Help again...

Grimster74

Finally, after two weeks I finally installed my new polk speakers and amps. Well, as one would figure just not pleased with the low end which I knew would happen. So after much thought I've decided to add two 8" subs. The amp I will be using to drive the subs is a Alpine MRP-M350 monoblock amplifier. The amp is rated to deliver 350x1 at a 2 ohm load so I will be buying 4 ohm subs. The question I have today is this. Do I purchase 2 Polk MM2084 8" subs or do I purchase 2 JL Audio 8Wo4's. What would the benefits be from one to the other. They are both in the same price range, just been hearing alot of negatives about Polk's subs.

exalted512

are you saying low end as in bass in general or low end as the low end of a sub's frequencies, if the latter, then an 8 isnt going to solve your problem
but other than that, JL sucks...go with Polk
-Cody

Grimster74

Not looking for really low bass, don't have the room to add anything larger than 8's. I'm just looking for a little more rear filling bass, something with a little more PUNCH other than 5x7's which are currently installed in the rear doors.

MacLeod

Originally posted by exalted512
JL sucks...go with Polk
-Cody

Ah yes, detailed, productive and always informative.

The MM 2084 is a lot better than the 8W0. Those are JL's entry level subs and arent all that spectacular not to mention they will not handle the same power as the MM.

The 8W3's would be a more direct comparison for the MM and I would still go with the Polk as it will sound just as good for less.

Joelsbass

oh my... the world just ended... mac made a case against JL...

lol


nice HT btw Grim

exalted512

Originally posted by Grimster74
They are both in the same price range

Originally posted by MacLeod
The MM 2084 is a lot better than the 8W0.

you mean...no it couldnt be that the subs are...and i repeat "a lot better than the 8w0" but theyre in the same price range????
unbelieveable!;)
-Cody

MacLeod

Oh for the love of Pete!

I never once said JL is the G mack daddy (aint I hip?:D) of car audio!

I do think they are excellent gear but not necessarily the best.

I do think the W6 is the best sounding sub that Ive heard and that the XR components are some of the best on the market. Other than that they fall from grace a little.

I like Xtant, Orion and Alpine V12 amps better than JL's and Crossfire and MTX as much. I dont like the TR and VR speakers much at all. The W0 subs are decent and W3's are pretty good but arent spectacular by any means.

And yes, the W7 is too damn expensive.

There! I said it!! Are you happy now?!?

exalted512

Originally posted by MacLeod
Oh for the love of Pete!

whos pete?
is there something we should know big mac?
and yes...as a matter of fact i am happy...this is the first sign of progress ive seen out of you yet
-Cody

MacLeod

Progress?

Youre missing my point. This is nothing different then what Ive always said. My opinion has remained consistant. You say JL sucks. I say they dont. I never said they were the best and Ive bitched about them a bunch. I just come to their defense when you start trashing them as if theyre Pyle or Kraco.

And no, there is nothing you should know.....you sexy beast you.

exalted512

no....were making progress:)
one day, you too will know the evil ways of JL and will see the light of all which is good and anti-JL young Jedi knight
-Cody

PS Hope you like my new signature

Grimster74

Okay, so I'm guessing everyone is for Polk.:D

Grimster74

I know everyone has said to go with the Polk Audio subs, BUT, what if I stepped up to the 8W3v2-D2 JL subwoofers. I could run the voice coils in series to maintain a 2 ohm load. Which would sound better and/or play louder. I'm not expected extreme SPL levels, just want something to play accurately with tight bass.

exalted512

if you want to, then just get the 4 ohm models and wire them in parallel...voila, 2 ohm load
-Cody

Grimster74

Are you talking about the 8W0-4's, if so, isn't that what MacLeod told me to stay away from beings they are JL's entry level subs, or are you just saying get 4 ohm subs in general. Not trying to be a pain in the a$$, just trying to get the best subs my money can buy with no more than 4-1/2" top mounting depth.

exalted512

ill never recommend JL, i was talking about the momos:D
if you have two mm2184s, then you can wire them in parallel to achieve a 2 ohm load
-Cody

Grimster74

Okay, I've ordered the Polk subs. Here is my next question. Can someone tell me the formula for calculating air space.

