Questions about Choosing the Right Subwoofer for My Car… Need Help!

Hey everyone, I’ve got some questions about getting a subwoofer for my car and I keep finding different opinions…

So I recently got a new car with a big trunk, and it’s already wired for a sub, so I’m ready to add one! My other car has a 10-inch sealed Kicker box with a 300-watt amp (I think?), and I like it, but it doesn’t hit those super low bass notes.

I’ve been looking for a used 15-inch sub, but they’re kind of hard to find, and most of the ones I see are cheaper brands like Power Acoustik and Dual. I’d really like something like Rockford or Kicker.

I’m not trying to go for the loudest bass (my job is loud enough and I don’t want my ears ringing). I just want something that handles those low notes well.

So my questions are:

  1. Does a higher wattage mean it’ll sound better, or is it just about volume? Like, would a 500-watt 15” work for what I want?
  2. Am I even looking in the right direction? Would a 12” sub be enough for those low notes?

Thanks in advance for any advice!

If you want to get those low notes, a ported box would really help. You could either buy one pre-made or try designing and building your own.

Frances said:
If you want to get those low notes, a ported box would really help. You could either buy one pre-made or try designing and building your own.

I’m thinking a custom ported box would be great (I have access to a CNC router), but for now, if I buy a sub used or new, I’d probably go for a pre-built box and then later make a custom one to fit my trunk better.

@Sage
Yeah, that makes sense. By the way, even a 12” in a well-made, well-tuned ported box can give you those low notes you’re after.

Honestly, it all comes down to personal preference. I use a single 15 on 8k and a single 12 on a 5k. Personally, I wouldn’t be happy with a 500-watt setup, but most people would probably like it.

More wattage gives more potential, but it doesn’t always mean it’ll be louder. A well-made 500-watt setup with a sensitive sub can be louder than a poorly designed 2000-watt setup.

If you’re sticking with a budget, JL, Rockford, and Kicker are solid in the 500-watt range. Anything else is kind of a gamble in my experience.

@Lior
Yeah, I’ve been leaning toward Rockford or Kicker, but good to know that JL is solid too. I was looking on Amazon, and for about $300, I could get a Kicker 43C154-N (4 ohm, 300W RMS, 600W peak) in a sealed box, plus a Kicker 800.1 amp. Used subs are getting pricey, so I might just spend the extra and go new.

@Sage
Since you want those low notes, I’d suggest a ported setup tuned around 31-33Hz. Harmony Audio has some mid-range sub and box combos that might suit your needs if you want something affordable.

Why buy a pre-made box now if you plan to build one later? Maybe you could either find a good pre-made one that fits perfectly or go straight to building your own?

Frances said:
Why buy a pre-made box now if you plan to build one later? Maybe you could either find a good pre-made one that fits perfectly or go straight to building your own?

Mainly a time issue. I’ve got other projects going on, so I don’t have time to make a custom box now, but I want a sub setup soon. Later on, I’ll build a custom box to save space in my trunk.

I’m using a Stereo Integrity HT 18 in a custom sealed box with a Kicker CXA 800.1 amp. It really nails those low notes! Any Stereo Integrity sub, 12 inches or larger, will give you what you want.

About your wattage question… it depends on the sensitivity of the sub. Imagine the sub cone like a weight that needs more power to move if it’s heavy. But higher sensitivity doesn’t always mean better sound quality.

These days, amps with thousands of watts are affordable, so you can get a powerful setup without breaking the bank. You could use a high-power, low-sensitivity sub in a sealed box, and it’ll give you solid low-end sound without overheating.

If you’re looking at something like an infinite baffle setup, it doesn’t need as much force to hit those lows, so the sub’s design is different. That’s why subwoofer companies make different models for different box types.

@Harlow
Got it! So with, say, a 600-watt amp and a 500-watt sub… a low-resistance sub would generally stay cooler and use less power to get similar results compared to a high-resistance one?

Sorry, I’m still new to subs. I know about wiring and electronics from working with robots, but my audio knowledge is limited. I’m used to aiming for high impedance with headphones (I have 250-ohm ones) for better quality sound. But with a sub, I just want those low notes without shaking the whole car.

@Sage
No worries, I was in the same boat when I got started in car audio. Honestly, the wiring and electronics are only a small part of it. To really get good at this, you need to know about sound dynamics and speaker setups, not to mention building techniques.

As for resistance, I think you’re talking about impedance. The sub’s ohm rating isn’t the same as sensitivity. Amps supply a certain amount of voltage, and the ohm rating just shows how much current will flow for that voltage. Sensitivity is more about how well the sub turns electrical power into sound.

More power can make it louder, but only if the sub has the capability to handle it. Also, the acoustics of each car are different, so a sub that lacks upper bass in one car might sound better in another car with a different setup.