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Discussion Starter · #1 · (Edited)
Well I finally got around to doing my new system. It's not complete just yet but this is what I have so far:

(2) 15" DC sound labs Level 4 XL's
(2) Audiopipe ap 18001's strapped
Audiopipe ap 2004
Audiopipe ap 3002
(4) Selenium 6W4P 6" Woofer's
(2) Selenium 8W4P 8" Woofer's
(2) Dayton RS225S-8 8" Woofer's
(4) Crescendo audio Supertweets

The sub's are in a 4th order bandpass pushing up through my rear deck. I believe it's 1.5 ft3 each sealed and just under 9 ft3 ported.



 

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Discussion Starter · #2 · (Edited)








 

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Discussion Starter · #3 · (Edited)




The back deck almost ready to lay fiberglass.

 

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Discussion Starter · #4 · (Edited)
I finally got the speakers installed and wired in the back deck.

I don't know if I like the look of the Seleniums in the back. I might change them out, not sure.

By the way, the pics don't do it justice...







 

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Discussion Starter · #5 ·
I am planning on having the rear deck and the trunk done later this month. (at least that's the plan)

In the pics I have the Selenium 8's in the doors but I already ordered the dayton 8's to replace them. The Seleniums I'm going to put in the back deck along with two more of the Crescendo supertweets.
 

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Looks bad ass man. Doing the same thing with 2 18" LVL 5's. What is your ported side tuned to? and what kind of range are you getting from it?
 

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ya dudes be trying to shake a neighborhood lol just the block or 2 isnt enough? good work though. show car or DD?
 

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Discussion Starter · #9 · (Edited)
Looks bad ass man. Doing the same thing with 2 18" LVL 5's. What is your ported side tuned to? and what kind of range are you getting from it?
I can't remember what the port is tuned to. But my car peaks at 34hz on the dash.
 

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Discussion Starter · #10 ·
ya dudes be trying to shake a neighborhood lol just the block or 2 isnt enough? good work though. show car or DD?
LOL right. No I wish it could be a show car, still needs ALOT more work. This is my DD.
 

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Cool, but all that work and power and you are using plywood?

You know they have lightweight MDF if you wanted to save on weight...?

It's more than double the price than regular MDF, but it looks as if money is no object here. I mean do it right once right?


Doors look a little too busy and bulky for me, but if it's sound you're going after over looks, you got it.

Can't wait to see it finished. :)
 

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In my opinon Plywood> MDF. Plywood is way more rigid then MDF. But I do use both.

Got below info from-
http://www.talkaudio.co.uk/index.php?option=com_content&task=view&id=91&itemid=26

Mechanical properties:-
In laymen’s terms, strength is an indication of how much load a material will withstand before failure and stiffness is how much the material will flex, or deform, when subjected to a given load.

We are not really interested in the ultimate strength of our sub boxes as they seldom fail, so the material strength is of little use. However, we are interested in how much a box will flex. Therefore, we will concentrate on the stiffness of sub box materials.

Eb = Modulus of elasticity in bending.
Eb describes how stiff a material is under bending. The higher the number, the stiffer the material is and the less it will flex. It allows us to easily compare the stiffness of different materials.

The following properties are all based on 18mm sheet materials:

Birch faced ply:-
Eb = 2700 N/mm^2 perpendicular to grain
4600 N/mm^2 parallel to grain
Density = 11.6 kg/m^2

Birch ply:-
Eb = 3400 N/mm^2 perpendicular to grain
4600 N/mm^2 parallel to grain
Density = 12.4 kg/m^2

MDF:-
Eb = 2200 N/mm^2
Density = 10.8 kg/m^2

It can be seen from the above, that the plywood properties are directional depending on the orientation of the grain. For the purposes of this analysis, we can assume the stiffest properties as sub box panels are generally supported on all four edges. MDF is a homgeneous material and the mechanical properties are identical in any direction.

Comparing the Eb values given above it can be seen that the birch based plywood is over twice as stiff as the MDF. Therefore, if two identically sized sub boxes were fabricated, one from 18mm MDF and the other from 18mm birch ply, the MDF box would flex twice as much as the birch ply box.

