[lowrydr310]

I'm looking to add a subwoofer in the trunk of my 330i. I know how to add it, there are dozens of posts about that, but my question is more about which type of enclosure to go with.

I did this on my 325i and it was one of the easiest subwoofer installations I've ever done. I used a Rockford Fosgate P300-12 subwoofer which is a sealed enclosure with an integrated 300W RMS class D mono amplifier. I used a standalone line output converter tapping off the HiFi amplifier output, instead of wiring directly to the amp despite the amplifier being able to accept speaker level inputs.

That was two years ago and I paid $150 for that brand new. Now that same subwoofer is $250, and despite still being an excellent value I found some other options for that same price that I'm considering.

I'm looking at a JL Audio 10" Basswedge which is a loaded ported enclosure. Unfortunately I have zero experience with ported subwoofers in car audio. I have only ever used single 12" sealed subwoofers in four different cars, and all have been so excellent I've had no need to try a different setup. Some of the reviews for this product specifically mention my biggest concern with a ported sub - that it's only very effective for the frequency that the port is tuned for, and that anything far off of that frequency sounds flat. Is there any truth to this?

Back in the day when I first got into this car audio game, there were numerous shops which had fancy displays where I could demo a bunch of gear before buying. Sadly those shops aren't around any more since the internet and Best Buy seem to have taken over.

[kaigoss69]

Buy it from a reputable vendor, with good return/upgrade policy. Easy to install and try out!

[E92x7z]

this 325i is a E46 model or E9x ?
have more active sub boxes ... but better is a custom made Sub + amp this low Hz need going to driver and cabin not sitting in Trunk

[Emilime75]

Ported/vented vs sealed-

The general consensus is that the sealed sounds "tighter" than vented, but this is only so if the box and vent aren't designed/built properly for the driver.

Vented, if designed right, will be more efficient at and above the tuning frequency of the vent, i.e. you'll get more output from a vented system than you would from a sealed system.

Vented is more difficult to design and build. Sealed is very forgiving, i.e. a sealed box doesn't have to be exactly the right size, so a bigger variety of drivers will sound OK in a given box. For vented, box size and vent tuning/dimensions are critical per the driver chosen if you want a flat response out of it-in this case, "flat" is good, it means there are no large peaks and dips in the response of the driver.

For maximum performance, your best bet would be to choose the driver that will do what you want, then design/build the right box for it, or have someone experienced with this do it for you. The premade offerings take a lot of shortcuts and make compromises in order to appeal to many while meeting a budget requirement. Maybe you're not too picky and just want some boom, in which case just about any sub/box combo will do.

[lowrydr310]

Originally Posted by Emilime75

Ported/vented vs sealed-

The general consensus is that the sealed sounds "tighter" than vented, but this is only so if the box and vent aren't designed/built properly for the driver.

Vented, if designed right, will be more efficient at and above the tuning frequency of the vent, i.e. you'll get more output from a vented system than you would from a sealed system.

Vented is more difficult to design and build. Sealed is very forgiving, i.e. a sealed box doesn't have to be exactly the right size, so a bigger variety of drivers will sound OK in a given box. For vented, box size and vent tuning/dimensions are critical per the driver chosen if you want a flat response out of it-in this case, "flat" is good, it means there are no large peaks and dips in the response of the driver.

For maximum performance, your best bet would be to choose the driver that will do what you want, then design/build the right box for it, or have someone experienced with this do it for you. The premade offerings take a lot of shortcuts and make compromises in order to appeal to many while meeting a budget requirement. Maybe you're not too picky and just want some boom, in which case just about any sub/box combo will do.

The specific product I'm looking at from JL Audio is called the "Basswedge" which is one of their W0 woofers already installed in a ported enclosure specifically designed for that woofer. I misspoke when I said Flat. I wasn't referring to the response, just that reviews of this product mention that any low frequency sounds too far away from the tuned port frequency are significantly quieter.

I'm not too picky but I've always been satisfied with my sealed enclosures. Looks like I might just stick with it again.

[Emilime75]

What the reviews are describing is what I've found with pretty much all manufacturer spec enclosures. They design the box to be peaky/boomy. This, in turn, is perceived as loud by most people, and gives the manufacturer bragging rights that driver x in box y will play z loud, but it actually sounds like crap because it's a one note wonder. The JL W0 is also their bottom of the barrel model driver.

JL does say the Basswedge line is available in both vented, and sealed. Maybe the sealed version might sound better?

[Ali-E90]

I had excellent results doing an IB setup with a JL 12w3. Had a JL 10w3 in a sealed box prior to that which also sounded very good.

The IB setup is very musical, accurate, and can play low. And is an easy-ish DIY for these cars. Look up the appropriate threads, I was pretty impressed.

[lowrydr310]

Originally Posted by Ali-323i

I had excellent results doing an IB setup with a JL 12w3. Had a JL 10w3 in a sealed box prior to that which also sounded very good.

The IB setup is very musical, accurate, and can play low. And is an easy-ish DIY for these cars. Look up the appropriate threads, I was pretty impressed.

I have never considered an IB installation before but I have seen the posts and it did interest me. Especially now that I have a ski pass through.

[Ali-E90]

Originally Posted by lowrydr310

I have never considered an IB installation before but I have seen the posts and it did interest me. Especially now that I have a ski pass through.

Easy enough that it's worth a shot, I've used two different subs in the IB config now and both sounded fantastic (12w3v3, IDQ12v2).

Let us know how it goes!

[Ali-E90]

If you go this route though, you'll get even better results getting one of the IB specific subs (unsure of price, but I know FI, SI come up often, and IDMAX also).
But any sub with low Fs, decent to high Xmax, and qts near 0.7 should work well.
But even without it, like the 12w3 I had, it can still sound great!!