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Quote:

Originally Posted by endeavour32 (Post 3029938)

For what John is trying to do that won't work. These are being used as Midbass and x-over at 80 hz and rolling off at 250hz. I like bandpass boxes but there big, heavy and not really ment for this type of application.

I'd suggests sealed box, then put around 150 watts to each of them. The w3's are not very effecient so their gonna like power. Then for your mids get another amp rated at 50-75 watts run it at two ohms for a total of 200-250 watts. This will give you 400 watts above 80hz and 500 watts below 80hz. The specs on your JL j2 1000 amp are 400 watts at 4 ohms, 700 watts @ 2 ohms and 1000 watts @ 1 ohms. Your W6 12 has dual 6 ohm voice coils. This will give a 3 ohm load and give you about 500 watts to the subs.

Also, I think I would stick with just 4 4 ohm mids. If you go with 8 your ohm load is going to be at either 4 ohms total or 1 ohm total. I think one set in the front and one in the back with the propper power will sound great.

Just remember there is no free lunch. 900 watts is going to want power. Your going to have to beef up the alt and probably add at least another battery. My 700 watt Orion set up would make my alt needle bounce when I had it cranked. I have a 65 amp alt. Now I'm upgrading to a 110 amp.

You have no clue at what I'm talking about.... I didn't say "bandpass box", I said bandpass crossover. That means setting a low pass at 250hz, and a high-pass at 80hz. You can't just high-pass a sub and expect it to "roll off". That sounds like TOTAL ****!

Quote:

Originally Posted by jonyb (Post 3030217)

LOL. JL Audio told him to let it roll naturally. They said it would do so at that range (250 hz). So I guess you should take it up with them and read getrdunn's post. You seem pretty angry man, go have a beer! You didn't say bandpass x-over, you just said bandpass! So be more specific otherwise don't get pissed if someone didn't read your mind and takes it some other way. Come on man, chill out, and lets help John have a killer stereo!

Quote:

Originally Posted by jonyb (Post 3029854)

And if you're not gonna use the low pass crossover, you should at least bandpass them.... That's using the high and low pass, to play only the frequencies inbetween.

Quote:

Originally Posted by endeavour32 (Post 3030233)

You didn't say bandpass x-over, you just said bandpass! So be more specific !

I couldn't have been any more specific.

Let if roll off? That's a joke.... I'll tell you that I've heard a sub try to play like that and it was awful..

Quote:

Originally Posted by jonyb (Post 3030237)

I couldn't have been any more specific.

Let if roll off? That's a joke.... I'll tell you that I've heard a sub try to play like that and it was awful..

I see you still haven't had that beer! JL AUDIO told him to let it roll off! In a personal conversation John and I had, we both agreed that he need to limit the lows and highs on the mid bass and then run a sererate amp to the mids. Further more if you've read any of the posts, these are being run as MID-BASS not SUBs. I agree you cannot roll of a sub, it will sound like crap! The difference between 60hz and 80 hz can be huge with subs!

Quote:

Originally Posted by jonyb (Post 3030237)

I couldn't have been any more specific.

Let if roll off? That's a joke.... I'll tell you that I've heard a sub try to play like that and it was awful..

That's funny, it is Saturday night though. I think it is about that time. Jony what the JL rep said was for the mids as in the two 8"w3's to roll off assuming they saw nothing below 80 hz. Hell I have no idea. I had even mentioned to him that idealy they would play at around 80 hz to 180 hz or so. Both the JL rep, Bill Barron and the guy from the factory had mentioned that about them naturally rolling off. Personally I thought if it was a stereo amp/full range they would have to be stopped at some point. Even thought they are used for mid base I would think they would produce highs. Not cool the ear either. Didn't really make total sense to me either however just what they said. Are there any amps that would be able to play "from and to" or do they just allow a starting xover point? Other thought was would need an electronic xover. I was thinking originally these should be mono however I was wrong there also. I am trying to help a friend out with his project as well. Also need to get the xs650's.

It was kind of funny actually the other day when I went to GR to take a tour of my old friend Pablo's new shop. Extreme Motoring. He started out as a radio installer many years ago and wound up with his own totally pimped out shop. I'm very happy for the guy. It was at the time I was there talking to him Bill Barron and the Factory guy walked in. Bill Barron use to rep for Kenwood back in the day when I was managing Remes Auto Parts. I was surprised he was still in car audio.

I use to use a really cool user friendly 3 way xover that was completely adjustable with dials. I can't remember the name of it though. Any ideas of a good one. Seems like the name was audiovox or something similar.

OK I had my first beer. :ernaehrung004:

So from what I am understanding then is that a set of 8" subs being used for mid base should only start and stop (2 xover points) at desired signal or hz along with a full range amp???

It's kind of hard to explain... The best thing I can recommend over the internet is just to low pass the 8's. Just because they're lowpassed, doesn't mean they won't have the midbass you want. I've got 2 DD 8's in my CTS-V that play around 125 hz and down, and it's amazing....

http://jonyb.webs.com/photos/04-Cadi...V/DSC_8176.JPG

John-
I was digging into the JL amps manuals and it looks like they have built in x-overs with outputs that pass the x-over signal up to the next amp. From what I can see you won't need a x-over as there built into your amps. Now you just need to figure out what size amps you need!

so with a DV 12" woofer running under 80 hz is it even necessary to run the two 8" as mid base from 80 hz up to 180 - 200 hz? Or would it just be recommended to run them say 125 hz and down with a mono amp? Hope this makes sense.

I guess what I am wondering is what would sound the best provided you have the six to eitht 6.5" for the highs.

gotta run those puppys in stereo.