Newer car subs and older amps

[kpc01]

We are replacing the 12s in my wifes car and I have an old rockford punch 800a2 amp thats still working great so don't want to change it. The guys I've talked to said I need to get 8 ohm speakers since they use monoblock stuff now.

Can someone help me out in understanding. It looks like we'll be getting 2 JL 12w3 subs but should I get the 8 ohm or can you do 4 ohm and wire it differently? I've been out of car audio for too long evidently.

[EW]

You can read the manual on rockford's site to see how low it can run. Most modern sub amps have the most output at 2 ohm mono. If your amp will only go down to 4 ohm mono, you would have to buy 2 12W3v3-2 and wire them in series. There is no longer a 12W3v3-8 available.

Looks like it is a 2ch amp that will run 4ohm mono.

[BMCSean]

I have a setup I will let go cheap if you decide to get a new amp. Diamond audio 1000.1 amp and power acoustic 2400w 12.

[kpc01]

You can read the manual on rockford's site to see how low it can run. Most modern sub amps have the most output at 2 ohm mono. If your amp will only go down to 4 ohm mono, you would have to buy 2 12W3v3-2 and wire them in series. There is no longer a 12W3v3-8 available.

Looks like it is a 2ch amp that will run 4ohm mono.

Thanks for the info, so I need the 2 ohm speakers? Also will my sealed box I was already using work?

I have a setup I will let go cheap if you decide to get a new amp. Diamond audio 1000.1 amp and power acoustic 2400w 12.

I'm hoping we can make this work as we're not really trying to spend money on it....wife had a wreck and the speakers got broke so we are just trying to get it back to what she had, but if I can't get the JLs I need or a decent price I'll let you know

[BMCSean]

Thanks for the info, so I need the 2 ohm speakers? Also will my sealed box I was already using work?



I'm hoping we can make this work as we're not really trying to spend money on it....wife had a wreck and the speakers got broke so we are just trying to get it back to what she had, but if I can't get the JLs I need or a decent price I'll let you know

Sounds good LMK, I'll make you a hell of a deal also I'm not too far from you if you want to check it out.

[kpc01]

Is this the wiring to use using it as a 4ohm?

If so, which + and - on the amp do I come off of?

http://a248.e.akamai.net/pix.crutchfield.com/ca/learningcenter/car/subwoofer_wiring/2dvc_2-ohm_mono.jpg

this is what I found with 4 ohm but it wouldn't sound as good right?

http://a248.e.akamai.net/pix.crutchfield.com/ca/learningcenter/car/subwoofer_wiring/2dvc_2-ohm_2ch.jpg

[EW]

Neither of those is correct for SVC (single voice coil) wiring. With most amps, you will use the left positive as the positive and the right negative for the negative.
None of the Crutchfield diagrams show the 2 ch amp bridged. You can do this:

http://a248.e.akamai.net/pix.crutchfield.com/ca/learningcenter/car/subwoofer_wiring/2SVC_2-ohm_2ch.jpg

JL recommends 1.321 cu ft of airspace per woofer for the 12W3v3-2 when you add the driver displacement. If your sealed enclosure is near this size, and well built, it will be fine.

[kpc01]

thanks again for the info. I will see if I can get the measurements of the box and also figure out what we want to do with wiring. So you recommend getting the 2 ohm speakers and wire just like the link you provided? We are going from rockford HE2 subs so the JLs hopefully will be an upgrade as it is