Hertz SPL Show SP 4.500 Class-D 4-Channel Amplifier, 90W x4 @4Ω / 150W x4 @2Ω RMS

Hertz SP 4.500 is a compact Class-D 4-channel amplifier from the SPL Show series, built for high-efficiency installs where space, durability, and clean output matter. It’s designed to run front/rear speakers from a single chassis, with flexible 4CH/3CH/2CH operating modes.

In 4-channel mode, the SP 4.500 delivers 90W RMS x4 @4Ω or 150W RMS x4 @2Ω (14.4V, 1% THD). It also supports 3-channel and 2-channel bridged configurations using manufacturer-published power ratings, making it a practical “one amp” solution when wiring and space are tight.

Key Performance Features

• Class-D (ADC Advanced D-Class) output stage with up to 87% efficiency
• IP55-rated aluminum chassis for protection against humidity and external agents
• Balanced fully-differential high-noise rejection inputs
• USS (Universal Speakers Simulators) speaker-load detection for OEM head unit compatibility
• ART (Automatic Remote Turn-On/Off) (enable/disable) for OEM integration
• Sealed power/inputs/speaker outputs to help prevent oxidation
• Single-side access to filter controls for easier in-vehicle calibration

Power Output (RMS)

• 4CH @4Ω: 90W x 4
• 4CH @2Ω: 150W x 4
• 3CH: 80W x 2 @4Ω + 330W x 1 @4Ω
• 3CH: 145W x 2 @2Ω + 300W x 1 @4Ω
• 2CH bridged: 300W x 2 @4Ω

Input / Output & Tuning

• Inputs: Pre IN / Speaker IN
• Input sensitivity: 0.2–6V RMS (Pre IN), 2.2–22V RMS (Speaker IN)
• Filter (OUT 1–2): Hi-pass 50–5k Hz @ 12 dB/oct, or Full
• Filter (OUT 3–4): Hi-pass 50–5k Hz @ 12 dB/oct; Lo-pass 50–500 Hz @ 12 dB/oct; or Full
• Bass Boost: 45 Hz, adjustable 0–8 dB (LP = ON only)

Installation Use Cases

• Front + rear speaker amplification in compact builds
• 4-channel amp for OEM integration where turn-on and load detection matter
• 3-channel setup (front speakers + bridged sub channel) using published 3CH ratings
• Space-constrained installs needing sealed connectors and an IP-rated chassis

Technical Specifications

• Brand: Hertz
• Series: SPL Show
• Model: SP 4.500
• UPC: 8018823139922
• Amplifier Class: Class D (ADC Advanced D-Class)
• Channels: 4
• Frequency Response (-3 dB): 10 Hz – 35 kHz
• S/N Ratio (A-wtd @ 1V input): 100 dBA
• Distortion (THD @ 1 kHz, 4Ω, 70% rated power): <0.02%
• Damping Factor (@ 1 kHz, 4Ω, 2V RMS): >150
• IP Rating: IP55
• Max Size (mm/in): 192.7 x 130 x 49 mm (7.59 x 5.12 x 1.93 in)
• Weight: 1.9 kg (4.18 lb)

What’s Included

• (1) Hertz SP 4.500 amplifier
• (1) Power supply harness
• (1) Speakers-out harness
• (4) Installation screws (3.5 x 25 mm)
• (4) Wire-to-RCA adapters

Why Buy From MCOR Automotive

• Authorized retailer
• Expert amplifier matching and system design support
• Fast fulfillment with knowledgeable install-level guidance

Physical Specs

	mm	in
A	185.7	7.31
B	192.7	7.58
C	107	4.21
D	130	5.12
E	49	1.93

Fitment, Installation & Warranty Notes

• Fitment Help: Need help confirming fitment, compatibility, amplifier matching, or installation parts? Use our Fit Guide or contact us through the chat button before ordering.
• Authorized Retailer: MCOR Automotive is an authorized Hertz retailer. Products purchased from MCOR include applicable manufacturer warranty coverage when installed and used according to manufacturer guidelines.