Hertz SP4.900 1000W RMS 2000W Peak Amplifier Pre-wired to add amp to 1998-2013 Harley-Davidson® Street Glide



1000W RMS , Class D 2-3-4 channel amplifier
  • Plug-&-Play Kit For Harley-Davidson Street Glides with Factory Headunit
  • Prewired for factory radio harness, also includes power and ground to battery connected to amp
  • Gains and all settings come preset from us.
  • More Features!

10 in stock


Our friends at Hertz have released a game changer for motorcycle audio! The Hertz SP4.900 amplifier has a small footprint, but HUGE output! This is the strongest amp available in its size, packing 160W RMS @4ohm and 250W RMS @2ohm. The SP4.900 gives massive power output with an anstonishingly low distortion rate of .02% thd, making it the perfect option for your Street Glide!

For your convenience, we offer this amplifier pre-wired for factory Harley radios (flash required), as well as the Soundstream models

We have completed all the hard work for you, making this a true plug and play setup! We have pre-set the gains and high pass filters to exactly what they need to be for the radio you have! We’ve also connected the power and ground wires, so all you have to do is plug into the radio harness and run the power and ground wires to your battery, then your system will be rockin’!

See below for technical specs:

Output Nominal Power (RMS) @ 14.4 VDC, THD 1%:
4 Ch: 160 W x 4 (4Ω)
4 Ch: 250 W x 4 (2Ω)
3 Ch: 160 W x 2 (4Ω) + 500 W x 1 (4Ω)
3 Ch: 250 W x 2 (2Ω) + 500 W x 1 (4Ω)
2 Ch: 500 W x 2 (4Ω)
Total Power RMS 1000 W

Hertz ADC
(Advanced D-Class)

SP 4.900 is the first Hertz amplifier featuring the renewed Hertz ADC (Advanced D-Class) output stage, reaching up to 85% efficiency and delivering an impressive power rating of 160 x 4 (4Ω) W RMS or 500 W x 2 (4Ω) W RMS when bridged, with an ultra-compact size of 211.6 (8.3) x 130 (5.1) mm (in.). Being ultra-compact with an impressive power, SP 4.900 is the ideal choice for Motorcycle application and for under-seat in sport cars and behind-seat installations in trucks.

Hertz ADC technology ensures SP 4.900 overtakes the usual ultra-compact amplifier performances, delivering an outstanding 105 dBA S/N Ratio and 0.02% THD specifications, and almost completely eliminating EMI and RFI noise, for peerless sound quality.

This versatility is perfect to drive high power (4Ω) front speakers with a bridged (4Ω) subwoofer.

SP 4.900 is fully protected against overheating and DC outputs, immediately switching in protection mode (red led on) to save your speaker system.

The IP55 certified Aluminum chassis offers maximum protection against humidity and external agents and the absence of internal cooling fanprevents internal accumulation of dirt. SP 4.900 main board has conformal coating layers to prevent harm caused by internal condensation, a condition that can happen when warm, moist air meets the amp chassis of a lower temperature.

SP 4.900 features a built-in sealed power cord, line inputs and speaker outputs for a bulletproof motorcycle application providing safe power delivery in even the worse weather conditions. The solid power supply harness ensures ultra-stable power and ground connection, preventing any loss of contact caused by vibration. Due to his specialized design, SP 4.900 is the ultimate option for Motorcycle, Marine, and Powersports applications.

SP 4.900 features built-in USS (Universal Speakers Simulator), a dynamic load circuit on Hi-Level inputs which initially shows the OEM output channel a load low enough to neutralize OEM speaker outputs muting protection circuit. Once the circuit activates, a higher load is introduced – still low enough to damp Class D outputs, but not low enough to cause current issues or heat dissipation problems.

SP 4.900 offers both remote-in signal detection and DC offset sensing on the speaker inputs for automatic turn on, providing total integration with any vehicle.

The versatile crossover filters and control knob are all located on a single side, to allow an easy calibration when the product is installed.

The filters section includes extremely flexible high-pass and low-pass crossovers, adjustable from 50 Hz to 5 kHz with 12 dB/Oct slope. Together with a bass-boost control (45 Hz, 0÷8 dB), they allow both front channels to be configured for full-range operation, or for use with a subwoofer and related speakers.

The high-pass crossover can also be used to optimize the performance of SPL Show NEO high-efficiency coaxial speakers, the perfect partners for SP 4.900.

General Specs
Channels 4 – 3 – 2
Nominal power supply voltage 11 ÷ 15 VDC
Pulse Operating voltage 6 ÷ 16 VDC
Idling current 1.1 A
Idling current when off 0.03 mA
Consumption @ 14.4 VDC, MIN load impedance (Max Musical Power) 50 A
Remote IN 6 ÷ 15 VDC (9 mA)
DC-REM – Remote Turn on by SPK DC from OUTPUT BTL speakers 3.5 ÷ 7 VDC
Distortion – THD @ 1 kHz, 4Ω, 70% Rated Power 0.02%
Damping factor @ 1 kHz, 4Ω, 2 VRMS 200
Bandwidth @ -3 dB 10 Hz ÷35 kHz
S/N ratio (A weighted @ 1 V Input) 105 dBA
Pre-In sensitivity 0.6 ÷ 6 VRMS
Speaker-In sensitivity 2.2 ÷ 22 VRMS
Minimum load impedance:
@ 4Ch
@ 3Ch 2Ω + 2Ω + 4Ω
@ 2Ch
IP Rating IP55
Operating Temperature Range 0°C (32°F) to 55°C (131°F)
Max size (mm/inch) 211.6 x 130 x 49 / 8.33 x 5.118 x 1.929
Weight (kg/lbs) 2.15 / 4.74
Adjustable Crossovers yes
INPUTS: Pre IN / Speaker IN
Ch 1-2
Hi-pass 50 ÷ 5k Hz @ 12 dB/Oct.
Lo-pass: 50 ÷ 5k Hz @ 12 dB/Oct.
Ch 3-4
Hi-pass 50 ÷ 5k Hz @ 12 dB/Oct.
Lo-pass 50 ÷ 5k Hz @ 12 dB/Oct.
Bass Boost 45Hz (adjustable) (0 ÷ 8) dB [LP = ON only]
Physical Specs

SP 4.900

mm in
A 205 8.07
B 211.6 8.33
C 107 4.212
D 130 5.118
E 49 1.929

Vehicle Information

• 1998-2013 Harley-Davidson Road Glide

Additional information

Weight 3.88 lbs
Dimensions 12.00 × 12.00 × 12.00 in