You be the man who knows more than I ever will...

I am looking at replacing the single 10" in my 92 with a pair of 8" subs in the rear enclosures.

The rear speaker spaces are about .4 cft. A little polyfill can help, I suspect. I intend on reinforcing the insides of the enclosure.

I am leaning towards JL Audio 8W3v3...

Any thoughts?

 

There is no such thing as an 8" subwoofer. ibtspkrboy

 

I have been wondering the same thing, which brand would you suggest?

 

I'm curious why? Is it a space issue?
Although 2 8s will provide you more surface area than a single 10, in general a 10 will play lower than a single 8.

 

Sorry but this is just a subjective opinion. I can't make any recommendations because I am not that familiar with car audio but of course there are 8" subs. I've seen line arrays with 3.5" subs that are quite impressive. Subwoofer is a "relative" term. The only difference between an 8" sub and an 18" sub is the output capacity, not the frequency response capability.

 

That's a pretty effective way to get my attention, there, Bogus.

What Robvuk says is gospel. The intent and design of the driver are what matter.

Diameter doesn't matter when determining which will 'play lower.' In a given box, the smaller driver (all other things being equal) will have a lower Fb and F3. Overall output is where things get dicey. Don't confuse loud with low.

That's Kale just trying to get me fired up. He knows better.

Care to elaborate on what your intended goals are? The rest of the system components? They can change my recommendations quite a bit.

I tested the 8W3v3 a while back and found it to be a very nice driver, but quite over-priced (typical JL). If you have the $, it's a decent choice. The drawback is their low sensitivity. The ARC 8s Kale references a lot appear to be decent drivers as well. There are a few OEM drivers that might suit your needs at half (or less) the price. Depending on your technical abilities, I'd have a few other suggestions.

Word of warning... I'm not one to buy into the "bigger, lower and louder" mentality of car audio, so my suggestions may send people screaming about heresy.

 

ARC 8s f3 in .42 of space is 53hz. ID8 is an identical sub for about half the price.

F3 of the JL dirver is 66hz. That means at 66hz you will be down 3 decibel. At 53hz, 5.5db. (meh)

So the ARCs should play lower for you. What do you think, Spkrboy?

 

3db down from what reference frequency? And what's the intended crossover frequency?

 

0 is @ 184hz on the ARC/IC
0 is @ 221hz on the JL

Both start to really curve at 80hz or so

 

The point is that both speakers are probably a db or two down already at the crossover point in which they will be used. As subwoofers, they will never see 200hz. Additionally, if 80hz is the crossover point, depending on the crossover design, they will be at least 3db down at that point. Subwoofer frequency response is almost insignificant because they only work in basically a one octave range. What you should be more interested in is, if they are built into a properly designed box, if they have comparable sensitivity (in the 40-80hz range), and if they will provide the output capacity you desire within their power handling capacity or Xmax.

If you've ever seen the response plot of a subwoofer AFTER the crossover, you'd notice that they are ALL very similar humps in output. Some having a little more output below 40 than others.

 

Relax, gents... those numbers have little to do with reality. Assuming Kale's using WinISD, the effects of cabin gain, crossover, relative sensitivity and other smaller factors aren't considered more than just generically. The resulting simulations are intended for free-space comparisons.

Let's hold off until we have more information from Bogus regarding his intentions.

 

Thanks for all the comments/replies! This has really lit of a firestorm (for CF Audio) of discussion...

This is for my 92 coupe. I currently have a 500/5 amp (which has a 250 watt mono output for sub(s)), but that is subject to change.

The goal is to build a system that will provide good musical punch, but not take up all the space of a 10" - I currently have a 10W3v2 in a sealed box.

The head unit is an Alpine 7998.

Call this, ultimately, an experiment.

 

I don't remember how far you are from me, but you are welcome to listen to my ARC 8s any time soon... I'm ditching them for a 12 at the end of the month though.

*edit. Found your zip code. Nevermind.

 

Questions:

What sort of musical tastes?
At what volume levels?
Price limitations?
Do you know enough about box-building to interpret an impedance curve to tweak?
In car audio, you get two of these three conditions: Loud (efficient), Low, Small Enclosure. Because you've chosen the enclosure volume already, you have the remaining choice of louder or lower (you can't have all three).

 

yea, Kale... I ain't gonna make it up there on lunch hour.

To answer your questions, spkrboy:

1. Rock, anything from Metallica to Jimmy Buffett.

2. Moderate. I have never been into deafeningly loud.

3. Irrelevant. I will save up and wait.

I can build a box, that isn't a problem, however, the words you write make no sense to me...

Lower. I would prefer more frequency response than pure volume. The smaller cabin allows for less volume, so I get the luxury of going after quality over quantity.

 

Our tastes are similar enough that I don't think you'll be disappointed with the following alternatives, in order I'd personally try:

1. Silver Flute W20RC38-04 At $32 and considering it's efficiency rating, this is worth the potentially-wasted $. Surprisingly, this driver will respond well in those factory locations, vented with a 2"x5" port. It'll do very well down to 50 Hz, and drop off like a rock.

2. Dayton QT210-4 Also worth a shot at $44 apiece. Sealed 0.4 ft^3 gets you a Qcb a little over 0.71. Very similar response to above without the efficiency.

3. Dayton RSS210HF-4 $88 apiece. Very sturdy driver that will play lower than both above but with less efficiency. The Qcb will be about 0.8. and an F3 of 49. For your taste, that's about the correct Q.

4. Peerless-Vifa P22WR09-04 $98 each. More expensive than the others, but one of my personal favorites. Qcb will be about 0.8. F3 will be about 59.

Don't judge any of these by their appearance. They're not meant to look like car subs and that 'look' has nothing to do with performance.

 

have heard nothing but good things about dayton drivers.

 

that's an interesting list! Thanks for the research!

I am leaning towards one of the daytons....

A forum member, nelson v. had a pair of JL Audio 8w7v2s in his C5 roadster... damn, those sounded nice, but they need a ton of box space.

Another friend had a pair of Boston 8" subs in his pickup, what they lacked in punch they made up for in SQ. I think his lack of amp killed it a bit.

 

As you're seeing with the examples you provided, there's no 'free-lunch' with subs. You can't have efficiency, low response and a small enclosure all at the same time. You really are left with choosing two of those three criteria.

JL subs have always been notoriously power-hungry. You get low response and a small box, but lousy efficiency. There are lots of different car-intended subs out there that might work as well, but you're going to pay more than the above prices for them or you'll be getting something with low long-term reliability or other compromises.

After thinking a bit longer, I think the Silver Flute and the Dayton RSS210-HF are your best bets from the OEM world without getting extravagant. The Silver Flute will sound very good in your car, and cabin gain will help it tremendously. The Dayton will require substantial amplifier power. If you run across other subs that might interest you, link them here and I'd be happy to stamp them one way or the other.

Good Luck