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acold7dusta
09-23-2006, 10:06 PM
recently i made a box for my diamond D6 sub. internal dimensions are 38.5 x 12.5 x 8.5, which brings it to 2.1 after sub displacement. i put a 3", 9.25" long tuning it to about 28 hz. this is WAY too low for this sub. I barely hear any notes besides the real low ones. put my ear up to the speaker, and it was making like a squeeking noise when its supposed to hit, but doesnt. I'd prolly do alot of damage if i continued it like this.

which bring me to my next question: i love how ported boxes sound, so can anybody tell me what tuning range this sub likes (for the most flat response), and how much to trim the port, or is there a way to seal off the box to make a small sealed box? i really dont wanna trash this box and make another one, but i guess i could if all else fails.

thanks in advanced,
kev

iamamp3pimp
09-23-2006, 10:11 PM
make a new one


its cheaper thatn ptentialy destroying your speaker.

Robin

thatkidbob
09-23-2006, 10:35 PM
i need a picture of this box so i can figure out whats going on...

acold7dusta
09-23-2006, 10:37 PM
http://www.imagestation.com/picture/sraid214/pa5ab5dba8cd15519032a17d69ac01d8c/ed2405a3.jpg

minues the back plate

thatkidbob
09-23-2006, 10:42 PM
wierd... i don't see any obvious construction errors... and 400 watts in 2 cubes shouldn't hurt that sub..

i'm unsure of what could cause problems like what you're describing...

does the sub sound regular outside of the box?
when you press straight down on the cone does it rub at all?
do you have access to a DMM? if so check out the voice coils...

iamamp3pimp
09-23-2006, 10:47 PM
thats a 12, right?



that isnt very much port area imo

iamamp3pimp
09-23-2006, 10:47 PM
espically for such a large box.

acold7dusta
09-23-2006, 10:53 PM
the sub is perfectly fine, its brand new. I think since its tuned too low for it (only a 10"), so heres how im gonna describe it. When the lower drum notes that are supposed to hit, dont, the sub kinda makes a squeek/ rattling noise. when it gets to a real low note (late nite tip for example, it get amazingly low and sooo much output, enough to shake the car on higher volumes.
Playing Incubus "circles", for example , i get port noise and missing ALOT of the notes, except the real low notes. Im still scratchin my head, but im keyin in that box is not tuned properly for that sub. Diamond recomends tuning it to 35 hz @ 1.25 cu ft slot port....

thatkidbob
09-23-2006, 10:54 PM
^ i've put bigger in smaller lol...

it shouldn't be making squeeking noises, and it shouldn't be as quiet as he makes it sound...

thatkidbob
09-23-2006, 10:57 PM
the box is tuned fine... 7hz wouldn't make THAT much difference.

i've switched camps... the port is too small...

build something with at least 25 sq inches of port (btw, your box is about to become a LOT bigger) and chances are the probem will disappear...

acold7dusta
09-23-2006, 10:59 PM
i know, the whole thing is baffling, i think iamamp3pimp and thatkidbob may be right, with the too small of a port area. it kinda sounds like the woofer is free airing, if you know what i mean. like the suspension wants to go, but its not feeding enough air?

thatkidbob
09-23-2006, 11:01 PM
what are the settings on your HU and amplifier?

acold7dusta
09-23-2006, 11:21 PM
+3 on the head unit (out of 15) and the amp the gains at about 3:00 right now, bass boost a lil over 1/4, the LPF is 80 hz, subsonic around 30 hz, phase 0 degrees. the more i think of it, the more it kinda reminds me of a large, leaky sealed box. if i add another 3" port, in addition the one i got, would that raise or lower my tuning, assuming the ports the same exact length

also, would it matter the length from the port in relation to the sub?

thatkidbob
09-23-2006, 11:44 PM
its going to raise your tuning...

some people believe the port should be as far away from the subs as possible, but i don't know or understand the rationale behind that. If you've got a DMM laying around i'd reset the gains with it (but i doubt this is the problem), but other than that i don't see any problems with your settings.

if it isn't the amp, HU, sub, or your settings, the only thing left (by elimination) is the box. If you'd like you can add another port, but this will raise your tuning significantly. It'll be just a hair over 39hz. edit: this is also going to increase your port velocity issue...

acold7dusta
09-23-2006, 11:51 PM
what if i put a baffle inside it to slow the back wave. say a board 12.5 x 5.5 (4 inches smaller than the depth) stuck a few inches away from the woofer?
ive been messing around left and right with the settings, so its def not the settings. its definately the box.

acold7dusta
09-24-2006, 08:28 AM
morning bump, do you think i should put that baffle in there, or should i just seal it off completely?

