Best Four Channel Car Amplifiers

Which are the best four channel car amplifiers? These are the ones we like…

Up to this point, upgrading your car sounds is only about replacement of stuff and tuning it. You do not make any new holes in your car. But as we have said before, the addition of an amplifier is the Big Step. That’s because you need to make a hole between the engine bay and the cabin for a thick power wire. It must have a grommet to go through – a circular rubbery armour-ring. That wiring will be a significant instal cost-effort. You need to learn about the power you have available on your car’s electrical system.

There are three main forces at work with any car audio system design. Your car, your budget and your taste in music. These four channel amplifiers are about the upgrade with sanity. You want more and better and you want it in all four corners of your car. There may not be more than the one spend planned – this may be about that simple sound power increase. Nonetheless, choosing a four channel amplifier, one with more than just basic features, will be an investment in future upgrades. One or two here are able to get a bit flash later, if you do end up as an audiophile. These are the the best four channel car amplifiers, in our opinion.

They vary from value for money with grunt, to a slice of quality power, to the absolutely latest, newest thing. An amplifier that will fit into a modern stock system like never before. Even if your car has a stop-start system that would switch off normal aftermarket equipment.

Sony XMN1004 (£110)

The Sony’s MOSFET power supply transistor means better muscle. A more expensive device than standard ones, this used to be a feature of costly products. Now available on entry level stuff, it gives a good solid set of watts for the money. You only get a simple up or down or off choice of crossover, fixed at 80Hz per set of channels. That’s if you use them. You could just run all four corner speakers, louder. Or, feed a woofer from 80Hz downwards, (lowpass) bridged on one channel pair, with your main speakers on the other. These mains can have the deep bass below 80Hz kept from them (highpass) so they go louder before breaking up. Simple but effective at keeping the price down. A switch costs less than a potentiometer or knob.

The signal to noise ratio is the CEA compliant one, as Sony claim a 100dB one. The main thing is, it will be a good clean sound quality. A high value for money solution, even if Sony still use the peak rating in publicity saying you have 1,000W. The two panel mounted 25A fuses say 700W RMS, even if you have 14V of Direct Current in your system. Thus a deserved place in our group of the best four channel car amplifiers.

• Power Output: 4ohms 4 x 70W, 2ohms 4 x 85W, Bridged 4ohms 2 x 175W
• Current Draw/Fuse Rating: 2 x 25A
• Signal To Noise Ratio: 93dB
• Features Rich? Two switchable 80Hz highpass or 80Hz lowpass filters, one for each channel pair: Subsonic filter (no freq. stated); input 0.3V to 6V

JBL Club 704 (£200)

The design brief for the ‘Club’ car amps was about them fitting into smaller spaces. JBL mention the smaller footprint and lesser depth of chassis for the given wattage. JBL have been owned by the mighty Harman Industries folks for a long time and offer some clever OEM features. The main one is the RJ45 telephone style ADAS input socket. This overrides your audio when connected to an Advanced Driver Assistance System. You connect a T568B wire to the ADAS output. It will interrupt your tunes with any warning messages. You even get to pick which of the four corners you want the announcements to emanate from, with a knob. The Harman HALOsonic® systems of some vehicles can work with CLUB amps as well. It is a form of complex sound cancelling, like with headphones. There is an adjustable level control on the Club 704 just for that. This puts in in our group of the the best four channel car amplifiers.

The amp comes with four bare-wire to RCA adapters included to connect speaker wires to the RCA sockets directly. There is a pair of dedicated RCA pre outs. No subsonic filter though. The adaptors mean the amp  doesn’t need a separate high level socket-and-loom but the adaptors must be more costly. It’s about a robust input stage that can just take signals from 0.2V to a whopping 20V speaker level. They use a three-level power switch to pick ‘Lo’ or Hi1 or Hi2’ to do it.

• Power Output: 4ohms 4 x 70W, 2ohms 4 x 100W, Bridged 4ohms 2 x 200W
• Current Draw/Fuse Rating: 2 x 30A
• Signal To Noise Ratio: 85dB
• Features Rich? Two switchable 32Hz to 320Hz highpass/lowpass filters, one for each channel pair: Speaker level or RCA input: RCA line output: ADAS connectivity and HALOsonic® noise cancelling where compatible

KICKER CXA360.4 (£220)

Uniquely, this Class A/B amp comes with vertical mounting hardware as an option. It has a red circuit-protection LED to tell you if there’s anything wrong as well as the green power LED. There’s a 3.5mm socket for an optional CXARC remote bass knob and a pair of push buttons on the panel. One is about low level (0.125V to 5V) or high level (0.25V to 10V) signals, the other is marked ‘fader’. The first is about RCA wires or else speaker-to-RCA convertor wires being used to feed at speaker level. The fader one means leave it in the ‘Off’ position and you can use all four channels on one feed.

Kicker’s very name is about visceral bass, so it is no surprise to learn they have a special 40Hz bass boost. Not just a stated Q factor of say 0.5, which is about the breadth of frequencies lifted. Rather, it is their own little humpy curve, actually registered, like the PunchEQ is by Rockford Fosgate. Called KickEQ™, you get a dedicated adjuster per channel pair to take it up to as much as +6db. This is power hungry as its based 5Hz below most boost circuits’ choice-point. Deeper and humpier! So you use it with care and ideally, add that plug-in remote bass control on a wire. It is one of the the best four channel car amplifiers,due to these features, with the power.

A well thought out piece of kit. Kicker’s CXA360.4 makes efforts to be as widely compatible with different power levels of input as possible.

