Look what Brown did for me today...

[IZVERG]

Mr. UPS just dropped off for me my brand new, carpeted 10" sub box and brand new Alpine Type R 10" subwoofer. I absolutely loved this sub but it was stolen from my first (of two) X break-in. I replaced it w/ a 12" Audibahn than I got dirt cheap from a guy here on base but it's honestly too much thump for me, not to mention how huge the friggin' sub box is! Takes up way too much cargo space for my liking. I found a great deal on these two off of eBay (both w/ shipping was under $175). Can't wait to put this bad boy in the X...

The before


... and the after. This is an EXCELLENT sub box, very good quality, sturdy, and just overall a great deal (if anyone is in the market for a sub or box PM me and I will get you the eBay seller's info).

[robust57]

Congrats. What kind of wattage are you planning on putting to the sub? Box location?

My audiobahns have too much thump too and my box is huge (that's what she said) as well.

[IZVERG]

--That's what she said-- I was wondering who would bite!

I will just be swapping out the old for the new in the same place: ratchet-strap secured directly behind the driver's side rear seat, seen here:

[IZVERG]

Oh, and as far as wattage goes I'm not real sure. It can handle up to 1500W and I have a RF Punch P400-2 amp powering it @ 100 RMS watts per channel x 2 @ 4 ohm and 400 total RMS watts at 4 ohm... whatever that means (I just copied from the box)!

[robust57]

Looks to me like that ratchet strap would cause some limitations to the excursion of the subwoofer, but it doesn't sound like you have any complaints. I used the cargo rails/track to secure my sub box, but its the full width of the cargo area.

That amp that you have and the sub you bought I don't think pair together too well for a mono sub application, but I could be very wrong. If the amp can be bridged into a 2 ohm load then it would be perfect but since it doesn't appear to be stable with a bridged 2 ohm load the sub isn't going to see much wattage. If you put the voicecoils into parallel it would be a 2 ohm load, if you put them into series you would see an 8 ohm load. I don't think you can just wire each voice coil to its own amp channel, I just don't know. If you can then it would work out awesome as each coil would be its own amp channel seeing a 4 ohm load.

[IZVERG]

Yeeeaaah, that was all some foreign language to me! Are you basically saying that the amp would be sending too much power for the sub to handle? I was going to try and wire it up myself, all that needs to be done is get the sub drilled to the box and do the internal wiring as all of the other stuff (wire to amp) is already there - but now I'm not so sure!

Any pointers? It came w/ these two little cables - one red and one black - that I'm supposed to plug into the two or four inputs on the sub itself. Then what do I do as far as wiring the sub to the brackets on the inside of the box? Where I plug the wiring to the box on those gold plugs on the back of the box?

[cjm_specv]

robust57 is right. Your Alpine SWR-1042D is a dual voice coil sub (4ohm per coil). The proper way to wire it to a 2 channel amp is bridged (see Crutchfield link below). If you wire it in any other fashion you risk damaging the sub, the amp, and/or both. As the diagram shows, bridging the amp results in an 8ohm load. Your sub is rated at 1500W peak power and 500W RMS. I will not get into the specific formulas for calculating ohms and watts, etc., but in a nut shell the lower the ohm load, the more power the amp will prodcue.

Typically a dual voice coil sub is meant to be paired with a mono channel amp. The advantage of a dual voice coil sub is that you can wire it in parellel to a mono channel amp and reduce the ohm load on the amp (thus increasing the power output of the amp). I have a dual voice coil sub (4ohms per coil) paird to a mono channel amp. The amp produces 400W RMS at 4 ohm and 600W RMS at 2 ohm. Therefore, the advantage of having a dual voice coil sub allows me to wire the sub to the amp in parrellel (dual 4ohm voice coils wired in parellel produce a 2ohm load) thus sending 600W to the sub.

All that being said, you can wire your sub as indicated in the diagram resulting in the 8ohm load but at 8ohms you will probably only be sending roughly (and I say roughly becasue I am too lazy to do the actual calculation) 150W RMS to the sub which is about 1/3 the power it is capable of handling.

http://akamaipix.crutchfield.com/ca/..._4-ohm_2ch.jpg

[robust57]

Sorry. No it will not be too much power to the sub. That sub probably has a 500-750watt RMS rating, if anything it will be underpowered but that's not a bad thing since it won't be really underpowered. The sub should have a spec sheet that says the lowest amount of wattage that it needs to opperate, probably around 100watts.

What can happen is that an amp will overheat if it can't support a lower load. I had my subs wired into a 1 ohm load and my amp would shut off after about 20 minutes of thumping. So I rewired things and now have a 4 ohm load, much more stable and the amp doesn't shut off.

I did just learn that you can wire each coil to its own channel, perfect for you. Here's my source of information. http://www.crutchfield.com/learn/lea...fers_dual.html

So what I would do (you probably won't like this) is to either remove that termination point in your box and get a 4 terminal unit. So that there's 2 negative terminals and 2 positive terminals. Or get a second 2 terminal unit and install that into the box, wire as noted in my sweet paint picture.

[IZVERG]

Yeah, that looks just like the diagram that was in the box. So I will be OK as long as wire it like that, bridged, with both cables?

[IZVERG]

I'm just gonna have Bet Buy do it for me manana, save some headache and let the pro do it.