MikeyB
09-24-2006, 08:34 AM
Turn off your bass boost and resetting your gain and then listen to it, I think this is your problem, it still should hit those other notes, maybe not as hard but it should still play them.

iamamp3pimp
09-24-2006, 08:37 AM
the box is tuned fine... 7hz wouldn't make THAT much difference.

i've switched camps... the port is too small...

build something with at least 25 sq inches of port (btw, your box is about to become a LOT bigger) and chances are the probem will disappear...

im gonna have to disagree with you on that one.

in his case, 7 HZ is a quarter octave. that is a huge difference. tuune it higher, and use 2 3 inch ports instead of one

acold7dusta
09-24-2006, 08:48 AM
how will 39 hz sound with normal music? i listen to alot of tool, trance, and anything very musical, and i cant have something peaky or something that cant produce the lows very well

acold7dusta
09-24-2006, 11:36 AM
i think im just gonna make a small sealed box, like .6 or .7 cu ft

iamamp3pimp
09-24-2006, 12:58 PM
39 hz is too high


id try 32

acold7dusta
09-24-2006, 01:03 PM
truth hurts....
http://www.imagestation.com/picture/sraid215/p592f0086a6046a5bbc9cb35da5aeeb86/ecd5204e.jpg
:blackeye:

PowerNaudio
09-24-2006, 03:13 PM
+3 on the head unit (out of 15) and the amp the gains at about 3:00 right now, bass boost a lil over 1/4, the LPF is 80 hz, subsonic around 30 hz, phase 0 degrees. the more i think of it, the more it kinda reminds me of a large, leaky sealed box. if i add another 3" port, in addition the one i got, would that raise or lower my tuning, assuming the ports the same exact length

also, would it matter the length from the port in relation to the sub?


truth hurts....
http://www.imagestation.com/picture/sraid215/p592f0086a6046a5bbc9cb35da5aeeb86/ecd5204e.jpg
:blackeye:


between the graph, cabin gains and your settings youre super re-enforcing the low end way too much. thats why you feel like youre lacking the upper end and seem like youre going to destroy your sub. you need to bring the low end down. so take the bass boost off.
raise the LPF to 120Hz to allow for the higher end to not get cutoff and actualy play. i have no idea what the q setting on the LPF is, so thats one reason to raise the LPF cut off point higher. lower your sub bass freqs on your head unit. and if you have bass boost on your cd player again turn it off. if you have filters re-check and set to 0. this is to avoid you making a new enclosure. you can keep your subsonic to 30Hz or rais it some to cut off the low end slightly. the enclosure may have not been design with allot of the sub specs and mechanical abilities in mind. most likely designed for the sacke of low bass. and **** the sub. lol

try your settings, if all eals fails, then a new enclosure or changing that port and change internal volume is at hand.

laters

acold7dusta
09-24-2006, 11:15 PM
i spent the last 5 hours blocking off the box. its about .7 or .8 now, and i got all my notes back. VERY musical...i love it, i was surprised at the low end output that i still get. definately not as thunderous at lower hz but sounds AMAZING. very happy at the results

PowerNaudio
09-24-2006, 11:32 PM
i spent the last 5 hours blocking off the box. its about .7 or .8 now, and i got all my notes back. VERY musical...i love it, i was surprised at the low end output that i still get. definately not as thunderous at lower hz but sounds AMAZING. very happy at the results

what do you mean by blocking of the box? you sealed the port? or just cut up the enclosure and made it smaller?

acold7dusta
09-25-2006, 02:25 PM
i cut up the enclosure and made a real small sealed box. it hits good, nothin special really. nothing like a properly tuned ported box :( i just miss my lows now, o well, it blends really good now. i might make the ported box that diamond recomends next year. its 1.25 tuned to 31 or 35 hz, and they give all the cut dimensions so i wont F* up and make it wayyy too big lol