Subwoofers

Re: 2 alpines or 1 jl audio sub?

TigerHeli — Thu, 09 Jul 2009 18:51:06 GMT

I think Namosh is running one, but can't find the thread on it.

Re: 2 alpines or 1 jl audio sub?

jthokie1992 — Thu, 09 Jul 2009 17:59:04 GMT

Anyone have any thoughts or comments on an Audio Control EpiCenter?

Re: 2 alpines or 1 jl audio sub?

TigerHeli — Thu, 09 Jul 2009 15:15:24 GMT

jthokie1992:
So far the 15" Alpine R sounds pretty good, hits really low but missing a little bit of the punch that the two Infinity 10" subs had.

I'm guessing that's just inherent with larger subs.

The Alpine sounds like it could use more power than the PDX 1.600 amp is putting out.

More power is almost never bad - but not the answer here. The sub is rated for 750W. You are at 80% of RMS and CF recommends at least 70%. A 900W amp would give you more headroom, but see this thread on going from a 650W to 1000W amp with two Type R's and I don't think it is justified.

One was to increase the line in voltage since only 2v is coming out the pre-outs of the Alpine receiver.

If I understand correctly - that would be a net-zero. Your input signal would be stronger, so you would reduce the gain on the amp to compensate and then you're back where you started. (Only exception would be if the gain was maxed already then that would help, but it shouldn't be). Line drivers COULD help keep the RCA's from picking up noise, but that's about all.

Other was to also rewire the receiver to the speakers to bypass the factory amplifier.

I recommended that previously, but that should help the mains, but not affect the sub.

Hope This Helps!!!

Re: 2 alpines or 1 jl audio sub?

jthokie1992 — Thu, 09 Jul 2009 13:50:04 GMT

So far the 15" Alpine R sounds pretty good, hits really low but missing a little bit of the punch that the two Infinity 10" subs had. The Alpine sounds like it could use more power than the PDX 1.600 amp is putting out. I talked to some friends here locally and some had suggested a few things. One was to increase the line in voltage since only 2v is coming out the pre-outs of the Alpine receiver. Other was to also rewire the receiver to the speakers to bypass the factory amplifier.

Re: 2 alpines or 1 jl audio sub?

TigerHeli — Sat, 04 Jul 2009 11:06:41 GMT

It was girlfriend in your post last week - there's still hope for you!!!!

(j/k - it was a joke honey, okay???)

Re: 2 alpines or 1 jl audio sub?

J Ro — Fri, 03 Jul 2009 18:24:38 GMT

TigerHeli,

Looks like the WAF factor doesn't apply to some ppl. Buying a 15 on a whim... sometimes i miss being single!

Re: 2 alpines or 1 jl audio sub?

blackchevy92 — Fri, 03 Jul 2009 16:27:56 GMT

Let us know how the Alpine turns out.

Re: 2 alpines or 1 jl audio sub?

jthokie1992 — Fri, 03 Jul 2009 14:47:45 GMT

Just a quick update. I got lazy and bought a prefab ported box for 2 10" subs to fit the infinitys in. It has 1.07 cubic feet per chamber with the port in the center between the subs. It made a huge difference compared to the sealed box they were in. They hit pretty hard now for their size. Shakes everything in the truck now, before it was a mild vibration with the sealed box, now the mirrors and everything else shakes. During my wait when I ordered the ported box, I also on a whim decided to order an Alpine Type R 15" sub and a Ground Shaker 15" ported box with 2.75 cu foot space for the sub. That is supposed to get delivered via UPS today and I'll see how that one goes. I am however pleasantly surprised with the two Infinity 10's performing so well in the ported box.

Re: 2 alpines or 1 jl audio sub?

TigerHeli — Thu, 02 Jul 2009 15:57:10 GMT

Bypassing the factory amp should help with the main speakers, but if they are stock, they might not be able to take the full HU power and might end up as the weak link in your system.

Hope This Helps!!!

Re: 2 alpines or 1 jl audio sub?

J Ro — Thu, 25 Jun 2009 01:17:29 GMT

I built a box precisely to what infinity suggested for a vented enclosure. I found it to be tuned a bit too high for my taste, and the tiny 3" ports were noisy. However, it was WAY louder than the sealed box, especially around 40hz.

A port needs some space between the opening and the wall of the enclosure. A good rule of thumb is a gap at least half the diameter. In my suggestion, the box would need to be 21.25 inches wide. There are different wisdoms about where the port should be on the box. Side firing ports have been growing in popularity, in conjunction with the growing popularity of lower tuning frequencies. The deeper you want the bass, the longer the port must be. It's no problem to have it on the side, but aim it towards a corner of your vehicle if you can.

Re: 2 alpines or 1 jl audio sub?

jthokie1992 — Wed, 24 Jun 2009 20:26:17 GMT

Thanks. I'll be sure to post up here on what I end up doing. If I build a box, would it be easier to go by the perfect 10 manual link you sent on an earlier post?

http://manuals.harman.com/INF/CAR/Boxes%20and%20Parameters/PERFECT10.pdf

Just wondering how deep the box would have to be to put in a 18" long port, unless I have the port firing out of the side of the box as opposed to the front or top of the box.

Thanks.

Re: 2 alpines or 1 jl audio sub?

J Ro — Wed, 24 Jun 2009 18:50:30 GMT

I hope you post again to say how it turns out. There is a certain satisfaction that comes from building the enclosure yourself. Namely, the satisfaction of saving money =)

By far the easiest way of constructing a port is by cutting a piece of PVC pipe. The SPL plot i linked was for a box 2.5 ft gross, with a 5" diameter port, 18" long. That would tune the box for your infinity's to 33hz, and move a LOT of air.

Re: 2 alpines or 1 jl audio sub?

jthokie1992 — Wed, 24 Jun 2009 17:20:31 GMT

Thanks again. My friend that did have the 13w7 in his truck did have it in a ported box. It seriously hurt to sit inside when he turned it up even half way. I'll have to save up a little to have a custom one built or I may try to build one myself once I figure out all the dimensions of the box and how to make the port.

Re: 2 alpines or 1 jl audio sub?

J Ro — Wed, 24 Jun 2009 12:36:33 GMT

Bear in mind, that SPL graph shows a SEALED 13W7. A ported one would be off the chart, and a danger to mankind. I think you've outgrown that pre-fab box. Find a professional installer in your area. Forget store bought boxes, look for a place that can build one for you. Let them know your goals. $300 is a reasonable price for a customized enclosure. The money you spend on the box goes farther than what you spend on the sub.

Re: 2 alpines or 1 jl audio sub?

jthokie1992 — Wed, 24 Jun 2009 04:06:55 GMT

Wow, its hard for me to imagine my 2 perfect 10's ever sounding louder than a 13w7. I am thinking about taking these from the sealed box and putting them in a ported box to see how they sound.