help with 4th order for 16 12's

[irpirate]

i have 16 infinity 1262w's d4's running off a saz 3500 @.5. i built a ported clamshell for it but it isn't performing like i hoped it would.

gonna be building a 4th order in january but wanna get the design verified. (note: initial design was done by 2000lade, i just tweaked with it). never designed or built a 4th order before.

outer dimensions are 59.5 depth. 33 height. 37.5 width

16 subs. 8 per sealed side.

qts - .46

Vas - 2.83 ft^3

Fs - 25

the sealed area will be 7.93871 per 8 subs. so Vr - 15.87742 cubic feet - sub displacement accounted for

ported area. Vf - 17.88276 cubic feet.

double baffled loading wall. single baffle will give me 18.4

i modeled it up on winisd. port is 19x19. tuned to 45.5. sub and port displacement accounted for.

45.5 hz tuning. all displacement accounted for.

note:2000lade suggested a 19.5x19.5 ported 3 inches long. said it would tune to 45. kinda confused on why he said that. hes the guy with 48 sa10's in his truck. he also said that 2:1 ported:sealed was what he would shoot for but i just don't have the space for that in my tiny *** 4runner. so its looking like 1:1.

thanks all!!

 

[akheathen]

oh, wow....... i think you are only getting little more than 80 watts per sub, so i would try dropping the subsonic even more, or set the amp flat (lpf only) and see what it does. so, they really don't stand a chance of over-excursion. only thing it could hurt is dragging down in the lows, imo..... if you think 30 shakes ****, just wait 'till you get in the 20's (82.5wrms per sub based on series voice-coils per sub @8ohm, then all paralleled)

 

[irpirate]

I just realized I actually don't know what the subsonic should be set to on a 4th order. It made a huge difference already just changing it to around 30-31. the modeling on the first page on winisd should be about right. Lower F3 should be around 27 or so. should it be set at 27? maybe a lil bit lower? it does already plays everything on the screwed songs, especially after the first change. and also how did you get the 82.5 watts per sub.

 

[akheathen]

with the subs individually wired to 8ohm, you pretty much divide 1300 by 16..... either way you look at it, that's as much as each gets. if you change the configuration, the amp puts out differently from if you end up with different ohm load, or one way may balance the power better...i don't remember what the box is tuned to, but there are 2 scenarios. it can get peaky around there, so you tune for sq. and the other, is that output will drop off and the drivers will just move more freely. i would start without a lpf or bass boost/eq and see what it does. start at lower levels and watch excursion to make sure it doesn't get bad near peak, then listen to it and see what the box tuning looks like. you may be supprised, and missing out on tremendous output below 30. to give you an exaple, i tuned a box to 36, but it peaks real hard below that and shakes all the way to the bassment violently.

 

[2000LaDe]

just put the subsonic down to like 20-25hz. and put your low pass to around 60ish hz. should be fine that way. i have my subsonic all the way down

 

[80INCHES]

agree..subsonic filter all the way down.....thats how i have it..and i have mt lpf all the way down as well..i love me lows //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

80

 

[irpirate]

thanks guys! will try that in a bit here.

 

[Vossy]

I have my subsonic low as possible

Put lpf at 65imo

 

[THATpurpleKUSH]

Shouldn't subsonics be set around f3? My f3 is 31hz and I have a nonadjustable 28hz subsonic but it doesnt really seem to hide an low notes when its on.

OP- what were the final volumes and tuning of the box?

 

[THATpurpleKUSH]

internet fail

double post

 

[irpirate]

the final volumes are roughly 16:16. probably a bit under 16 on the sealed side. tuned to 45.

was driving out to grab food and decided to stop and make a quick vid. subsonic was set around 20 based on suggestions from another forum. forgot to rev the engine again T_T first song is money man, second is hypnotize. thanks to decaf for both //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif



I say it's ridiculous at the port because when I occasionally like to stick my head into it =D

 

[galacticmonkey]

With such a small amount of power per sub and a 4th order with a 1:1 ratio, you would be fine turning the LPF all the day down, or completely off if you can. Just the pressure on the front and rear of the cone from all 15 other speakers is enough to keep excursion in check.

