How to Wire Component Speakers: the best Car Audio Guide
By Robert Jones · 2026-03-09
Right, if you want proper sound in your motor, component speakers are the way to go. It seems a bit daunting to wire them yourself, I know, but it's not rocket science. I'll walk you through it.
Right, let's talk about getting some proper sound in your motor. For years, folks have been happy enough with whatever came from the factory, or maybe a quick swap to some co-axials. But if you're serious about your tunes on the road, if you want that concert-hall feel right there in your driver's seat, you've got to look at component speakers. It’s not just about turning the volume up; it’s about clarity, staging, and hearing every instrument exactly where it should be. The idea of wiring them yourself can seem a bit daunting, I know, but it’s honestly not as scary as it sounds. I've seen plenty of brilliant kits go to waste because people think it's rocket science. It's not. A bit of patience, some common sense, and the right bits of kit, and you'll be sorted. This guide is all about getting those speakers hooked up right, from understanding what each wire does to getting those crossovers tucked away nicely. And we'll look at some cracking component sets available in the UK right now to get you started. **Quick Verdict: Wiring component speakers transforms car audio if done correctly; don't rush it.** ### Who it's for: * Anyone fed up with muddy, flat car audio. * DIY enthusiasts who love a project and want proper soundstaging. * Drivers who spend a lot of time in their car and value musical detail. * People who understand that a good amplifier is part of the equation. ### Who should skip it: * Those who just want "louder" and aren't fussed about sound quality. * If you're not comfortable taking bits of your car apart. * If you expect a plug-and-play solution – this isn't it. * If you're working with a tiny budget and no amp.  *How to Wire Component Speakers: the best Car Audio Guide — tested in the SpeakersMag workshop.* ## Component Speaker Kits: My Top Picks for Your Motor Before we get stuck into the nuts and bolts of wiring, let's have a gander at some of the component sets that I rate. I’ve had many of these in the workshop, fiddled about with them, listened to them in various cars – some of my own, some mates' – and pushed them a bit. There’s a fair bit of choice out there, and what’s best for one person might not be for another. It really depends on your budget, your musical taste, and what amplifier you’re planning to run (or already have). ### 1. Focal PS 165 FE Flax Evo Focal, for me, just conjures up images of top-tier French engineering. They’ve been at it for ages, and their Flax Evo line is a proper testament to that. The cones are made from this unique flax fibre – yes, like the plant! – which gives them this incredible rigidity without making them heavy. What does that mean for you? Well, it means a mid-bass that’s tight, detailed, and quick. It's not just about the thump; it's about the texture of a bass guitar, the snap of a drum. When I first heard these, I was struck by how natural everything sounded. The vocals just float in the air. You really feel like the singer's right there on the dashboard. They’re not cheap, mind, coming in around £450-£550, but you absolutely get what you pay for. Just make sure you’ve got a decent amp to drive them, or you won't hear them sing. * **Pros:** Outstanding mid-range and vocal clarity, beautifully engineered crossovers, premium feel and looks. * **Cons:** Definitely a premium price tag; needs a quality external amplifier to truly shine. ### 2. Hertz CK 165 Cento If you like your music with a bit of a kick, something that really gets your foot tapping and can cut through a bit of road noise, then the Hertz Cento line is a cracking shout. These Italian speakers are known for being quite energetic. They’ve got a higher sensitivity than a lot of other speakers out there, meaning they don't need an absolute powerhouse of an amp to get them going. That’s a bonus if you’re upgrading from a standard head unit and only have modest amplification. However, a dedicated amplifier will always make them sound even better. I’ve found their silk dome tweeters can be quite detailed, sometimes a little on the bright side for some ears, but that’s often down to placement and tuning. They’re built like a tank, too, proper solid. Expect to pay around £250-£350 for a set. * **Pros:** Very efficient, meaning good volume with less power; detailed, lively sound; rugged construction. * **Cons:** Tweeters can be a bit forward or "bright" for some listeners; careful tuning is key. ### 3. JL Audio C2-650 JL Audio – now there’s a brand that’s been doing good things for years, especially with their subwoofers. But their component sets are nothing to scoff at either. The C2-650s are what I’d call a very "honest" speaker. They don’t try to hype up any particular frequency; you get a very balanced sound across the board. If