Zapco ST-104D SQ MINI Amp 4 Channel Class D Bridgeable Mini Car Amplifier
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The Zapco ST-104D SQ MINI is a micro-chassis 4-channel Class D bridgeable car amplifier rated at 4 x 95W RMS at 4 ohms and 4 x 120W RMS at 2 ohms. It is part of Zapco's SQ MINI range, designed for tight installs where a full-size amplifier will not fit.
The Zapco ST-104D SQ MINI is also available as the ST-104D SQ III, a compact (non-MINI) 4-channel Class D amplifier rated at 4 x 100W RMS.
Key specifications
- Model: ST-104D SQ MINI
- Channels: 4, full range, Class D
- Power @ 4 ohms: 4 x 95W RMS
- Power @ 2 ohms: 4 x 120W RMS
- Bridged @ 4 ohms: 2 x 240W RMS
- Inputs: RCA and speaker level; auto-on with speaker level
- Frequency response: 15Hz – 30kHz ±1dB
- Dimensions: 95 x 37 x 236 mm (W x H x L, overall)
ST-104D SQ MINI
4-Ch. Class D Mini Amplifier
A compact four-channel Class D amplifier built for installs where space is limited, without compromising sound quality. Accepts both RCA and speaker level inputs and is bridgeable for flexible installation options.
- Optional HD Bluetooth
- Variable input gain control
- Variable electronic crossover
- Auto-on with speaker level inputs
- Micro chassis
- Variable bass boost control
Explore the full range in Micro Amplifiers.
Specification
| Power @ 4Ω | 4 x 95 watts |
|---|---|
| Power @ 2Ω | 4 x 120 watts |
| Power Bridged @ 4Ω | 2 x 240W RMS |
| Frequency Response | 15Hz to 30KHz ±1dB |
| Net Dimensions (mm) | 95(W) x 37(H) x 214(L) |
| Overall Dimensions (mm) | 95(W) x 37(H) x 236(L) |
More specs
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What's Included
- Zapco ST-104D SQ MINI
Zapco
About the Zapco ST-104D SQ MINI
From our tech experts at CEN
The Zapco ST-104D SQ MINI is a micro-chassis 4-channel Class D bridgeable car amplifier, measuring 95 x 37 x 236mm overall. It delivers 4 x 95W RMS at 4 ohms, 4 x 120W RMS at 2 ohms, or 2 x 240W RMS bridged. Both RCA and speaker-level inputs are included, with auto-on from a speaker-level signal.
Who it suits
This amplifier suits anyone who needs genuine 4-channel power in a tight install — under a seat, behind a trim panel or in a shallow boot space. Drivers who have more room may prefer the full-size Zapco HB 104D II at a similar power rating.
Our tech experts advise
Speaker-level inputs make this compatible with factory head units without a line output converter. A built-in variable electronic crossover and bass boost give useful tuning flexibility without extra processors. Bluetooth audio streaming is an optional add-on. Fitting cost varies by vehicle; see our car audio installation page for details.
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.
- 1
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.
- 3
Fitted at our workshop
Bring it to our Beeston workshop and we do the rest.
Unit 25 Technology Drive, Beeston, Nottingham NG9 1LA
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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: Will an amplifier work with my factory head unit?
A: Yes, in most cases. If your head unit has no RCA outputs you will need a line output converter to feed the amplifier a clean signal. CEN stocks line output converters and can advise the right one for your vehicle.
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: Does the ST-104D SQ MINI have Bluetooth?
A: HD Bluetooth is optional on the ST-104D SQ MINI rather than built in.
Q: Will the ST-104D SQ MINI turn on with a factory head unit?
A: Yes. It has speaker level inputs with auto-on, so it can switch on from the speaker signal.
Q: How small is the ST-104D SQ MINI?
A: It measures 95mm wide, 37mm high and 214mm long (236mm overall).
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