Evo VIII install

[AWD PSI 10+ year member]

I did some weighing of sheets of foam and Dynamat left over and came up with an approximation of the weight added. I'm not complaining but I am curious. I didn't weigh some of the pieces until half way through, like the amps before I put the seats back in so I got the figures from Amazon.com. They listed a shipping weight and product weight, I went with product weight. I know this won't be an exact figure as I have to guesstimate on some stuff.

8lbs...Alpine MRP-F300 4ch amp (seems high)

5.3lbs...Alpine MRP-M350 mono sub amp

10.8lbs...6 sheets of Dynamat Xtreme, (both doors and misc interior panels)

4lbs...2 PVC closed cell foam kitchen mats and plexiglass, (both doors and b-pillar panels) the mats were a little over 2lbs each, plexi was a couple ounces, after subtracting the pieces of foam and the plastic weather shield removed from the stock door, added to the scraps of trimmed mat left over I figure 2lbs made it into each side of the car. The blue camping mat squares I put behind the door speakers only weighed a few grams each, maybe a half ounce so that was negligible.

5lbs...2 Front door speakers and xovers. Stock speakers weighed a puny 2lbs, DB6501 weighed in at a manly 4lbs, add another lb for the xovers which I didn't weigh and the tweeters which felt a little heavier than stock but I also didn't weigh. Amazon lists the comp set at 10lbs which sounds about right. I didn't use the polk speaker grills or tweeter mounts so 5 sounds fair to me.

2lbs...2 rear deck coaxial. Same speakers in the front so stock is 2lbs, replacement db651's 3lbs.

5lbs...wire and connectors. 50ft of 14ga, 8ft 4ga, 6ft 8ga, 6ft rca cables x3 and a remote wire, spade connectors and ring terminals on everything, fuse holder on battery wire and fused distribution block. Weighing leftover pieces I gather around 5 lbs should be close enough, I guess.

Total 40.1 lbs

What does this mean? Nothing. I'm glad it wasn't 80 though. I might get close to that when I'm done adding the sub and enclosure (amp and wiring is already factored). The upgrade in sound and in cabin comfort was worth the weight, plus looking at the mod list already on the car, who knows how much weight I've already added, rear strut bar, bigger anti sway bar, croxx plate up front plus JVC HU and ipod/sat radio adapters and engine monitoring equipment. 40 lbs is not that much.

 

[AWD PSI 10+ year member]

Trying to work out a sub-woofer solution. Made a mock up of a Rockford Fosgate P3L-S10 to see what kind of room I'd be losing with a similar style setup. I like the idea of a removable box or at least that it's movable. I have a couple sub woofers that I was going to try. One of them requires a 1.5 cu ft ported box, that's bigger than I want to go so I have another on the way that requires a .66 cu ft sealed enclosure. The Rockford mock up worked well because the trunk bar blocks that space from most things anyway. When I did need to fit larger things in my trunk(3 boxes of desk calendars) the box could be moved or put on top of the items. I really want to try and make a fiberglass enclosure. If I like the sub in the smaller sealed box then I think I will go ahead and try and make one.

the bottom of the bar sits 7.25" above the trunk floor

still allows for a pretty usable trunk

the space I'd use for the fg enclosure

 

[CL1CKCLACK 5,000+ posts]

still no sub? look into either dc audio level 2 8 inch sub or a sundown audio sa8. both great subs. will surprise you for being so small and not too bad price wise

 

[AWD PSI 10+ year member]

still no sub? look into either dc audio level 2 8 inch sub or a sundown audio sa8. both great subs. will surprise you for being so small and not too bad price wise

Yeah I know right? It's like blasphemy on this site!

Thanks for the recommendations I will look into them. I'm not dead set on anything at the moment, something with a smaller footprint that can still hit definitely sounds appealing.

 

[AWD PSI 10+ year member]

The polks are pretty well broken in now and the bass has improved noticeably, nothing earth shattering but impressive I think from 4 6.5's, vibrates my side mirrors and that's more than the stockers could do. The rear coaxial speakers put out more than the front components which brings me to my question:

How can I find out what my front components are crossed over at? I'm assuming they are crossed over because the bass output is lower than the rear coax's. Could that be a function of my doors being mostly sealed? The crossover unit only has tweeter attenuation controls, -3, 0,+3 and the specs on my comp set say range is 35Hz-23kHz and the coax specs are almost identical at 35Hz-22kHz but they hit harder. The manual and polk's website offer no insight. The amp gains and xover settings are the same and haven't been set yet. The only thing I've done was add a touch of bass through the eq in the headunit. Maybe it boosts the rear a little bit more? I did the phase/polarity check by fading front to back and left to right. On all speakers bass was weakest on one speaker and improved when faded back to the middle. Fading front to rear, bass was stronger in just the rear as compared to just the front, but was strongest when the fader came back to the middle.

I'm currently reading through the gain setting sticky and speaker FAQ thread so I can start tuning and kind of know what I'm doing. I found this entry in the Speaker FAQs to use as a rough guide. Will this get me close? Suggestions appreciated.

Speaker FAQ

 

subbass (low notes), are usually considered 80hz frequencies and below. - deeep pipe organ, low piano notes, some electric\string bass, techno, the 'rumbly' deep kind of bass, ect.

 

midbass (middle notes on the low end) are usually considered 80~400hz frequencies - kickdrums, cello, electric\string bass, the 'punchy' kind of bass.

