Which sub to buy.......

[low_bass_makker]

Which is better in both of them.

http://www.alpine-usa.com/en/product...odel=SWR-1542D
http://www.alpine-usa.com/en/product...odel=SWX-1242D

U can read the specs above. Please recommend......

[blueraven316]

Well it totally depends on what your needs are, and what amp you running on.
If you lookin at a lot of Bass with good SPL rating, then SWX is anyday better,

If you looking at midbass, not too much on top and can acomodate 4.5 cubic feet of enclosure space in your car then SWR 15s are okay,

Powerwise SWX will thrash, no doubt, SPL wise SWR wont be far behind as it has more surface area , so more sound pressure, but these 2 subs put you in totally two different categories of DB Drag, Street B and Street C.

I had once hit 131 DB with a single 1000 RMS 10 inch LA sub at DB Drag last year in my zen, so it all depends on what one needs.

[low_bass_makker]

I am gonna run them from mrd-m1005.

Do u recommend x-type ?

[navin]

For the 1005 I would use the 1542 in a huge TL! But I am not too SPL inclined.

[low_bass_makker]

for the spl`s should we go for x-type....

[blueraven316]

Any day the Type X for SPL and you willl be able to set it up properly in Santro boot, 15 inch Type R you cant do that well, Since you are running on 2 MRD1005 s moreover Type X is the choice, If you just had one amp then Type R 15 would have been an option, with two amps like that your subs will blow in 3 to 4 days u pumping.
Enjoy

[low_bass_makker]

what box volume do u recommend ? Sealed or ported ?

[blueraven316]

It depends on what usage, If a lot of top end bass is used (which I think is difficult to bear all the time) then Ported Boxes is the thing, if one likes midbass , not too loud volumes and tight bass, then sealed (sealed does not mean completely sealed, where you cant see the sub, that setup humms a lot and is not suitable for such powerful subs), If you are lookin at SPL compettions later, then a Big Double port box with Wide and Short port length is good, but that will not give daily use clarity, the manuals will have the best settings, but for a Type X, personally i feel 1.75 Cubic Feet per sub , ported should be good, I could be wrong, chk the manuals, it can be 2 Cubic feet also.

[Bass&Trouble]

If a lot of top end bass is used (which I think is difficult to bear all the time) then Ported Boxes is the thing, if one likes midbass , not too loud volumes and tight bass, then sealed (sealed does not mean completely sealed, where you cant see the sub, that setup humms a lot and is not suitable for such powerful subs),

People tell me I'm getting older, but try as I might I cannot understand the reasoning in the following.

Top-end bass from ported boxes that you cannot bear all the time? Mid-bass from subs 'a la' sealed box?? If sealed does not mean completely sealed, then what does sealed mean??? If you seal a sub inside a box without the driver visible, you wont hear the sub. If you make a bandpass enclosure it ain't called sealed. The sealed enclosures I know of are...well, sealed!?

If you are lookin at SPL compettions later, then a Big Double port box with Wide and Short port length is good, but that will not give daily use clarity, the manuals will have the best settings,

So a double port box is different in principle from a single port box and ports can be made wide and short for that extra bit of bass?

but for a Type X, personally i feel 1.75 Cubic Feet per sub , ported should be good, I could be wrong, chk the manuals, it can be 2 Cubic feet also.

Ok, what port sizes? And would 1.75 be better or 2 cu.ft for a spl setup? Please also give box dimensions based on the volume selected. I'm sure LBM wants to blow away a lot of people he doesn't like here with his bass (hee hee!), so let's have a spl design.

[low_bass_makker]

True man wanna flew some people here away with the bass. Seriously I think u have some indepth knowlegde about electrical stuff. Would like to meet u personally If i ever come down to bombay...

[toy car]

hey mann go for the Alpine x-type 12 inches

[blueraven316]

Double port boxes indeed produce more bass than single port ones with same Box Dimensions, but clarity is compromised,
The LA Manual suggested for Better SPL ratings a Double port box , so, We tested LA and Rockford Subs with Double and Single port boxes with same dimensions a night before the Drag with Zareer's SPL Meter ( The one used for DB Drag next day made by term pro labs ) The double port boxes clocked about 1.5 Db higher, We talk after we have done it, that is what i believe in, Knowledge comes to some Via Books, to some via experience and reading. There is always a principle behind any Physics, all this SPL Blah Blah is based on principles, but there is something called practical application, for Ex: A lot of people know how to bend a bike and know about racing line etc, but there is just one Valentino Rossi, he might not be the best engineer, but he wins.

Now, @ LBM, send me your car's boot's max inside dimensions , width, height upto where a box can be acomodated, depth on top and bottom,
Since your car has a small boot, I think its better to mount your amps under the seat for a day During DB Drag, so u have 1.5 inches extra space for the Box. Send me the Dimensions and what amp you are gonna run what subs , and I will send you dimensions with Port length and width.

[navin]

Blue Raven,

Port dimensions (Av and Lv) are usually calculated based on Fb, F3, & Vb. For any specific tuning you can get ports of different dia (2", 3" 4"...) and the larger the port the longer it needs to be for a specific tuning. A larger port produces less chuffing and hence it is best to use the largest dia port posible.

Given that large dia ports are also long often they dont fit into a cabinet so a large dia port can be "broken up" into 2 or more smaller dia ports as long as Av remains the same. For example a 3" dia port has an area of 7 in2 and a 4.25" dia port has an area of 14in2 so 2 3" dia ports of shorter lenght can be substituted for a long 4.25" dia port.

Now this is a simplestic explanation. For more detail google will help or check out this pdf and diyaudio.com

http://www.interdomain.net.au/~bodzio/PORTS.pdf

http://www.diyaudio.com/forums/showt...899&highlight=

http://www.diyaudio.com/forums/showt...944&highlight=

[Bass&Trouble]

Originally Posted by navin

Port dimensions (Av and Lv) are usually calculated based on Fb, F3, & Vb. For any specific tuning you can get ports of different dia (2", 3" 4"...) and the larger the port the longer it needs to be for a specific tuning. A larger port produces less chuffing and hence it is best to use the largest dia port posible.

Given that large dia ports are also long often they dont fit into a cabinet so a large dia port can be "broken up" into 2 or more smaller dia ports as long as Av remains the same. For example a 3" dia port has an area of 7 in2 and a 4.25" dia port has an area of 14in2 so 2 3" dia ports of shorter lenght can be substituted for a long 4.25" dia port.

Blue Raven certainly doesn't subscribe to your logic about ports. After all he's measured the difference with a Term Labs setup and knows that he can get a few db louder with a few more ports, but at the expense of clarity. There ought to be a paper from him on this, interesting new addition to the AES archives.

[navin]

Originally Posted by Bass&Trouble

..There ought to be a paper from him on this, interesting new addition to the AES archives.

Hey I came here to learn as much as to share the litttle I know and B&T by know you know that my knowledge it very limited. After all I do not, and have never worked in the audio industry. I never expected to know as much as the Pros.

1. What little I know is dated
2. my "logic" can be flawed

Blue Raven please enlighten. please please please. The internet is no place to hide knowledge.