Ghetto looks, badass sound - part 2 - 12" sub 75W in sealed box, more tunes

[d3dreaper]

I am hopin that it's your camera's mic distortin from the sub and not the sub distorting.....

[uN1Qu3DZ]

obviously it's the cam. otherwise why it would distort only when i put it close to the sub?

i'll try to use a better mike next time.

[ThisIs2009]

just noticed you've got a Sound Blaster AWE64 :-)

[uN1Qu3DZ]

yeah and it's the ISA version! the sats actually run straight off the built-in amp of the soundcard.

[ThisIs2009]

nice, an amp :-) how many watts?

[uN1Qu3DZ]

2.5wpc if i remember right. along with the hardware tone controls it does well for those tesla speakers that i use, they have good sensitivity. as long as you don't ask it to deliver much bass, it gets quite loud.

for this reason the woofer isn't lowpassed, it helps with the midrange and vocals. the sats are going to get a dedicated amp eventually, since the little thing has quite a bit of hiss at high volume, and having part of the midrange thru the woofer loses some of the stereo.

[ThisIs2009]

funny, i read the wikipedia article on your card and it doesn't mention a built-in amp :-) that's still cool tho. what impedance are the speakers, are they ported, sealed, what size drivers/tweeters? what's the thickness of the sub box, how many cubic feet, what's the impedance of the sub, what brand of sub is it, what's the power rating, damn that's alot of Qs!

[uN1Qu3DZ]

it doesn't mention it because in the 90s all cards had built-in amps of 1-4wpc. those flimsy computer speakers came around later, till then the soundcards had amps inside so they could be wired directly to your hifi speakers. oh and it does hardware mixing too unlike today's poor onboards. the awe64 is over 10 years old and built upon 20 year old tech, yet it never skipped a beat. on the other hand i've had lots of headaches with onboards, especially on laptops.

[ThisIs2009]

yeah i'm getting an external creative soundblaster (audigy?) which should be much better than my onboard realtek! i've got 2 new 8" drivers - skytronic 902.426 models. if you looked them up or i linked you to the data sheet, would you be able to tell me if they would produce decent bass in a 0.4 cu ft per chamber sealed box? technics su-z150 amp.

[uN1Qu3DZ]

nope, they need more volume. in 0.4 cu ft you'll get midbass but no house-rattling lows. also, i'd suggest a ported enclosure.

as the manufacturer provides all thiele/small parameters, i can design a box for you if you'd like... oh, and that amp is quite small for those subs. they have rather low sensitivity so they'll need a fair bit of power to go loud. they'd need about 150wpc.

[uN1Qu3DZ]

oh, and you shouldn't seal the two drivers from one another, let them share the same enclosure. put the port in the middle and there you go.

[uN1Qu3DZ]

i'm not sure you're going to like it, but these things call for a large box.

for both drivers in the same box: 2.65 cu.ft (this is internal volume, account thickness of wood), tuned to 31Hz. port 10.2cm in diameter and 27cm in length. port can be mounted anywhere, there is only one rule: make sure there's at least one port diameter (in this case 10.2cm) between the port and any wall or speaker.

with your 30wpc amp you're looking at 100ish dB down to 30Hz. not bad at all.

[ThisIs2009]

if i can get 100dB at 30hz with 2 8s on 60 watts with that box, then that would be amazing! thanky ou so much dude :-) i better start on the build a.s.a.p!

[uN1Qu3DZ]

need any more help, just ask. if you message me your email, i can send the program and sims so you see the graph yourself and adjust if needed.

i only started building based on parameters a few months ago (since i learned to measure the ts params if not available), so far box count=3, but those 3 boxes are the best i ever made. first box, i used a little tv speaker. bass could be heard in the next room, from this tiny 4x2. and it was still able to deliver clean mids and treble. unbelievable.

[uN1Qu3DZ]

2nd set, i adjusted the ports and eq on my crappy set of 8s, and i realized they aren't that crappy. they are hungry of power that i don't have tho. i'll replace them soon anyway, but at least they don't sound like sh*t anymore.

[uN1Qu3DZ]

3rd enclosure is yet to be completed, it's a rebuild of the logitech z-5300 sub for a friends' uncle, mains transformer blew and the only way to open the sub box to take it out was a sledgehammer (it was made of thick CARDBOARD+tons of glue!!!). thus new box had to be made. waiting on new xformer to arrive so i can seal the box, but 1st impression sounds good. will be posted here when it's done.

it's a bandpass but it's far from "one-note bass", i expect it to be better than the original.

[ThisIs2009]

yeah will do! you seem like the only person i've ever talked to on youtube who REALLY knows what they're doing! email is also my MSN addy :-)

[ThisIs2009]

yes please! thanks man :-)

[uN1Qu3DZ]

the teslas are 4 ohm, 6" woofer, 4" tweeter, the sub is 8 ohm, box volume 33 liters, you convert that. sub box is made of osb that's 8mm thick. they are all sealed.

the sub is a "bm", it's basically the better of generic brands. it cost $40. if you have seen my earlier vids i also have 2 8s of the same at home, and they suck. the 15 bm eats lots of power, the 12 is the best balance. peak power rating is 350W, RMS should be somewhere around 100-150. it doesn't break a sweat on my 75W amp.

[ThisIs2009]

cool :-)

[ThisIs2009]

4" tweeters - BIG!

the big box actually looks kinda small for 1.2 cubes!

[coolzeldad]

Big ass crt ftw! :P

and yay bass xD