How to go active?

[DemonAstroth]

For some reason I've had some troubles lately with my sound. Specifically the rear channels. Since when I go around bumps and stuff it gets worse, I think it has to do with the wiring. Now, I am going to clean up the wiring and everything else in a couple months (when I have money to put the amps in a false floor and the box gets to "fill up the rear"), but for now I have had to simply cut out the rear speakers (db6500).

I have heard from a few of you that going active will really improve the sound, so I would finally like to try while I wait. Who knows, maybe I"ll end up installing my other amp just to have rear speakers.

The front speakers that I want to do this with are some Alpine SPX-177r. They're old, but they do sound good. Probably nothing compared to SR6500's, but those should come later. :)

The amp is an Eclipse XA4000. I think the specs are like 125x4 @ 4ohm RMS.

So, what do I do? Do I just plug in the front output to the tweeters, and the rear output to the woofers? Ditch the crossovers?

My crossovers have an input for tweeter and woofer I think, so maybe I keep using them? I don't know... but any info will be greatly appreciated.

:D

[Toxis]

to go active means you need to have an active crossover therefore yes, you would not use the passive that came with the set. You have a lot of ways you can do this. A new headunit with the crossover capabilities (Pioneer 880 or 800, Clarion 9455 IIRC...) or a sound processor (RF 360, Alpine 701 combined with a compatible HU etc). Adding rears might complicate things if you go the HU route but for a processor, you should be good. If you're going for ultimate SQ, why have rears at all? The way I see it, rears are good ONLY if you have people ride in back for long trips. If its just around town kind of stuff, you can turn it up for them to hear in back or typically, you're talking as a group so you'd have the radio down anyhow. How many times are people in the back with music going at a low volume and they can't hear you because the speakers are right at their ears where yours are at your knees. Not to mention, it's hard to tune for a true imaging system... :)

But before you attempt to go much further, you will want to do as much research as possible! Placement is more critical than crossover settings IMO so going active can help SQ but not as much as having speakers where they should be. Get over to www.diymobileaudio.com and search around. There's thousands of threads about this subject. Sure a lot of guys here know their stuff as well but there, it's already posted so all you have to do is read instead of wait for someone here to respond. Hope this helps!

[DemonAstroth]

OOh yeah, of course. I have an Eclipse CD7100 for now.

My speakers will not move. I really like the stock locations. Woofers are by my knee and the tweeters are in the A pillar, they're behind the stock grilles but they are facing towards me.

I should def read more about it.... I just didn't know where to start, thanks for the website.

[TallTexan]

Some amps have enough built in crossover to do what you want. The Eclipse XA4000 stops at 500 Hz. You need one that will get closer to 4K or 5K. Example amps include the JL 300/4 and Polk Momo C400.4. Also for really little money, the Cerwin Vega EXL-400.4 will run active for you. Otherwise, a processor or head unit is in order although there are some external electronic (active) crossovers that will help do the active bit.

I've used the JL and Momo mentioned above. Once you have gone active you'll never look back. I was very pleased with it. Although, for me, properly deadening and sealing my doors made quite a bit of difference in mid bass.

[DemonAstroth]

I have already deaden the doors and the trunk with Dynamat extreme, i just wanted to tinker with the settings.

I guess when I said I was planning to go active it appears things got really serious. I would use the crossovers on the head unit most likely though. So the front channels will be the tweeters and the rear channels will be the woofers. The wiring should be a snap, I just need to know what would the crossover settings need to be, and what to set first, the xovers or the gains in the amp.

[candaddy]

You would set the crossover settings first. Try 4000hz for the mid to tweeter step and something like 80 or 100hz for the subwoofer to mid crossover point. Then set your gains. Unless you have good information on your speakers or somebody experienced with them chimes in, I wouldn't go too low with the tweeter crossover point or you risk damaging (destroying) it. If you know the crossover point of the passives you're getting rid of, you could copy that also. Set your sub gains, then mids, and tweeters last. That should get you well into the ballpark. If the subs are too loud for the mids, then set the mids first and subs and tweeters last. Just never set the tweeters first ;)

[DemonAstroth]

I set the tweeter (more on why just one later) at 3500 and it seemed to be the best point.

I completely turned off the subs in order to better listen to the tweeters and mids. So I think I should be fine with the tweeters, obviously once everything is plugged in I should be able to perfectly hone them.

When I was passive, I had the subs cut out at 120 with a 12db/octave slope, so since nothing changed there, I'm not even going to mess with it.

But now for the woofers (i guess I'll call them mids), I need to have two cutoff points (for them not to play ~ anything higher than 3500, and anything lower than 120). With the head unit I can easily do the lower filter, but not both. So should I use the amp's low pass filter for the highs? I wish I could do everything with the head unit.

Anyway, thank you (i did it just by ear and chose 3500, so I"m happy to know i'm in the ballpark of someone that knows more than I do).

[DemonAstroth]

I thought I'd need to buy a different amp.. silly me! I was getting quite distraught.

I just found out I needed to change the settings in the head unit from F/R/S to H/M/L, so that the mid can have both crossover cutoffs (hpf & lpf) and then I don't have to do any of the crossovers from the amp.

Now I just need to know why everytime I connect my left tweeter I hear this really sharp buzzing sound and the clipping light on the amp starts to light up. :( That and it's much much lower in volume than its right counterpart.

[candaddy]

Is there a short somewhere? Speaker wires crushed or something?

3500 is usually safe, it's when you go below 3000 with most 1" tweeters you'll start to push the limits. Generally speaking, the higher quality the tweeter and the larger the size (1" rather than 3/4"), the lower you can go with it, but don't get greedy, if 3500 is working, I'd say stick with it.

[DemonAstroth]

Well, I found out the reason of why things started sounding funny (and why I started experimenting in going active).

I plugged in the mids, sounded fine, I plugged in the tweets, and it sounded fine... or did it? I could really hear only one side. So I checked and the driver's side was definitely much lower. I swapped the outputs on the amp to make sure it wasn't the amp, and same thing happened, so I thought something was wrong. I got one of my rear tweeters (DB6500) and tested it and it sounded fine, so I knew it had to be the wiring.

Sure enough, as soon as I popped out the A pillar, I saw that the electrical tape which wrapped where the solder plugging the tweeter from the wire, was loose, and both contacts were touching each other and grounding on the chassis.

So my tweeter is out of comission. It's strange because it still plays, just at a VERY VERY low volume level. It doesn't sound distorted, but there were some popping noises before.

Now, my question is: I bought a cheap set of components (MB Quart PCE-216 for 80 bucks). Since I'm not going to use their crossovers, is it OK to just have the tweeters paired with the type x 6.5's? Or will the crossover points kill my sound?

This is just a temporary fix as I am really planning on getting some SR6500's, I just cannot afford them right now.

I'm pretty tired of this ordeal, I just want my car sounding right again...but I guess that's a way to learn.

[candaddy]

I'd try it and see, you already have them, so why not?