traderfjp

Hi - I am installing JBL 6 x 9 speakers in the door, 3.5" 2-ways in the top of the door and 5.25 speakers in the rear. I have a 4 channel X power Alpine amplifier which I want to use to power the 6 x 9 door speaker and the rear speakers. The 6 x 9 speakers can handle lots of power. However, the 3.5" speakers don't. I'm not sure if I should let the Kenwood dnx890hd hu power the 3.5" speakers or wire them in series with the 6 x 9 speakers. I'm worried that the 3.5" speakers will not be able to keep up or even breakup if I play my system too loud. Letting the HU power them would allow me to eq each set of speakers and just use them as fill. Not sure if there is a better way.

I also was wondering if the center channel speakers is needed for chimes, etc. or can I disable it. If not I'll power it with the HU.

Lastly is there a cover or something that fits over the HU to keep thieves from seeing what I have? Thanks in advance.

FAUEE

Why are you replacing 10" woofers with crappy 6x9s? IMO, you're better off replacing them with a legitimate 10" speaker if you're going to do anything, you're going to drop a LOT of cone area (and a lot of bass) by going from a 10" sub to a 6x9 full range. Not to mention the distortion caused by an oval speaker.

What I'd do is use the 4 channel to power both front speakers, and run the 5.25s off the deck. Rear speakers are rear fill, and don't really add to the staging of the stereo, and in fact in a lot of cases they detract from it. I'd run them as low power rear fill, or just not run them at all.

Good luck

traderfjp

I'm also planning on installing a subwoofer so the "main" speakers will only have to go down to about 60-90hz. They don't make a 10" woofer that would have the correct depth for the door and then I would have to buy crossovers and use the 3.5" speaker for the highs. I'm not sure I would gain much and it would be a much more complicated install to tweak.

FAUEE

Sure they do, you're just not looking in the right paces

There's any number of name brand slim fit 10" subs (JL, RF, Kicker, etc. all have their own), as well as some gems that are more targeted towards the DIY crowd, like these:
http://www.parts-express.com/pe/show...number=264-862
http://www.parts-express.com/pe/show...umber=264-1105

Your amp should have crossovers built in, you'd just have to set the LPF on them (easy to do). The you'd run the 3.5s with a HPF, also built in to the amp.

You'd gain a lot. Better imaging, more cargo space saved, less weight added, more stealth look so people won't be interested in stealing anything, and overall better sound quality.

People who build sound quality cars dream of having 10" speakers in their front doors, and go to insane lengths just to get 8" woofers in their doors. Putting 6x9s in place of 10s is a major step backwards.

traderfjp

Those links are for 10" subwoofers. Subs put too much energy out to be mounted in a door, imho. Also, a great driver will sound terrible if it's not in a properly braced enclosure that is properly sized. I would also be worried that it would rattle the heck out of the door. The drivers you mentioned roll off at about 400hz. I still need to cover from 401hz to 22hz. In a perfect world they would make a 10" slim mounted 3-way speaker or even a 2-way. Now I guess in theory you could do the sub thing and then use a pair of 3.5" drivers for the midbass. Most of the 3.5" speakers don't handle all that much power and my gut tells me it would be hard to match up to a power hungry sub driver. Is this a setup you have in your Vette? I also heard no distortion with the oval drivers. In fact I ran these JBL's with my home amp and they sounded great and are rated very highly. In fact they exhibted good bass when played in free air. I was surprised. The midbass and hishs sounded good but once they are mated to a sub and adjusted properly I think I will be very happy.

FAUEE

6x9s (and other oval speakers) by their very nature have inherent distortion. Because the cones are not circular, there are not equidistant rings in the speaker, and so there is inherent distortion from having a driver that is putting out some sound from points further out from the center than in the other axis. I'll gladly note that this is not knowledge I am 100% sure of, this is just what people who claimed to know a lot more than me about it have said - I'll let someone here who's an acoustic engineer decide if this explanation is true or not.

But yes, those are subwoofers. The 10" speakers in the Corvette OEM are also subwoofers. The 8" speakers in the non-Bose system, are subwoofers as well. You end up running the 3.5s down to wherever you need to, and let the subwoofers do their job free from the need to play higher frequencies.

You don't need to feed as much power to the 3.5s, as they will be MUCH more efficient, and have a much higher sensitivity than the subwoofers. It takes a lot less power to make those higher frequencies than it takes to make the crushing lows people want.

The OEM subwoofers are run in a setup called infinite baffle. Basically, there is no enclosure - but in a more technical level the rest of the world is the enclosure. It's a fairly common setup nowdays, you just have to make sure the drivers are capable of being run IB.

I don't have this setup in my Corvette. Truthfully, I'm satisfied with the Bose sound in mine, because it serves only as a filler for the real sound system, the NPP exhaust But the subwoofer + midrange combo does work very well in other cars I've built (did installs for 5 years in a prior life), and actually a lot of sound quality competition winning vehicles run setups similar to that.

One thing I learned in my prior life is that people have vastly different tastes. I'm lucky, I'm not particularly picky about audio compared to a lot of enthusiasts. A lot of people are way less picky than myself, we did basic installs with a new deck and some crappy coax speakers and people were blown away - all a matter of expectations and requirements I suppose. Basically what I'm getting at is that you very well may be satisfied with your setup, it's all a matter of what your personal requirements are. I'm just giving generic sound quality improving advice, that may or may not matter to you at all.

traderfjp

The setup you descirbe is very intersting. Th eone caveat is the subs have huge power demands. Their sensitivity is around 81db while the 6 X 9's are 94db. That is a huge difference. Every 3db is doubling the power requirements. Anyway. I am coming from a BMW 335d and have bluetooth and Nav so I guess I'm spoiled. These double din HU are not too expensive until you add NAV then the price spike up quite a bit. It'll be a learning experience.

Nosferatu

I'm out and on tablet but if I have time later I'll pull up the link. I asked this last month. Search threads started by me you'll find the thread.

FAUEE

It's funny, I remember the first nav Unit to break under $1000, the AVIC-D3. We all swore that it was the lowest priced nav unit we'd see, and were amazed that it was decent too. Now it's possible to get a pretty darn nice Kenwood with Garmin nav for like $600.

I feel the same way though, my Jeep Overland had Garmin nav, full Bluetooth with a2dp, a built in hard drive, Sirius travel link, backup camera, an Alpine stereo, all that sort of fun stuff. My vette has Bose and a somewhat functional Bluetooth handsfree.

Anyways, the trick with the subwoofer is that it doesn't NEED to be maxed out on power. It will be more efficient at the low frequencies than the 6x9, so while its sensitivity is lower(which is a measurement all the entire range of frequencies it can play - and higher frequencies are MUCH easier to reproduce so they take less power), its frequency response will be better at the low frequencies, meaning you'll get more and deeper bass.

Downside is it'll cost more, the subs aren't as cheap as most pairs of coax speakers, and you may have to invest more in sound dampening.