Too much power for subwoofer install?
 

I used to have two 12" subs installed in my RAV4. I built a custom box myself, 4 cubic feet and ported with tuning frequency at 33hz. I was running the subs at about 1200w RMS combined. I wanted to install some subs in my FR-S and I was going to transfer the amplifier in my RAV4 to my FRS. It does 600w @ 4 ohms, 1200w @ 2 ohms, and 1600w @ 1 ohm.

Before I get into choosing a sub and designing a box for it, I'd like to know if anything above 600w RMS is too much for a car this small? I was looking at a 10" Alpine type R, handles 1000w RMS @ 2 ohms so I'd have no problems providing power to it but I don't know if it would be overkill. would a single 10" around 600w RMS be a better choice? What do you guys think?

OEM audio is 100 RMS @ 2ohm for reference and is pretty clean

Nothing says you have to run it flat out, and you'll have plenty of headroom.

I had a 10" Type R in my Yaris sedan. It was a 1042d, so much lower RMS. Powered with an Alpine M450, iirc. The sub box was a sealed box, and this configuration was plenty for the Yaris.

I say go for the Type R, you can always keep the amp gain down, and use a sealed box for a more crisp bass response. And just turn up the gain when your is a bass heavy mood.

First, off, there is no real thing as too much power if you already own the amp.

The other thing is, no matter the size of the car, the more cone area/linear excursion a subwoofer has, the lower distortion it will be.

Technically, yes, I can "limit" the power from the amplifier by using a higher impedance subwoofer. My amp can deliver 1200w @ 2 ohm, but only 600w @ 4 ohms. That's why I asked the question; I don't know if I should use all the power my amp has to offer. Most subwoofers I'm looking at can be wired for 4 ohms or 2 ohms.

So I take it I should get a subwoofer that has a relatively high xmax? Regarding cone area, I'm probably going to stick with 10", maybe a 12" if I can design a ported box with the right volume that will fit in the trunk of the FRS.

Less power at more distortion... That's a little wierd

If you don't have enough power to get as loud as you want, then you'll end up clipping the amplifier, which increases distortion exponentially. So, if he already has the amplifier, it does no harm to use it, as it can be gained down as he noted, and this will prevent any possibility of clipping.


To the op, as far as xmax goes, that's a tricky thing. The only car audio manufacturers I trust xmax specs from are jbl, jl audio, and alpine. They generally post linear xmax, which is the maximum cone excursion before a certain distortion threshold is reached (20% for subwoofers, 10% for all other sizes). Just about all other manufacturers list xmax as some variation of the measurements of the voicecoil, which doesn't guarantee that it will have that much excursion while keeping distortion down. That said, the type r you are looking at is a very good subwoofer. Also keep in mind ported enclosures lower distortion on the low end, as they limit cone movement near the tuning frequency.

On using all of the power, the difference between 600 and 1200 watts is only 3db. The difference between 2 different subwoofers could easily erase that difference, and the difference between ported and sealed definitely would. I would find the subwoofer you want, and then decided whether to go 2 or 4 ohms.

I've got two 2 Alpine 12s in a relatively small sealed enclosure. Hits nice and, yes, it was too much power. I wound up wiring them in series to bring the impedance up.

Regardless, it's all about the box and how much space you want. You can get great sound with a single 10 in this car. You can get better sound with a dual ported 12 but you'll have no trunk!

Make sure you budget in sound deadening - this car rattles like hell with bass.

Yes it does

You could always turn the gain down instead of wiring up to larger impedances. That way if you decide you want a bit more boom you could turn the pot instead of cracking open the box and rewiring. Also, most dedicated sub amps have a bass knob these days anyway, right?

They only problem you'll face is space, and every panel is going to rattle.
My current set up is MTX amp 300w @4ohms on a single Xtant 10" sealed .75 enclosure. That's enough to rattle the mirror, and any lose panels.
My amp comes with an adjustable gain control knob. So far my gain is set at 50% and I usually have my gain control knob at 25% most of the time.

Pretty much I say 300 watts on this car is more than enough. But go for it. You may just endup going with a single sub.

Shoot, a simple 50w Bazooka tube is enough to cause things to rattle in mine. lol