Need some Tuning Help

[jf2oo6]

Need some help with tuning this system.
I will be using a pioneer P4200DVD, and a Sundown Sae-1200D.
Stock speakers for now.

Im wondering how to set the crossovers for the sub. The head unit has high and low pass filters built in so should I just use those? In the manual for the head unit it says frequencies lower than what the low pass is set at will be sent to the sub, and frequencies higher than what the high pass is set at will be sent to the speakers. So if I set both of these at 80hz I should be good right?

Also how would I set the x-overs on the amp. Here is what it looks like.

[jf2oo6]

anyone?

[89grand]

80hz is a good starting point. And yes, I'd use the crossovers in the head unit, because it's a lot easier to adjust while listening to the system. It is possible though that the amps have a better crossover however, but anyway, if you use the head units crossover, just turn the amps crossover all the way up since it doesn't appear to be defeatable.

[jf2oo6]

Ok so please tell me if I have this right.

The X-Over on the amp max frequency that it will send to the sub, and the sub sonic is the minimum frequency it will send to the sub?

So if I used the hu I could just turn the x-over to 250hz and sub sonic down to 15hz correct?

So the only thing Im confused about now is what to do with the phase switch. Someone please help me understand what that does.

Thanks Guys

[89grand]

Tes, set the head units crossover to 80hz, low pass and high pass. Then set the amps crossover at 250hz. The subsonic can vary, if you have a ported enclosure, set to about 25-30hz, if it's sealed, I wouldn't worry much about it so 15-20hz is fine.

The phase switch just flips the polarity on the subwoofer. Sometime the sub blends better at 0, sometimes it blends better at 180 degrees, try both and see which one sounds the best.

[jf2oo6]

Ok thanks. Last thing Im wondering is for the gain. Should I just do it by ear, or use my DMM. I read on JL's site how to do it with a DMM, but they give the voltage for their amps. How do I know how much voltage I need on my Sundown.

[89grand]

DO NOT do it with a DMM. In fact, since you are running a stock system, just dial in the sub to fill in the bottom end by ear. Don't worry about where the gain control is actually set at.

[audiogodz1]

If you are setting mids and subs on a crossover tune the mids crossover to 25-30 hz above the sub. So if you are at 80hz on the sub, set the mids at 105-110hz. This will give you a nice smooth transition point in the middle as the curves fall off, otherwise you'll have a boost at that frequency if all speakers are playing the frequency.

[89grand]

I think that depends a lot on the install. Typical trunk mounted subs may experience roll off below the crossover point of 80hz depending on the density of the back seat and what not.

I'd say start out at 80hz for each, then experiment from there. Maybe your system requires an underlap like described above, maybe it even needs an overlap. Maybe it need neither. All installs are different, you never know for sure.

[Knobby Digital]

Originally Posted by audiogodz1

This will give you a nice smooth transition point in the middle as the curves fall off, otherwise you'll have a boost at that frequency if all speakers are playing the frequency.

Depends on the alignment of the XO. Usually overlap is accounted for.

But the numbers screened around the pot of an amp aren't accurate and very close together, so it's hard to know what's going on if you're doing it that way. So I'd use the HU, instead.