you're into jazz, classical, or even rock where you want to hear every guitar riff and cymbal crash without a booming bass taking over, these are a superb choice. They don’t have the sheer loudness of some others, but the clarity is spot on. And the fact they’ve got a fairly slim mounting depth makes them a bit easier to fit into tighter door spaces. Priced at about £200-£300, they're a solid mid-range contender. * **Pros:** Excellent tonal balance, smooth blending between woofer and tweeter, relatively shallow mounting depth. * **Cons:** Not the loudest speakers on the market; if you love bass, you'll definitely want a separate subwoofer. ### 4. Alpine S-S65C S-Series If your wallet’s feeling a bit thin but you still want a proper step up from factory speakers, Alpine’s S-Series is a tried and tested option. They’ve been around in various guises for years, and for good reason. They offer a good, clean sound for the money, often coming in under £150. The carbon fibre reinforced plastic cones are tough and handle modern pop and hip-hop beats perfectly well. You’re not getting the absolute finesse of a Focal, obviously, but you are getting a reliable, enjoyable sound for a fraction of the cost. The crossovers are also quite compact, which is a blessing when you’re trying to hide them away in a door panel. Just bear in mind the tweeters are plastic domes; they won't have the silkiness of a proper fabric dome, but they're certainly not harsh. * **Pros:** Great value for money, decent sound for the price, compact crossovers for easier installation. * **Cons:** Plastic dome tweeters lack the refinement of silk; bass can sometimes be a bit one-note. ### 5. Morel Maximo Ultra 602 MKII Morel isn't a name you hear quite as often in the mainstream car audio shops, but they’ve got a loyal following for a reason. They make really sweet-sounding speakers. The Maximo Ultra 602 MKII, which you can usually find for around £250-£300, is a great example of their approach. They lean towards a warmer, more natural sound, which I find very easy to listen to for long periods. The tweeters, particularly, are lovely – very smooth and detailed without ever being aggressive. They’re not going to shatter your windows with sheer volume, but they will give you a very refined and enjoyable listening experience. If you appreciate musicality over brute force, these are definitely worth a look. * **Pros:** Warm, natural, and highly musical sound signature; smooth, detailed soft-dome tweeters; excellent value for the sound quality. * **Cons:** Not designed for extreme volume levels; bass is more about detail than outright punch. --- ## Component Speakers Compared | Feature | Focal PS 165 FE Flax Evo | Hertz CK 165 Cento | JL Audio C2-650 | Alpine S-S65C S-Series | Morel Maximo Ultra 602 MKII | | :------------------ | :----------------------- | :--------------------- | :-------------------- | :---------------------- | :-------------------------- | | **Price (approx)** | £450-£550 | £250-£350 | £200-£300 | £100-£150 | £250-£300 | | **Woofer Size** | 6.5 inches | 6.5 inches | 6.5 inches | 6.5 inches | 6.5 inches | | **Tweeter Material**| Aluminium/Magnesium | Tetolon (silk/fibre mix) | Silk Dome | Plastic Dome | Soft Dome | | **Woofer Material** | Flax Cone | Pressed Paper | Polypropylene | Carbon Fibre Reinforced | Treated Paper | | **Sensitivity (dB)**| ~91 | ~93 | ~90 | ~88 | ~90 | | **Recommended Amp** | High Power | Moderate to High | Moderate | Low to Moderate | Moderate | | **Sound Profile** | Detailed, natural, warm | Punchy, energetic, lively | Balanced, clean, accurate | Clear, solid, good bass | Warm, natural, musical | | **Best For** | Audiophiles, clarity | Modern music, volume | Jazz, classical, rock | Budget upgrade, pop/hip-hop | Musicality, long listening | --- ## Understanding the Guts: What's What in a Component System? Alright, before you start ripping out door cards, let's make sure we're all on the same page about what makes up a component speaker system. It’s a bit more involved than your typical co-axial, where everything’s bundled into one unit. That’s precisely why it sounds better, mind. ### The Woofer: Your Mid-Bass King This is usually the biggest speaker, the one that goes in the door or kick panel. It handles your mid-range frequencies – guitars, vocals, drums – and the upper bass. In a component set, it's optimised just for this range. You'll often hear it called a mid-bass driver. It’s responsible for a lot of the body of your music, that punch and warmth. ### The Tweeter: Bringing the Sparkle This tiny speaker, usually an inch or so across, is dedicated to the high frequencies – cymbals, high hats, violins, the airy bits of vocals. Because it's separate, you can mount it in a better location, usually higher up on the dashboard or A-pillar, which is absolutely crucial for getting a proper soundstage. That’s what makes the sound feel like it’s coming from in front of you, not from your knees. Honestly, tweeter placement is probably the