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i have 2 12" nightshades and their getting very hot and smelly after about 30 secs to a 1 min of playing, and no low end

my system consist of:

hu: JVC kw-nx7000

sub: 2 12" D1 Sundown Nightshades

sub box: 4 cubes @ 34hz, kerfed port

sub amp: 2 audioque 2200ds strapped

battery: (front)Duralast Gold;(back) 2x Deka Intimidator g31

electrical: Mechman 270a, big 3 in 1/0 gauge knu flex

i cant figure out whats going on. i hooked them up to each amp (not strapped) and doing the same thing. it doesnt get as hot, but still gets hot and no low end. it sounds like my ssf is set to 34hz. anything below that is inaudible (ssf is set to around 25). and they bottom out vey easy

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What are the specs of your box ie width, height, depth, port lengths etc. Sounds like the box isn't tuned to what you think it is.

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What are the specs of your box ie width, height, depth, port lengths etc. Sounds like the box isn't tuned to what you think it is.

thats the same thing i thought. i talked to the guy how design and help me build it and he conformed that it was tuned to 34hz.

w- 36

h- 15.5

d- 20

got the design from somebody else and iamamp3pimp changed it to a kerfed port

newbox.jpg

SANY0031.jpg

SANY0066.jpg

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Most likely cause is a box issue. 2nd most likely cause is a setting issue on the amp and/or head unit. Are you running the amps @ 0.5ohm?

I just did some quick math off your pic.

36" wide x 15.5" tall x 20" deep = 5.17ft gross internal volume

4.5" wide x 14" tall port (63" of port area) = 30" long for a 34hz tune. Your pic does not show total port length so I can't verify tuning.

Assuming tuning is correct then port displacement = 1.24ft Technically it's a little more because of the flares.

sub displacement = 0.45ft

That means net box volume can't be anymore than 3.48ft. If I calculated for all the angled corners and flares then actual net volume is probably somewhere around 3.25ft. 3.25ft net volume with a 30" long port = 38hz tuning.

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Wired out of phase? Clipping the amps? That would explain a lot more than an improperly tuned enclosure.

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Most likely cause is a box issue. 2nd most likely cause is a setting issue on the amp and/or head unit. Are you running the amps @ 0.5ohm?

I just did some quick math off your pic.

36" wide x 15.5" tall x 20" deep = 5.17ft gross internal volume

4.5" wide x 14" tall port (63" of port area) = 30" long for a 34hz tune. Your pic does not show total port length so I can't verify tuning.

Assuming tuning is correct then port displacement = 1.24ft Technically it's a little more because of the flares.

sub displacement = 0.45ft

That means net box volume can't be anymore than 3.48ft. If I calculated for all the angled corners and flares then actual net volume is probably somewhere around 3.25ft. 3.25ft net volume with a 30" long port = 38hz tuning.

no setting issues. yea there @ .5ohm.

oh wow! didnt know that.

the orginal ports are 14.75 and 10". not sue about the kerfed 1.

but even if its at 38hz, it should still be able to hit 32hz rite?

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Wired out of phase? Clipping the amps? That would explain a lot more than an improperly tuned enclosure.

wiring shouldnt be a problem.

the aqs have a clipping indicator on them, but i can get them to get hot and smelly on half power. so i dont think clipping is the problem

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How far are they moving ?

IIRC I used three progressive spiders on those as they were for me -- they are pretty stiff.

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How far are they moving ?

IIRC I used three progressive spiders on those as they were for me -- they are pretty stiff.

not sure how far they are moving. ill check when i get off of work.

they are still pretty stiff. but something just isnt right. i shouldnt be able to smell the subs after ~30 secs of playing them. and anything under 34 hz is inaudible.

p.s. i liked that they are custom from you, gets me a closer to the man :wub:

(no homo lol)

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Smelling a coil isn't really abnormal per-se. Warms coils have a smell to them especially when new.

Without clamping them you don't have any way to know what the power vs. frequency looks like. You may be jamming a ton of power on them when it drops under tuning.

If they aren't moving sufficiently then cooling is also hindered. These are pole plugged drivers as well so the air velocity is pretty high exiting the driver -- this gets the "smelly" hot air to you a bit quicker.

Two things can be done to "get them moving" if they aren't moving much now -- you can use a larger enclosure or re-cone them with a different suspension. Either option will also increase bottom end extension.

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Smelling a coil isn't really abnormal per-se. Warms coils have a smell to them especially when new.

Without clamping them you don't have any way to know what the power vs. frequency looks like. You may be jamming a ton of power on them when it drops under tuning.

If they aren't moving sufficiently then cooling is also hindered. These are pole plugged drivers as well so the air velocity is pretty high exiting the driver -- this gets the "smelly" hot air to you a bit quicker.

Two things can be done to "get them moving" if they aren't moving much now -- you can use a larger enclosure or re-cone them with a different suspension. Either option will also increase bottom end extension.

oh ok.

not able to check today, its raining real hard.

but if i was to do recones, will it be the original NS or the new v.2 cones?

another thing, derrick made a good point. what is you opinion on the box?

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