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Piraya33
12-04-2009, 11:13 PM
I have an 02' F-250 crewcab and I am mounting a JL 450/4 and a LC6i behind the rear seat. I want to know if I have to mount the crossovers for my front components close to the speakers or can I mount them behind the rear seat where the amp is and just run speaker wires from the crossovers all the way to the front door components? Thanks!

Front components are PG RSD65cs

jeeper07
12-04-2009, 11:55 PM
u can mount them back there and run wire from there. just make sure u dont use **** speaker wire.

Piraya33
12-04-2009, 11:58 PM
u can mount them back there and run wire from there. just make sure u dont use **** speaker wire.

I got this wire: http://www.caraudio.com/forum/showthread.php?t=436870

Seems to be pretty decent stuff.

ciaonzo
12-05-2009, 01:54 AM
Mount them as close as possible to the drivers.

Toone
12-05-2009, 01:59 AM
my ppi crossovers were massive so i mounted them near the amp and they sound great to me but im no sq head

misfit138
12-05-2009, 02:11 AM
Mount them as close as possible to the drivers.

This is something that I was always told when I first got into the hobby as a teenager, and I've seen it recommended in countless manuals over the years. However, I've mounted crossovers everywhere from glove boxes to trunks to door panel interiors over the years, and not once has crossover location ever given me problems.

I'm not questioning your knowledge on the subject at all, ciaonzo, so please don't take it that way. Maybe I've just been lucky.

EDIT: I've never really done a meticulous, expert level SQ install. Maybe if I were an expert in SQ I'd have a different opinion...

SRim23
12-05-2009, 02:16 AM
Mount them as close as possible to the drivers.

why?

I honestly dont think it matters. every set of comps ive ever had i have put them in the trunk by the amps with no issues. just make sure when you run the wires to make sure you know which are the mids, and which are the tweeters to avoid getting them mixed up.

SRim23
12-05-2009, 02:19 AM
This is something that I was always told when I first got into the hobby as a teenager, and I've seen it recommended in countless manuals over the years. However, I've mounted crossovers everywhere from glove boxes to trunks to door panel interiors over the years, and not once has crossover location ever given me problems.

I'm not questioning your knowledge on the subject at all, ciaonzo, so please don't take it that way. Maybe I've just been lucky.

EDIT: I've never really done a meticulous, expert level SQ install. Maybe if I were an expert in SQ I'd have a different opinion...

Im assuming that usually when it is suggested it is just a way to save some speaker wire.

ciaonzo
12-05-2009, 03:07 AM
why?

I honestly dont think it matters. every set of comps ive ever had i have put them in the trunk by the amps with no issues. just make sure when you run the wires to make sure you know which are the mids, and which are the tweeters to avoid getting them mixed up.


Im assuming that usually when it is suggested it is just a way to save some speaker wire.

Every component in your passive crossovers was selected to achieve a specific roll-off behavior based on the driver's resistive and reactive properties. Guess what else has these same properties? Speaker cable. Even the smallest run would introduce it's own unique set of inductive, capacitive, and resistive elements that were not present when the filter was optimized and will have an influence, no matter how subtle, on the end result. It may not lead to a gross error for frequency response (in fact, applying too much power (heat) to the voice coil will introduce a much more pronounced anomaly) but it will affect the time and phase coherency between the drivers. This would, of course, assume that you've gone to great lengths to ensure that the drivers were in optimal locations to preserve this relationship as well. If that's not extremely important to you and you don't value the ambient information or spacial cues in your recordings, then it's probably not a big deal. Honestly, most people have no idea what that really is, let alone how distinguish whether or not it's been compromised, and sadly most really don't or can't have the drivers in the best place to accommodate this performance. So some of what I'm saying is moot but I'm neurotic so I will continue.

It's bad enough that some people are forced into using passive crossovers and all their inherent flaws, poor damping being one of the worst, but why add to that problem with multiple long runs of cable between the drivers and the filters when you could just introduce one long run between the amplifier and the filters?

To be fair, this is one of those topics that gets debated as to whether or not the results are audible. I think some people can hear it and some people can't. I've designed many a passive filter and it's tedious work. I can hear extremely subtle changes not only in frequency response, but also in phase changes between drivers. I don't use passive crossovers in my vehicles but if I were to choose between mounting the filters in the trunk or next to the drivers, it would be the drivers on principle alone.