, 14.4V Max Musical Power): 50A
• Remote In: 6-15 Volts DC / 9mA
• DC Offset Remote Turn-On: 3.5-7 Volts DC
• Frequency Bandwidth (-3dB): 10Hz to 35kHz
• Distortion - THD (1kHz at 4Ω): 0.02%
• S/N Ratio (A-weighted at 1V): 105dBA
• Damping Factor (1kHz at 4Ω, 2Vrms): 200
• Dimensions: Width: 8.853", Height: 1.936", Depth: 5.150"
• Weight: 4.74 lbs.