That’s quite an improvement from simply using a different material for your enclosure.
 

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Interesting...always thought the old rule of "use MDF" was still good, not to say I believe anything you just typed.

Almost any wood could be stronger than MDF (I'm sure the numbers are out there), because MDF is basically just glued saw dust.

MDF definitely looks better and works well. I wonder, if other woods are cheaper and work just as well, why haven't speaker box manufacturers produced their product with them?
 

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Interesting...always thought the old rule of "use MDF" was still good, not to say I believe anything you just typed.

Almost any wood could be stronger than MDF (I'm sure the numbers are out there), because MDF is basically just glued saw dust.

MDF definitely looks better and works well. I wonder, if other woods are cheaper and work just as well, why haven't speaker box manufacturers produced their product with them?

I pulled all that info if off that link. I really could careless if you believe me or not, Just trying to put the info out there. Never said MDF is a bad material it is cheap and works just fine in most set-ups. You want your box to be as rigid as possible so it doesn't resonate and that is why I go with Baltic birch for high power systems.
 

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Discussion Starter · #15 · (Edited)
You beat me to it Kapone. I used Birch because it is stronger and lighter than MDF. But the down side is that it cost almost twice as much. Hands down Birch is the way to go if you are doing a BIG system. For smaller systems go with MDF.

Like I said the trunk is not finished. You will not see any of the wood by the time I'm done.
 

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Discussion Starter · #16 ·
Interesting...always thought the old rule of "use MDF" was still good, not to say I believe anything you just typed.

Almost any wood could be stronger than MDF (I'm sure the numbers are out there), because MDF is basically just glued saw dust.

MDF definitely looks better and works well. I wonder, if other woods are cheaper and work just as well, why haven't speaker box manufacturers produced their product with them?
Birch is the only plywood (if I remember correctly) that is better than MDF. All the other plywood is too porous. Trust me, I didn't cut corners when I decided to use Birch. Infact if wanted to go cheap I would have just used MDF instead.
 

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Discussion Starter · #17 ·
Well I did some more testing on my system tonight. My peak frequency on the dash is 34hz. Damn the ish is lowwwwwww!! But the down side is that it's not that good to compete with.

But my goal with the system is to beat down looooooowwww more than it is to compete. I took a couple of pics of the results tonight. By the way both pics are at 34hz measured on the NEW Term Lab.

Car sealed on a burp:



Driver door open on a burp:

 

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Well I did some more testing on my system tonight. My peak frequency on the dash is 34hz. Damn the ish is lowwwwwww!! But the down side is that it's not that good to compete with.

But my goal with the system is to beat down looooooowwww more than it is to compete. I took a couple of pics of the results tonight. By the way both pics are at 34hz measured on the NEW Term Lab.

Car sealed on a burp:



Driver door open on a burp:

Ay man a legal 145.7db @ 35hz is a great score. Alot of people can't get that score at 50hz. And if you could find out what it is tuned to or hook me up with port specs I would really appreciate it, I love the lows too. And getting the tuning would save me alot of trial and error.
 

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Birch is the only plywood (if I remember correctly) that is better than MDF. All the other plywood is too porous. Trust me, I didn't cut corners when I decided to use Birch. Infact if wanted to go cheap I would have just used MDF instead.

I think you are right as long as it is void free and atleast 7 ply.
 

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Discussion Starter · #20 · (Edited)
Ay man a legal 145.7db @ 35hz is a great score. Alot of people can't get that score at 50hz. And if you could find out what it is tuned to or hook me up with port specs I would really appreciate it, I love the lows too. And getting the tuning would save me alot of trial and error.
Thanks.

I don't have any of the specs but if you want me to take measurements of the port just let me know. By the way, are you going to do the two 18"s in a forth order? If so how the hell are you going to have enough room?????. I barely had enough room to do my two 15"s with all the amps and batts in the trunk?

By the way, I plan on taking a video of the car soon. This bish is flexing pretty good.
 
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