box design for alpair10's

[Curt96olds]

Im gonna be purchasing 2 Markaudio Alpair-10 Grey 6" Full Range Gen 2: Madisound Speaker Store one for each side of my computer desk, now i have experience with box building and designing when it comes to subwoofers (mainly car audio) but this will be my first box of this kind.

with that in mind i would like to keep it simple, just a simple ported box, and i have 2" aeroports already so i would like to utilize them.

basically what i need to know is how big should the box be and what should i tune the port to? the speakers will be high passed at 50hz with a 12db/octave slope but will be playing the full frequency range from there on up.

i dont understand litres and stuff so if possible could i get it in fraction of cubic feet? as in like .2 cubic feet or .5 cubic feet.

thanks!

[larryldspkr]

Plugging the 10.2 specs into bass box pro gives an internal dimension box of 15.5h X 9.5w X 6d in inches. Port size of 1.5 inside X 5 long, line all sides with damping!

Larry

[Curt96olds]

thanks larry, but is there anyway i can just get cubic feet and tuning measurements? those dimensions wont really work for where im putting them, i have a program i use for plugging in dimensions and a port area to find tuning.

basically im just looking for "rule of thumb" measurements, like a generalized tuning that most people use for these kinds of speakers and such, and considering it is my first box im most likely gonna make another one, its not like its expensive to buy the wood for it.

[larryldspkr]

This box is .5 cubic feet tuned to 38.5hz! Juggle the dims,keeping the same volume and tuning. I think this would be a minimum volume for this driver!

Enjoy!

[Curt96olds]

now im not questioning your reasoning on the 38hz tuning, im just trying to learn, but i thought i would be tuning it alot higher honestly, like around 70-80hz, since it wont be playing anything lower then 50hz anyway, why would i tune so low? again not arguing, just trying to learn, also, with the 38hz tuning, it would till play up to 20khz no problem?

[larryldspkr]

Tuning frequency is usually around Fs, this will damp the cone @ fs and give a reasonably smooth SPL! Tuning an octave above as you suggest would give a large boomy peak around that frequency! With the set-up I suggested you probably would not need a sub. I am using this driver in a 14 X 20 ft. room with a 5 watt KT88 se tube amp, the bass goes low and is VERY tunefull! Not wishing for a sub here!

Cheers

[Curt96olds]

thanks for your explanation, that explains it. but i am still gonna need a subwoofer, i listen to alot of really heavy music, like the devil wears prada, job for a cowboy, bands like those, and alot of it digs way down in the frequency range, and i also listen to alot of bass heavy music like hip hop and dubstep which of course also digs way down in the frequency range.

[larryldspkr]

You are right...I don't listen to that kind of electronic bass, subs will be required!

[GM]

Based on your stated needs, a lightly damped ~0.16 ft^3 net sealed alignment XO'd around 80 Hz is a much better solution to a vented one.

If the 50 Hz/2nd order XO is a given, then a vent tuning at least 50*0.707 = ~35.4 Hz is theoretically called for, requiring ~1.05 ft^3 net and maybe some EQ to flatten it all out in-room, potentially not having enough power handling in the octave above Fb/Fs.

GM

[Curt96olds]

the 50hz crossover isnt set, i was gonna buy some of those rca crossovers that partsexpress sells,http://www.parts-express.com/pe/show...number=266-270 and use those, i just figured 50hz would be a good frequency to start rolling off, and leave the rest to the sub.

i already cut out the wood for the box, but the port is still negotiable, I.E what size and length. the box is 14x8x12 outside dimensions, half inch wood.

if i do a 1.5 inch round port thats 5 inches long i will end up with a box thats .55cubic feet and is tuned to 37.84hz