JL Audio HD750/1-Open Box, Acceptable but Missing part Used

HD750/1 Features:

• JL Audio HD Series Monoblock Class D Amplifier
• *RMS Power Rating (11V-14.5V):
• 4 ohms: 750 watts x 1 chan.
• 3 ohms: 750 watts x 1 chan.
• 2 ohms: 750 watts x 1 chan.
• 1.5 ohms: 750 watts x 1 chan.
• Class D, switching type with patented Single-Cycle Control technology
• Pulse width modulation-regulated switching power supply
• LED power (green), protect (red) and low impedance (amber) indicators
• Removable Power/Ground and Speaker connectors
• Brushed aluminum finish chassis
• Compact, stackable chassis design
• Black powder-coated, gasketed cover
• RealSink: Vertical, cast alloy fins effectively dissipate heat
• Advanced Thermal Rollback protection system
• R.I.P.S. - Regulated, Intelligent Power Supply
• Single Cycle Control - high-fidelity, full-range class D
• Compares the real PWM waveform and then corrects it in each and every cycle
  (over 400,000 times per second)
• 80% efficiency at 1/2 rated power for the whole amplifier, including its power supply
• 60% less current draw than a typical Class A/B car amplifier of equal power
• Less generated heat, smaller chassis than a similarly powerful Class A/B design.
• Noise-killing, highly flexible differential-balanced inputs
• 1 Pair of Buffered preamp RCA outputs for daisy chaining the audio signal
• Speaker level inputs via RCA (JL Audio XD-CLRAIC2-SW required and sold separately
• Remote bass level input (JL Audio HD-RLC required and sold separately)
• Optional stacking equipment for HD amplifiers: JL Audio HD Stack Kit
• Selectable input voltage/sensitivity:
• Low level: 200mV - 2V
• High level: 800mV - 8V
• Selectable output polarity, "Phase": 0/180°
• Selectable State-variable slope: 12 dB/octave Butterworth or 24 dB/octave Linkwitz-Riley
• Selectable infrasonic filter, "Subsonic": Defeatable or 30 Hz
• Selectable filter modes: Low-Pass or High-Pass, Defeatable
• Cutoff Freq. Range: Continuously variable: 50 - 500 Hz
• Total Harmonic Distortion: <0.03% @ 4Ω (Average at 1kHz)
• Signal to Noise Ration:
• Referred to Rated Power: 111 dBA
• Referred to 1 Watt: 82.2 dBA
• Frequency response: 6 - 8,000 Hz (+0, -1 dB)
• Damping Factor: >500 @ 4Ω/50 Hz, >250 @ 2Ω/50 Hz
• Recommended fuse rating: 60A x 1 (inline, not included)
• Dimensions: 10.74"L x 7.85"W x 1.93"H
• **4 gauge OFC power and ground wiring is recommended for installation. Contact us for information regarding a discount on select amplifier kits from our website when purchased together with this amplifier. Click Here for our contact information.
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• *If you connect a load higher than 4Ω nominal, power will drop by half with every doubling of impedance above 4Ω stereo. If you connect a load lower than 1.5Ω nominal, the amplifier protection circuitry activates a "safe" mode which reduces amplifier power to protect the circuitry from failure (the LED status indicator on the control panel will light up amber to indicate that this has happened). See page 14 for details.
• **We do not recommend the use of "copperclad aluminum wire" or "CCA" wire because this wire is significantly less conductive than pure copper wire. Only use pure copper power wire, such as JL Audio's Premium Power Wire. Tinned copper wire (silver color) is acceptable as the tin-plating is only a very minor component of the wire.
• **The HD750/1's "+12 VDC" and "Ground" connections are designed to accept 4 AWG power wire. 2 AWG or 1/0 AWG pure copper wire is recommended for any power wire run longer than 72 inches (180 cm). This larger wire should be reduced to 4 AWG using a distribution block within 36 wire inches (90 cm) of the amplifier's "+12 VDC" connector. For runs shorter than 72 inches, 4 AWG pure copper power wire is acceptable