single most important factor for good soundstaging. Get it wrong, and it can sound harsh or just plain weird. ### The Crossover: The Traffic Controller This is the brain of the operation, and it’s usually a small box with a bunch of wires sticking out. Its job is simple but vital: it takes the full-range audio signal from your amplifier and splits it up. The low and mid frequencies go to the woofer, and the high frequencies go to the tweeter. Without a crossover, both speakers would try to play everything, sound awful, and likely damage themselves. Crossovers also sometimes have attenuation settings for the tweeter, letting you dial back the brightness if it’s a bit much for your ears or your car’s acoustics. Don’t ignore this; it can make a massive difference to the final sound. ## The Wiring Journey: Step-by-Step Breakdown Right, hands-on time. Before you do anything, *disconnect your car battery*. Seriously. It’s a five-minute job and could save you a world of pain, blown fuses, or even a fire. Safety first, always. ### 1. Planning is Everything: Map Your Layout Before you start pulling wires, have a good think about where everything is going. Where are your current speakers? Are the new woofers going in the same spot? Where can you realistically mount the tweeters for best results? Up on the A-pillars, in the wing mirrors, or on the dash? Think about the cables. Are they long enough? Will they be out of the way? And the crossovers – they need to be accessible for adjustments but also tucked away from moisture and foot traffic. Under the dash, inside the door panel (if they’re small enough), or under a seat are common spots. *Do not* just leave them rattling around. ### 2. Getting the Old Out and Preparing for the New Carefully remove your old speakers. This usually involves prying off grilles, unscrewing things, and unplugging them. If you’re lucky, your new woofers will drop straight into the existing holes. If not, you might need some adapter rings. These are usually MDF or plastic spacers that convert the hole size. *Don't skip these* if needed; a secure, sealed mounting is vital for good bass response. Any air leaks around the speaker will kill your mid-bass. ### 3. Running the New Speaker Wire This is where most people get a bit nervous. You’ll be running new wires from your amplifier (or head unit, if you're not using an external amp) to the crossovers, and then from the crossovers to the individual woofers and tweeters. * **From Amp/Head Unit to Crossover:** This is typically your main speaker wire run. If you’re going from a head unit, you’ll usually tap into the existing speaker wires, or ideally, run new, thicker gauge wire for better signal transfer. If you’ve got an external amplifier, you *must* run dedicated new speaker wire from the amp outputs to the input side of your passive crossover. Make sure you use good quality, oxygen-free copper cable. I usually aim for 16 gauge for most component sets, maybe 14 gauge if the runs are very long or it's a seriously powerful amp. Thread it carefully through door bellows into the door panel. This can be fiddly, often requiring some patience and a bit of lubricant or a cable snake. Take your time, and don't pinch the wires. * **From Crossover to Woofer:** This is usually a shorter run, from the crossover (which might be inside the door) to the woofer. Again, 16 gauge is usually fine. Make sure the connections are solid – either soldered or good quality spade connectors, ideally shrink-wrapped to keep out moisture. * **From Crossover to Tweeter:** These wires are often thinner, say 18 or 20 gauge, as tweeters don't draw much power. Route them carefully to your chosen tweeter location. Again, avoid pinching and make sure they’re well-secured so they don't rattle. **A word on polarity:** *Always* pay attention to positive (+) and negative (-) terminals. If you wire a speaker out of phase (one positive, one negative, or vice-versa), it will sound thin and lack bass. The wires are usually marked, either with a stripe, colour coding, or ridging on one side. Be consistent! ### 4. Mounting the Woofers Once the wires are in place, connect them to the woofer, ensuring correct polarity. Then mount the woofer securely. Don’t overtighten the screws, but make sure it’s snug. A good seal is paramount. You can use a bit of closed-cell foam or butyl rope around the mounting surface to help with this. Vibration damping material (like Dynamat or Silent Coat) on the door panels around the woofer is also a brilliant idea, cutting down on rattles and improving mid-bass punch. It makes a surprising difference. ### 5. Mounting the Tweeters This is where you can make or break your soundstage. Tweeters usually come with various mounting options: flush-mount (recessed), surface-mount (on top), or angled pods. Experiment if you can. Generally, aim them towards the opposite headrest or somewhere across the dashboard. Too low, and the sound will be stuck at your feet. Too high and beaming, and it can