 

[irpirate]

thanks for the tip. the subs are rated 300 rms each though.

and eff you for the comment //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[irpirate]

update time! - emailed infinity about power handling on the subs, was told they were underrated, said they would be fine on 400 per. gonna be buying another 3500 soon. I finally got home last night at 11. negative 7 degrees, no idea what the windchill was. garage is full of sub boxes to fit my car in so i worked outside and froze my *** off; 8-9 hours of work.

6.5"s think a several other people here on smd ordered a case or two of these off ebay. thanks hank for the find. not sure if i wanted to use 16 of these or 4 phoenix gold 6x9s and 4 3.5" bullet tweeters. ended up deciding on the 16 6.5s just because mass amounts of speakers look sexy. powered by a kicker zx 850.4

more bafflz. i'm getting pretty **** good at cutting holes with jig saws but i got kind of careless, ended up not mattering.

decided to go with black carpet for finish just because i've never really done anything other than truckbed liner. figured carpet would be fairly simple and forgiving. i suppose availability played a big factor too. ty walmart.

it's not completely sealed, there's lil cracks and what not that i missed. for some reason i struggled a lot making the cardboard templates. maybe it's a learning curve or maybe i was shivering uncontrollably. combination of the two? either way, i'm very happy with how it turned out.

i had to attach the baffles on top of the port because the mounting depth of the 6.5's. tuning will drop a bit but i'm not too worried about it. bass still sounds good. goes right up to the seats.

the 6.5's sound pretty good, get really loud too. much smoother than when i had the 4 6x9s and 4 tweeters in, those cranked felt like a punch in the head.

so ya, all i have left to do now is grab another 3500 //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[irpirate]

update time!!! first off, i've bitched a lot about my car idling at 600 engine rpm. i wanted to stay away from using the tensioner thinger under the hood but decided to screw gas mileage, already have this much weight in the car, what's a high idle gonna do?.. anyways i live in iowa, worst traffic around here is getting stuck behind a tractor. clamped my 270xp at idle last night, 600 rpm ~159. after i did the adjustment and set the idle to 1300 (may be a littttleee too high but fug it, MooarARRRr PooOWWAA!) at 1300 ~205-212.

and todaayyy, i was waiting for the nice ups man to stop by. realized i didn't have any fuse holders left so i quick **** rigged a couple (didn't want to wait if i ordered them)

ugly, cheap and works great

then around 5 pm the ups came!! was smoking cigs and drinking soda like crazy trying to stay awake lol.

lalalaalallalallaaaa~~~

50 feet 1/0 welding cable. stuff is amazingly flexible even when it's borderline frozen.

this was it was after the wire was sitting in 25 degree coldness for about an hour.

^_^

didn't take any pictures but i added 5 runs of 1/0 on top of the two runs of 3/0 i already have there. 2 positive 3 negative.

 

[irpirate]

picture limit :/

original 3500 and 850.4

new one!!!

ghetto fuse holder in action!!

and my sloppy wiring keeps getting sloppier lol

was around 20-25 degrees the entire time i was working outside. i literally couldn't feel my hands for the last hour or so. completely worth it //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif. it's up and playing. i set the gains with a dmm for 3000 rms @ 1 ohm per amp, gonna take it up a couple notches tomorrow, give 3500-3600 per a try. after driving out to the middle of nowhere and beating on it i'm pretty sure the subs can take more. voltage is doing much much much much x 9002390234 much better. not much of a drop on most songs, only a couple of decaf's songs or sine waves full tilt drop me in the 12's. it was too dark for me take lots of pictures or get a good video so i'll get on that tomorrow. also gonna see if i can't properly seal this *****. all i can think of for now, vids, more pics and updates to come soon!