Zapco HB 104D II Amp 4 Channel Class D Bridgeable Amplifier 4x100w RMS
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The Zapco HB 104D II is a compact 4-channel Class D bridgeable amplifier from the Zapco Harmony HB II series, delivering 4 x 100W RMS at 4 ohms with RCA and speaker level inputs.
This listing is the HB 104D II. The Harmony HB II series is also available as the Zapco HB 154D II delivering 4 x 150W RMS at 4 ohms.
Key specifications
- Channels: 4
- Class: D
- Power at 4 ohms: 4 x 100W RMS
- Power at 2 ohms: 4 x 150W RMS
- Bridged power at 4 ohms: 2 x 250W RMS
- THD at rated power: <0.5%
- THD + Noise: <0.1%
- Signal to noise ratio: >90dB
- Frequency response: 20Hz–20kHz ±1dB
- Input sensitivity: 0.25v–6v (Low)
- Inputs: RCA and speaker level
- Dimensions: 170 (L) x 115 (W) x 45.5 (H) mm
4-Ch. Class D Amplifier
Full-range 4-channel Class D amplifier with RCA and speaker level inputs, variable input gain control and variable electronic crossover. A compatible DSP remote is available with the Zapco HB DSP II-R.
- Power @ 4Ω: 4 x 100 watts RMS
- THD @ Rated Power < 0.5%THD
- Power @ 2Ω: 4 x 150 watts RMS
- Power Bridged @ 4Ω: 2 x 250W RMS
- Signal to Noise Ratio > 90dB
- THD + Noise < 0.1%
- Frequency Response 20Hz to 20KHz ±1dB
- Input Sensitivity .25v to 6v (Low)
- Dimensions (mm): 170 (L) x 115 (W) x 45.5 (H)
Explore the full range in Zapco Amplifiers.
Specification
| Channels | 4 |
|---|---|
| High Level Inputs | 4-Channels |
| RCA Inputs | 4-Channels |
| RMS Power (4 Ohm) | 4 x 100W |
| RMS Power (2 Ohm) | 4 x 150W |
| RMS Power (4 Ohm, Br.) | 2 x 250W |
| S/N Ratio | > 90dB |
| THD | < 0.1% |
| Frequency Response | 20Hz - 20KHz |
| Input Impedance | 22 KOhm |
| Input Sensitivity | 250mV - 6V |
| Gain Control | 6V - 0.25V |
| Crossover | HP/Full/LP |
| Crossover Frequency | 30Hz - 80Hz |
| Supply Voltage | 12V -14.4V |
| Unit Dimensions (mm) | 170(L) x 115(W) x 45.5(H) |
What's Included
- Zapco HB 104D II
Zapco
About the Zapco HB 104D II
From our tech experts at CEN
The Zapco HB 104D II is a compact 4-channel Class D bridgeable amplifier from the Harmony HB II series, measuring 170 x 115 x 45.5 mm. It delivers 4 x 100W RMS at 4 ohms, rising to 4 x 150W RMS at 2 ohms or 2 x 250W RMS bridged, with both RCA and speaker level inputs.
Who it suits
Well suited to anyone building a four-speaker car audio system who wants Class D efficiency in a tight installation space. Those needing more headroom can step up to the Zapco HB 154D II, which delivers 4 x 150W RMS at 4 ohms.
Our tech experts advise
Speaker level inputs mean this amplifier suits vehicles without a dedicated aftermarket head unit. A variable electronic crossover and input gain control are built in. Fitting is priced per vehicle — see our car audio installation page. The compatible Zapco HB DSP II-R adds remote DSP level adjustment.
Explore the full Zapco range at CEN, with fast UK dispatch and expert advice from our Nottingham team. Shop all Zapco
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Have it Fitted By Our Team
Our team fits car audio, stereos, dash cams and vehicle security at our workshop in Beeston, Nottingham. Tell us your vehicle and we'll confirm the parts and a fitted price.
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Tell us your vehicle
Make, model and year, and what you'd like fitted.
- 2
We confirm the parts
Fascia, wiring and interfaces checked for your car, with a fitted price.
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Bring it to our Beeston workshop and we do the rest.
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Frequently Asked Questions
Q: How do I choose the right amplifier for my speakers or subwoofer?
A: Match the amplifier's RMS output per channel to the RMS handling of your speakers or subwoofer at the same impedance. The Specification tab lists the power figures. If in doubt, contact CEN with your setup and we will recommend a match.
Q: What wiring do I need to install this amplifier?
A: You will need an amplifier wiring kit sized to the amplifier's power draw, typically including power and earth cable, a fuse, RCA leads and a remote wire. CEN stocks complete wiring kits, and the amplifier's fuse rating is the guide to the cable gauge required.
Q: What class of amplifier is this and does it matter?
A: Class D amplifiers are compact and efficient, ideal for subwoofers and modern installs. Class AB designs are traditionally favoured for outright sound quality on mid and high frequencies. The class is listed in the Specification tab where provided.
Q: Can CEN install this amplifier?
A: Yes. CEN offers professional amplifier installation from our Nottingham premises, including secure mounting, wiring and setup. Contact us to book.
Q: How much power does the Zapco HB 104D II produce?
A: It delivers 4 x 100 watts RMS at 4 ohms, 4 x 150 watts RMS at 2 ohms, or 2 x 250 watts RMS bridged at 4 ohms.
Q: Can the HB 104D II connect to a factory head unit?
A: Yes. It has speaker level inputs as well as RCA inputs, with variable input gain control.
Q: Can the HB 104D II run a subwoofer?
A: It is a full range amplifier with a variable electronic crossover, and it can be bridged to 2 x 250 watts RMS at 4 ohms.
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