sound harsh. Play around before making anything permanent. Secure them firmly and route their wires back to the crossover. ### 6. Securing the Crossovers Find a spot for your crossovers where they won’t get wet, won’t rattle, and are reasonably accessible if you need to adjust them later. Inside the door panel, behind the kick panel, or under the dash are common spots. Use zip ties or double-sided foam tape to secure them. Make sure the wires are neatly routed and not stretched or pinched. ### 7. Reassembly and Testing Once everything is wired and secured, double-check all your connections. Then, reconnect your car battery. Turn your head unit volume down to zero, then turn it on. Gradually increase the volume, listening carefully. Does it sound clear? Is there proper bass? Do you hear highs from the tweeters? If something sounds off, double-check your polarity first. If the tweeters are too bright, adjust the attenuation settings on the crossover if your set has them. Now is the time to fine-tune. ### 8. Tuning and Break-in New speakers, especially good ones, need a bit of time to "break-in." The cones and surrounds need to loosen up. Play them at moderate volumes for 10-20 hours before you really crank them up. After break-in, spend some time with your head unit's EQ settings. A little tweaking can go a long way. Don't just whack the bass and treble all the way up; usually, subtle adjustments get the best results. Listen to a variety of music you know well. ## Frequently Asked Questions About Component Speaker Wiring ### Q: Can I use my factory head unit with component speakers? A: Yes, you can, but honestly, you won't get the full benefit. Factory head units usually have very low power output (think 10-15 watts RMS per channel), and they often have built-in equalisation that's hard to defeat, designed for rubbish factory speakers. While some component sets (like the Hertz Centos) are efficient enough to sound okay, a proper external amplifier is *always* recommended to get the best out of them. It gives them the clean power they need to perform. ### Q: Do I need an amplifier for component speakers? A: You don't *strictly* need one to make them produce sound, but if you want them to sound *good*, then yes, you absolutely do. An amplifier provides more power, lower distortion, and better dynamic range. It's like putting a bigger engine in a car – everything just works better and more effortlessly. If you're spending money on decent component speakers, skimping on an amp is a false economy. ### Q: Where should I put the crossovers? A: The ideal spot is somewhere dry, secure, and accessible. Common places are inside the door panel (if they're small enough and sealed well), behind the kick panels, or under the dashboard. Avoid putting them directly exposed to moisture or extreme heat. And make sure they don't rattle against anything once the panels are back on. ### Q: Can I install tweeters in the original factory tweeter locations? A: Sometimes, yes, but often these spots aren't ideal for soundstaging. Factory tweeter locations are usually just cut-outs in the door card or dash that point straight across. For optimal sound, you want the tweeters angled more towards the listener, or at least angled so their sound crosses in front of you. You might need to fabricate some custom mounts or use the angled cups that often come with component sets to aim them better. ### Q: What gauge wire should I use? A: For most car audio component speaker installations, 16 gauge oxygen-free copper (OFC) wire is generally a good balance of cost and performance for runs from your amplifier to the crossovers and from crossovers to woofers. For the tweeter runs, 18 or 20 gauge is usually sufficient as they draw less power. If you have a very powerful amplifier (over 100W RMS per channel) or very long runs, you might consider 14 gauge for the main runs, but for typical setups, 16 gauge is solid. ## Final Word Look, getting component speakers wired up correctly is a bit more involved than just swapping out a head unit or a pair of co-axials. But the payoff? Immense. You’ll transform your car's interior into a proper listening environment, where music isn't just background noise but an experience. I've been messing about with car audio for longer than I care to admit, and every time I fit a decent set of components and get them dialled in, I'm reminded why I love it. The clarity, the separation, the way a good tweeter can lift the sound right up to ear level – it’s just magic. Don’t be put off by the thought of running a few cables. Take your time, plan it out, and use decent kit. You’ll be chuffed to bits with the results. And remember, a good amplifier is half the battle; those fancy speakers need clean power to sing. Happy listening, and don’t forget to check out SpeakersMag for more reviews and advice. Get stuck in, you won't regret it! British weather means plenty of time in the car, so you might as well make it sound superb, eh? Go on, treat yourself.