Beginner guy with beginner questions

[SnowDrifter]

There are a few things that I don't understand when it comes to car audio

1. I know there are reccomended cu.ft amounts of box volume for a subwoofer. What happens if I get a box on the smaller end of the reccomendations? What about on the higher end? Are there any pros / cons to each?

2. I kind of know what a sub box port does... But what is to stop me from tuning to say... 20 hz? How about 50 hz? I know that most people tune in the range of 30-35 hz, and that you get loudness by tuning high, and sq by tuning low... But why not tune REALLY low so my sub can hit any and all notes in a given song?

3. Screws vs nails for a subwoofer box? and how do you guys get perfect 90 degree angles? I am having trouble getting it to glue, and stay at 90 degrees while the glue sets...

4. Is sound deadening on the inside of the box worth it? And if so, what is the best to use? I have heard of folks using rubberized spray.

5. Hi everybody!

[Robert8252]

Hmmmm. Good questions when you're starting

1) recommended size from a Manu. Pretty much means that their sub will perform well in that enclosure and shouldn't have issues of the sub being damaged as long as you're in their specs.

2. Tuning. By tuning to say 20hz you would lose a lot of higher end output. By tuning to say 32 you still get good output from 30-45hz without a lot of loss between but a box still shines at it's tuning frequency of music.

3. Glue. Only glue. Glue makes your box joints stronger there then the wood itself.

4. Never sound deaden the inside of the box. Sound deaden all metal panels of your car though for best results. Any metal vibrating is a loss of sound pressure turned into rattle.

5. Hola mi amigo welcome to the SMD forums where you can learn much from searching around for a few years to read it all

[Alex K]

I use glue and a nail gun with inch long nails. They don't split the wood like a screw, but give the extra support. Also, I just put down the first wall piece, then do the next one with something sturdy and with a 90* angle and fasten em down. With 2 pieces attached, there's no way it wouldn't dry straigiht. It's worked everytime for me.

[irpirate]

ive only built two boxes but lining up the boxes predrilling, glueing, then screwing has worked great for me. the screws clamps the wood together while the glue dries. dont really hafta worry about getting 90 degrees or not being to do anything else while waiting for it to dry

[SnowDrifter]

Hmmmm. Good questions when you're starting

1) recommended size from a Manu. Pretty much means that their sub will perform well in that enclosure and shouldn't have issues of the sub being damaged as long as you're in their specs.

2. Tuning. By tuning to say 20hz you would lose a lot of higher end output. By tuning to say 32 you still get good output from 30-45hz without a lot of loss between but a box still shines at it's tuning frequency of music.

3. Glue. Only glue. Glue makes your box joints stronger there then the wood itself.

4. Never sound deaden the inside of the box. Sound deaden all metal panels of your car though for best results. Any metal vibrating is a loss of sound pressure turned into rattle.

5. Hola mi amigo welcome to the SMD forums where you can learn much from searching around for a few years to read it all

For the reccomended box size.... Then would I be fine going with the minimum box size for space? Or would I be sacraficing / gaining anything?

And for box tuning, if I tune to 20, then I would lose my bass response at 60hz for example?

5. Thanks!

[P4killer_]

Well as far as airspace, as long as it within thier guidelines, you are fine. Really you can be outside of the reccomended sizes and still be fine, it just wont be optimal. Say you have 2 12's that need 4 cubes ported for the pair, but you can only squeeze 3.5 after port and woofer displacement. Youll be fine.

As for losses/gains im not perfectly sure, but I do know that a smaller box lets you run more power safely, so if your going to run over ur rms it can ok to an extent. a smaller box is less efficient than a bigger box meaning it will take more power to get louder, where as a bigger box can get louder with less power again there are limits. Running too small a box, will choke the sub, not allowing it to move as much air as it could. Case in point 4 12's in 5 cubes which is choking them, will likely be in the same ball park if not less than 2 good 12's in thier proper airspace, because they have room to breath. Running a bigger box has it downfalls, the sub has less control. So playing a super low note say 20hz at max volume can cause the sub to bottom out, damage itself, simply bigger boxes mean you cant push it as much especially at harsh freq like 20hz without risking ur subs.

Anyway, 20hz is a pretty low tuning, 20hz is the limit of what you can hear anyway, if you wanna tune low shoot for 30hz at the lowest, but as someone has already said tuning to 35hz, you will still be able to grab the lows nicely.

Feel free to correct me if ive slipped on anything

[bassl0va]

For the reccomended box size.... Then would I be fine going with the minimum box size for space? Or would I be sacraficing / gaining anything?

And for box tuning, if I tune to 20, then I would lose my bass response at 60hz for example?

5. Thanks!

Well, it will be quieter at 60hz so yes. If you have a look on sites like hometheatershack.com you will see that almost everyone tunes to below 20hz, some tune to 14hz (I think I even saw 11hz once ) But that's for movies where you have explosions and rumbles. In a car there almost no point in tuning that low.

EDIT: oh and yes, bigger boxes are more efficient but you can't push as much power to the sub as you can with a smaller box (which is less efficient) but I wouldn't worry about that at the moment.

Well as far as airspace, as long as it within thier guidelines, you are fine. Really you can be outside of the reccomended sizes and still be fine, it just wont be optimal. Say you have 2 12's that need 4 cubes ported for the pair, but you can only squeeze 3.5 after port and woofer displacement. Youll be fine.

As for losses/gains im not perfectly sure, but I do know that a smaller box lets you run more power safely, so if your going to run over ur rms it can ok to an extent. a smaller box is less efficient than a bigger box meaning it will take more power to get louder, where as a bigger box can get louder with less power again there are limits. Running too small a box, will choke the sub, not allowing it to move as much air as it could. Case in point 4 12's in 5 cubes which is choking them, will likely be in the same ball park if not less than 2 good 12's in thier proper airspace, because they have room to breath. Running a bigger box has it downfalls, the sub has less control. So playing a super low note say 20hz at max volume can cause the sub to bottom out, damage itself, simply bigger boxes mean you cant push it as much especially at harsh freq like 20hz without risking ur subs.

Anyway, 20hz is a pretty low tuning, 20hz is the limit of what you can hear anyway, if you wanna tune low shoot for 30hz at the lowest, but as someone has already said tuning to 35hz, you will still be able to grab the lows nicely.

Feel free to correct me if ive slipped on anything

Lol, yeah, slipped on the 'post' button

Triple post FTMFL!

Edited November 2, 2010 by bassl0va

[moetpoppin]

hahahahha

the rare trippple post fail!

[SnowDrifter]

Thanks everybody for the replies!

Just one more question: I have heard mixed things about caps... Do they help / hurt / do anything? I have also heard that if you have a quality battery bank, then you don't need a capacitor; Which brings me to my next question... As a rough rule of thumb, how much battery do I need for X wattage of an amplifier?

[ChevyBoy95]

Thanks everybody for the replies!

Just one more question: I have heard mixed things about caps... Do they help / hurt / do anything? I have also heard that if you have a quality battery bank, then you don't need a capacitor; Which brings me to my next question... As a rough rule of thumb, how much battery do I need for X wattage of an amplifier?

caps are almost useless. I have used them before and they did almost nothing. If you ever need an electrical upgrade you might as well do it right by either upgrading you battery(to like XS Power, Kinetik, Shurukin, etc) or upgrade your alternator to a high output one.

If you going to run 500 watts rms you don't need electrical upgrades, I didn't do anything until about 1800 rms because that is when my voltage would drop. If it's under ~1300rms you don't really need electrical upgrades but if you go more than that look into it.