• Power Output: 4ohms 4 x 65W, 2ohms 4 x 90W, Bridged 4ohms 2 x 180W
• Current Draw/Fuse Rating: 40A
• Signal To Noise Ratio: 95dB
• Features Rich? Two switchable highpass/lowpass filters for 50Hz to 200Hz and KickEQ™ 40Hz Bass boost adjustable 0 to +6dB: Hi/Low level switch for RCA input: Remote bass control jack socket

Alpine S-A32F (£250)

Alpine have always had an escalating series of products, from affordable but still good to state of the art. The top end products get the new technology while the lesser ones get the clever stuff later. This is called filtering-down of technology and is the highest value for money way to buy in. What starts in F1, ends up in posh cars, then cheaper ones. ABS braking is a good example. The S-Series amps feature technology that was once only in the higher R and X-series. S-Series amps offer three models. A four channel, a five channel and a mono model, so no two channel. A Class D amp, with many years of Alpine development behind it.

This means the S-A32F is a keen price for the always-lovely Alpine looks and has some cool features. There’s an optional RUX-KNOB2 bass control you can plug in for channels 3 and 4 when bridged into a woofer. There’s a high/low input level switch for the four RCA sockets. High is from 0.5V to 10V for speaker level. You’ll need to get some RCA connectors with open cable leads to add the speaker wires for that application. The low level input for normal RCA feeds is from 0.2V to 4V. Signal to Noise Ratio is excellent at 98dB and means that this is another top value sound quality tip. You are best to pair this with Alpine S-Series speakers. They are available as 6×9 ovals, coaxials in 6.5in, 5.25in and 4in as well as 6.5in components.

Looks good, sounds good. Because #Alpine!

• Power Output: 4ohms 4 x 55W, 2ohms 4 x 80W, Bridged 4ohms 2 x 160W
• Current Draw/Fuse Rating: 40A
• Signal To Noise Ratio:98dB
• Features Rich? Two switchable highpass/lowpass filters for 50Hz to 400Hz, one per pair of channels:  Speaker level input with auto power-on (adapters) or RCA input: CH3/4 level control socket

Audison SR4.300 (£350)

Another small footprint Class D amplifier with proprietary tech (company’s own smarts) in its guts. Each company’s take on the smaller Class D-with-quality amp seems to do this. Audison love an Acronym and call theirs ADT for Audison D-class Technology. It’s a dense little amp and has the fine controls hidden under a top panel, rather than on one end. The crossover point for each channel pair can be chosen between 50Hz and a very high 3.2kHz. That’s because the SR4.300 is also designed to work for running active component speakers. It’s when you have a pair of channels for the tweeters and feed them only highs. Another pair of channels runs the mid-bass drivers, on their own crossed-over set of watts – no highs, though. An accepted much higher end way to run a set of high quality components and is louder and clearer. You need a very serious class of component driver though and it’s closer to professional audio than home hifi.

Audison have their BIT- control system that can be used with this amp. When connected, it bypasses the whole control panel, allowing an unsurpassed choice of upgrade path possibilities for this amplifier. A lot like the Wāvtech, this too has some cunning when it comes to OEM integration. If you plug in via the speaker wires, the amp has what Audison call USS or Universal Speakers Simulator. This pretends to be the low impedance load often engineered into stock systems’ amplifier self-protection circuits. That’s so that if a stock speaker blows, you don’t want the OEM amplifier cooking in its hidden spot.

A serenely clever item that can do ‘high end’. Definitely one of the very best four channel car amplifiers.

• Power Output: 4ohms 4 x 85W, 2ohms 4 x 130W, Bridged 4ohms 2 x 250W
• Current Draw/Fuse Rating: 40A
• Signal To Noise Ratio: 100dBA
• Features Rich? Two switchable highpass/lowpass filters for 50Hz to 3.2kHz, one per pair of channels: Speaker level input sockets and RCA inputs: RCA line output: ART auto remote turn-on feature button

WĀVTECH link300.4mini (£400)

An installer’s dream, brand new in concept and for those who want results, without having anything on display. Best of all, it will make fab music from one tiny box, in brand new cars that stop and start. Made for OEM integration, the new Wāvtech range is designed by audio nutters who are true hardcore tech types. The low signal to noise ratio quote is because they use the tougher qualified version of the spec. A-weighted, it is about human hearing rather than a flat measurement. That will have done a savage flyby on any reader except deep audiophile experts and audiologists! This is their baby super compact Class D 4×50 watter. There is a bigger one and also two monoblocks. The link300.4mini needs a four gauge power wire, despite being such a small unit.

The amp accepts RCA signals from 0.2V to 5V on ‘low’ setting, or 0.4V to a whopping 10V on ‘high’. A deeply cool feature if you do have a mad-end front music unit. On speaker level, for taking OEM speaker wire feeds, it is quietly insane. For one, no matter the power of your car’s OEM set up, it will cope. It will also look like the stock system to the car’s amp’s impedance-sensing. This is about factory speakers made to run at funny low impedances to suck a few more factory-amp watts. It cons the car’s own amp into thinking it’s all normal. Best of all, you can take wires from your car’s tweeter and mid-bass driver’s wires and ‘sum’ them. It is a bit complex in concept but it means you get the best of everything.

A truly leading edge future-now product for modern cars and a newbie in the the best four channel car amplifiers’ world.

• Power Output: 4ohms 4 x 50W, 2ohms 4 x 75W, Bridged 4ohms 2 x 150W
• Current Draw/Fuse Rating: 40A external fuse required
• Signal To Noise Ratio: 80dBA (if measured ‘flat’, would be well over 100dB)
• Features Rich? Two switchable lowpass/highpass filters 50Hz to 500Hz: Summing speaker or RCA input: Auto turn-on by remote wire, DC offset or audio signal: OEM stop/start compatible, Input from 0.2V to 40V, five sets of protection circuitry and LED peak light