 

midrange (upper middle notes) are usually considered 400~5khz frequencies - human male voice, some lower end female voice, drums, guitar, most of the music is here

 

highs\treble\tweet (high high notes on the teeny weeny itsy bitsy strings /end strongbad) are usually considered 5kh~20hz and above - cymbols, guitar on the tiny little high strings, female voices, violin, and all that, the kind of sound that makes your ears hurt, aka - treble.

 

those are just rough numbers, and can be argued to be lower\higher\broader\whatever... im not POSATIVE on the midbass\midrange numbers, but im sure they are close to those numbers.

 

[chillin 10+ year member]

Are the rear speakers in the doors or the deck. If they are using the trunk as a huge box it would probably make them louder.

 

[AWD PSI 10+ year member]

They are in the deck. They do play a little louder so I have the fader put forward one notch for better balance.

 

[AWD PSI 10+ year member]

Ok, I think I jumped the gun a little. I was running the rear coax's about 2 weeks before the front comps and I think the break in happened at different times. I played around with the fading and balance today and all 4 speakers sound like they produce a similar amount of bass. They don't all sound the same i guess due to the different locations in the car but no pair stands out lacking something the other set has. I did notice that the rear coax distort easier than the front comps, thats to be expected as they are spec'd at less than half the rms watt rating. Polk's website has the DB651's rated for 100rms but the manual states 60rms. I amped per the manual before I had seen Polk's site. So to me it looks like the xover crosses the tweeter and handles the attenuating and the woofer gets everything below that.

 

[FJF 10+ year member]

The coaxes are slightly more sensitive. This, coupled with a more efficient install (ie. trunk used as enclosure) allows for more amplitude at lower power levels. This would probably change if you begin to feed a lot more power into the speakers, as the rears would reach the limits of excursion a little sooner, all thing being equal.

 

[chawski 10+ year member]

Have you made any progress on the box yet? just an idea to throw out there to prevent any size requirements due to the strut brace...

Make a box with a 2ish inch tall cutout to fit around the brace, and make it as deep as the distance from the brace to the back of the seat. That way the bar can go through the box, instead of building a box that will only fit under it. thats what I had to do when I built a box for my buddys sti and it worked out really well. Whats nice about it is you can fab up a little hook for each side of the box so you can even use the strut brace to anchor the box in place so it doesnt hit the trunk lid every time you get lead footed from a stop, as im sure happens once in a blue moon in an evo ha

Also, as far as the weight concern... if this were a track car, id say yea, watch every lb you put in the car. Seeing as its probably more of a daily driver with maybe the occasional weekend warrior at the track, I wouldnt even worry about the weight. the gas mileage already stinks on it...100lbs of deadener on a car with 200+ hp isnt gonna slow you down much at all. It might even make the car a bit more enjoyable to drive long distances anyway

 

[AWD PSI 10+ year member]

I have not started the box yet. I just got my sub on thrus so I need to get started. I went with the Polk MM1040DVC. According to Polks website the RMS on the sub wired to 2ohms will match my amp at 2ohms. The manual says different so we shall see. The two pluses were that they claim to use a Neodymium magnet for light weight and the recommended sealed box is only .66 cu ft. I've thought about doing what you suggested with the trunk bar but I hope I don't need to. This is my first box build and I'm hoping to keep it as simple as possible. I tend to use the space under the bar, anything less than about 7.5 in fits under it. I guess my next step is to buy packing peanuts and see what size box I'll be dealing with. If you have any pics of the box you mentioned I'd be interested in seeing it.

I'm trying to let go of the weight thing as it is a daily driver and I'M not a track star, the car does make me look good though. The improvement in sound and overall enjoyment is definitely worth it. I'm adding weight and there is no way around that but if I can I will not add more than necessary. Been toying with changing out my DB's for MM's if I can find them for a decent price, nothing wrong with DB's I'm happy with the performance. They could use another 50w though...

 

[chawski 10+ year member]

ill see if i can snag some pics when im home for thanksgiving, but unfortunately I dont have any with me right now. I would definately go by manufacturers specs for the box size, and if their specs fit under the bar, by all means thats gonna be the simplest build.

Packing peanuts are great for measuring boxes with irregular shapes and curves, like seen in fiberglass work, but if you are building a simple box, a simple LxWxH will give you the internal volume. just make sure to subtract the thickness of the wood if you measure from the outside. Also, If you havnt already, youre gonna want to deaden the trunk significantly. If mitsu could have gotten away with not paining the trunk to save weight, the would have haha. theres nothing back there.

 

[AWD PSI 10+ year member]

Ultimately I want to make a FG enclosure in the side pocket of the trunk. The mock up was of a Rockford enclosure I was thinking of getting. I won't have much time until after the end of the year to work on it. I think I'm going to buy a sealed box for the time being just to get it going while I work on the FG. Haven't really thought about deadening the trunk yet. You are right about the weight, supposedly my model year has a 1lb weight reduction on the trunk itself and the paint on the cars is notoriously thin for supposed weight reduction.

 

[chawski 10+ year member]

Side pocket enclosures are great for the simple reason that they take up the same amount of space, but generally dont take up much, if any useable space. Just make sure its easily removable. I found that out the hard way when i had to change a tail light bulb and the box was formed to some crevices that just didnt let it out. I ended up having to cut an access hole to the back of the tails and re-FG it. definately the most labor intensive light bulb change ever

 

[AWD PSI 10+ year member]

Lol good advice about the taillights, definitely have to watch out for that, thanks!