Systems

Why doesn't anyone recommend Pyramid subs...

exalted512

using internal dimensions
its length x width x height divided by 1728 if your dimensions are inches...the answer to (lwh)/1728=cubic FEET
-Cody

MacLeod

Originally posted by Tymm
Why doesn't anyone recommend Pyramid subs...

The same reason we dont recommend Kraco, Sparkomatic, Audiovox, Rampage, Jensen......notice a theme?

exalted512

Originally posted by MacLeod
The same reason we dont recommend Kraco, Sparkomatic, Audiovox, Rampage, Jensen......notice a theme?

you forgot JL;)

MacLeod

....one of these days....

Grimster74

Okay, I've finished designing my new sub box in AutoCAD. After taking internal measurements and calculating the air space I will be putting two Polk Momo 2084's, 8" in approximately 0.65 cu.ft. I'm assuming this will be okay considering a single 8 calls for 0.35 cu.ft. I will be adding polyfill to the box to trick the 8's into thinking the box is actually larger than it really is. Haven't decided yet if I should build two seperate enclosures or just one single enclosure for the both. I will be building the box out of 1/2" MDF which is a "MUST", and I repeat, "A MUST" due to the lack of room behind the rear seats. Does anyone see any problems with what I've provided so far.

exalted512

you can do it with 1/2" MDF...but if thats a MUST...then you MUST put a SHITLOAD of bracing
if your box flexes HALF THE WIDTH OF YOUR FINGERNAIL, it can cause DRASTIC effects...im talking clearly audible effects
another option is 1/2" maple birch plywood, its lighter and stronger than MDF, but it is more expensive
and i would try to go with dual chambers instead of 1 big one, it usually works out better
-Cody

Grimster74

Where exactly do you find maple birch plywood. Is it maple and birch plywood laminated together?

exalted512

excuse me, birch ply....i do that a lot...dunno why
but its grade a, furniture grade, birch ply...you can find it at home depot, etc
-Cody

Grimster74

Okay, built my box yesterday. Polk 8's WILL NOT go behind the rear seats of my toyota tacoma. Could not find 1/2" MDF anywhere in town so I ended up going with 5/8" MDF. Guess what, they just won't fit. The box will fit fine, but the subs are pressed right against the rear seats with no room for the subs to travel. Do you guys have any suggestions. I've even gone as far as thinking about placing 6-1/2" Bazookas behind the rear seats. Any suggestions would be greatly appreciated.

exalted512

put grilles on them?
-Cody

MacLeod

Well this is the problem with trucks. They have very little room for anything. With trucks, its gonna be a lot easier if you go with a single sub.

About the only thing I can think of is that you should just rebuild the box. If its too thick and pressing the sub against the seat then you should make it thinner and taller. This should help. Also, you can shave a tiny bit off the box and be ok. Knocking it down from .65 to .63 shouldnt affect SQ much and it will give you a little more room.

Grimster74

Okay, I think I've figured it out. After posting my last post yesterday I re-designed my thinking. What I did was I built the top, sides and the center that seperates the two chambers. I built a temporary front and mouted the sub and guess what, it fits. So what I'm going to do know is fiberglass the bottom and the back of the box which will leave me plenty of room behind the magnet, somewhere around 1/4". My question know is, where do I find fiberglass resin and the actual fiberglass and roughly how think or how many layers of fiberglass would you recommend. I think I'm also going to route out the mounting hole where the sub goes to recess the subs flush with the front of the box along with reinforcing the underside where I route it out with fiberglass also. Let me know what you think.

Grimster74

Alright, I just returned from Lowes, I've purchased everything I need to fiberglass my box for my Toyota Tacoma. The next question I have is how many layers of fiberglass should I be safe with applying as far a durability goes. The top, sides, center and the front of the box are going to be constructed of 5/8" MDF. The rear wall and the bottom of the box will be fiberglass. After redesigning the box I should have 0.375 cu.ft. +/- of air space per sub.

neomagus00

more is better, clearly, but it depends upon how big the sheets of 'glass are. if they're gonna be big, flat expanses, it'll need to be pretty damn thick (i dunno how many layers, 7-10 i'd guess). if it's a small area and it's all twisty-turny then you can get away with less, maybe 5?