Well, found something interesting with the Lightning...

Jstas

...as everyone knows it's running the old Polk dB series components and subs with Kenwood eXcelon power and sources. (BTW, got the PS955 fixed, the tech at Suburban Audio wanted to meet me 'cause he hasn't seen a PS955 in years, offered to buy it from me too!) Well, I blew a woofer. For real, the coil is scraping something, either pole piece or the magnet wall. Might just be the former but it makes a rattling click sound and it seems loose in the basket so I'm guessing the spider let go completely.

So I yanked the rear 6.5's out and replaced the bad woofer up front with one of the rears. I figured, this is the chance to see what difference it makes.

Well, it did make a difference but not necessarily a better one. I did not get any improved imaging and the sound stage didn't move forward but actually moved back. I had to adjust the crossovers to give the front speakers a full range where they were cut off at about 80 Hz before with the rear speakers giving the extra punch between 50 and 80 Hz.

Well, that dragged the sound stage to the rear and raised it up a bit. Not a good position IMO. I'm thinking it's because of the front speakers being forced to reproduce more low end frequencies than they did before.

Don't get me wrong, it still sounds spectacular but I think I'm missing the rears. I only have a set of 5.25 inch woofers from a component set I picked up so I'll put them in and see. I had to cut new brackets for the 6x8 inch holes and I gotta center the cutout and clean up the brackets. Then they get the rust cleaned off and painted with Rustoleum primer and Dynamatted out the wazoo.

Yes, I cut steel plates or aluminum plates rather than using MDF and fiberglass or plastic stuff. I have access to an unbelievable amount of sheet metal of all kinds. So I have high tensile stuff, basically the toughest sheet steel you can buy. A 4x16 foot sheet 3/16" thick runs about $1800 but it won't flex at all and it will last forever. We build dumpsters out of it. Either that or high grade sheet aluminum that we use for build intercoolers for the race cars. Very stiff, very light.

I broke a set of interconnects though so I gotta get a new pair too. I'm gonna throw the 5.25's back in though and see what happens. I think the biggest issue is that the Kenwood headunit I have can set the rear pre-outs to a non-fading state. Good for subs but I found that if I stick the mid-bass on there and boost the level two or three notches, it takes stress off of the full range up front and I can cross them over higher.

I could probably do more for the imaging by doing some custom work but I honestly, I like how it is now and the stock locations of the speakers are in a pretty good spot already. Getting stuff to fit is a bigger problem. Besides, I have the Ranger to do all the custom work I want and it's gonna need it!

MacLeod

Thats weird. Losing the rear speakers shouldve pulled the stage up even more and having them play lower should definitely have pulled it up front more as it would blend in with the sub better. Dont understand why not having rear speakers pulled the stage to the rear.

Jstas

I'm honestly not sure myself. I'm thinking that it has something to do with the fact that the front speakers are now doing full range where before they didn't do anything below 80 Hz. The woofers are in the doors, just below knee level. Can't get them on the kick panels because the drivetrain computer is on the passenger side and the parking brake is on the driver's side. The parking brake isn't that big of a deal but the computer is and since the Lightning has two units there instead of the one, it's difficult to fit a kick panel properly. I can't mount them lower in the doors cause I don't want to cut the door panels up and there really isn't room because the window mechanisms are in the way. The Lightning uses different and lighter mechanisms than a stock F-150. So the stock speaker mounts are where it's at in the doors.

Now I tend to get alot of reflection off of the dash panels right next to the speakers so I use that to my advantage and angle the tweeters at the dash. It widens the sweet spot and sounds decent from any of the seats but still gives that stereo imaging from the center seat because the off-axis response of the tweeters seems pretty good. I don't doubt it would score high in an SQ competition. I don't think it would win but it wouldn't be dead last if the microphone was placed where it is normally placed on the dash.

Anyhow, because the fronts are now pushing full range, I'm thinking the dash panel reflections are playing in to it. Since the rears are playing between 80 Hz and 40 Hz, they aren't that easily localize. They are also located pretty low and facing sideways across the cab too and off-axis response is kind of limited because they sit pretty deep in the pocket. So they aren't easy to localize. With nothing but mids and highs coming from the front and bass from the rear, it would probably push the sound stage backwards because everything that is easy to localize is coming from the front and off of the reflections.

I mean, the environment is no where near ideal and the installation is compromised for top quality in imaging but the dynamics, the detail, the accuracy and the depth are all there. I dunno. I'm gonna cut these panels and install the 5.25's and see what changes. Maybe I won't like it and I'll mess with crossover slopes and such.