Having a very hard time getting help. PROS ONLY!

[mendon mafia 10+ year member]

ok so before i talk about my enclosure lets talk about what could cause the "symptoms" that i am having with my subs.

Subs can take all the power in the world below 40hz. between 40-50 its a little iffy and above 50 my subs are completely out of control over extending and distorting like mad. BTW i have 2 12" rd alpha v3/v2's.

i realize that the subs should hardly move when playing at tuning but the subs should move more below tuning than above right? all my problems are above tuning. even below tuning the power handling is exceptional and no distortion.

On the song hypnotize by young jeezy the 2 low notes (34 and 37 IIRC) absolutely kill and i can crank the volume all the way up with no problems at all. They keep getting louder and sound clean doing it. but when the high note hits (51hz IIRC) the subs distort terribly and sound VERY bad and move way farther than on the other 2 notes.

So what can cause the problems im having?

PLEASE HELP.

ok so now that you have thought about that for a minuite i can tell you i hav an atomic 3000.1d amplifier, and my enclosures spec out to 2 cubes net tuned to 37hz.

heres some pics of the box, the dimensions are 18.5 wide, 13.5 tall, and 31 long, the port is 4" wide x 12" tall. The port wall lengths are 26.25 and 8

The RE calc says its 2.329 cubes @ 34.46hz but that calc doesn't factor in the double front baffle or driver displacement so thats how i get my numbers for volume and tuning.

Click to read more...

 

[CRXBMPN 5,000+ posts]

my old subs used to unload like a bish well over tuning frequency, they go WAAOOOOWWAAAAOOOOOWWAAAAAAAAOOOOOOOOWWWWWWWWWWW and look like they are hovering up and down lol...

 

[Supergumby5000 5,000+ posts]

1) thasa big port for one sub

2) set your filters on your amp correctly

3) check headunit equilizer/filter settings

 

[CRXBMPN 5,000+ posts]

1) thasa big port for one sub
2) set your filters on your amp correctly

3) check headunit equilizer/filter settings

i cant see the pix but he says he has two 12's...

turn the high pass down a bit too, or maybe steepen the crossover if you can on the amp (mins is either full, 12db/oct, or 24db/oct)

 

[hornedfrog1985 5,000+ posts]

3000 rms on a single alpha?

He says he has a v3/v2, and only shows one sub. I assume he switches them out or whatever.

 

[altoncustomtech 10+ year member]

Pro... no...... experience.... yes..... sounds to me like you're plain and simply overdriving the amp or having voltage drop issues..... when playing near tuning frequencies you're impedence rise is in the optimal range for the given system and it's happy... once you rise above it you have trouble..... another thing that isn't helping anything is trying to run that much power through that little bitty speaker wire to your subs.... the wires are adding to your impedence problems as well.....

that's my .02.... right or wrong that's where I feel you're troubles are coming in comparison to your expectations of the system....

 

[mendon mafia 10+ year member]

ok to clarify all the problems i have 2 seperate boxes which i run BOTH at the same time usually. the specs given are for one box. so multiply by 2 and there ya go.

My amp is used for both subs. wired down to .5 ohm. (1 ohm when im using 1 sub) problem still happens either using 1 or 2 subs.

voltage drop is not a problem i dip into the mid 12's at the lowest. got a 200 amp alt 2 spv70's and a stock batt. only 1 run of 1/0 tho for pos and ground. but as stated before my voltage drop isint that bad.

all my filter and eq settings are set correctly. flat on the eq. filter on the hu is set at 80hz, filter on the amp is probably at 70. If i cross down to 50 i will have no output between 50-80 hz, my momo components are nowhere near as loud as my aplhas. and dont really start hitting until about 80-100hz. (I need speaker pods my doors **** for sealing)

My speaker wire is 10 gauge and i have separate runs for each woofer directly from the amp. the wire shown was just for testing.

Imp rise might be a very likely cause but how do i get around this. never had this problem before. and ive built tons of boxes and systems. non having this large of port area though. but thor and all those other guys with big ports dont have this problem either so idk.

 

[altoncustomtech 10+ year member]

ok to clarify all the problems i have 2 seperate boxes which i run BOTH at the same time usually. the specs given are for one box. so multiply by 2 and there ya go.
My amp is used for both subs. wired down to .5 ohm. (1 ohm when im using 1 sub) problem still happens either using 1 or 2 subs.

voltage drop is not a problem i dip into the mid 12's at the lowest. got a 200 amp alt 2 spv70's and a stock batt. only 1 run of 1/0 tho for pos and ground. but as stated before my voltage drop isint that bad.

all my filter and eq settings are set correctly. flat on the eq. filter on the hu is set at 80hz, filter on the amp is probably at 70. If i cross down to 50 i will have no output between 50-80 hz, my momo components are nowhere near as loud as my aplhas. and dont really start hitting until about 80-100hz. (I need speaker pods my doors **** for sealing)

My speaker wire is 10 gauge and i have separate runs for each woofer directly from the amp. the wire shown was just for testing.

Imp rise might be a very likely cause but how do i get around this. never had this problem before. and ive built tons of boxes and systems. non having this large of port area though. but thor and all those other guys with big ports dont have this problem either so idk.

sounds like you have most all things covered.... imp rise problems would require a rebuild of the box I would imagine.... there's a few good books like "Bullock on Boxes" that can explain imp rise in box design, you might look that one up for reference purposes.... otherwise I'm gonna stay out of the rest of the discussion as anything else I would suggest seems to be covered and my understanding of imp rise is pretty basic at this time.... Good Luck man, hope you get it figured out without too much trouble ahead...

 

[mendon mafia 10+ year member]

Ok so i just took a vid so yall can see my problems. its uploading to youtube should be about 20 minutes.

I took the vid using only 1 sub and running just off the alt and stock batt. my voltage only dips down to like 13 though.

you can clearly see how much farther the sub moves on the high note than the lows. not sure if you can hear the distortion or not but you can imagine.

 

[mendon mafia 10+ year member]

3000 rms on a single alpha?
He says he has a v3/v2, and only shows one sub. I assume he switches them out or whatever.

o and btw by v2/v3 i mean idk which they are. they were told to be v2 by steve miller but as soon as i got mine other ppl started calling them v3. mine have the ti former, 55mm fw coil and a probably all of the same features of the v3's not sure what the diff is other than that anyways. these were supposed to be able to take 2kw rms. Ive actually fed one of them nearly all 3kw and it did take it as long as it was a low note.

 

[mendon mafia 10+ year member]

VID



@ 1:10 in i turn it up more so that it starts distorting. Before 1:10 its still clean sounding.

 

[bubbagumper6 5,000+ posts]

I see the problem...it's those gay *** led's you have under your dash //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

 

[spltuscon 10+ year member]

Your net volume is 1.93 and your tuning is 38.7, so your numbers are a bit off. The RE calculator sucks so I would find a different one if I were you.

That aside...you can still push your subs past their limits above tuning when you're giving them a lot of power. Have you checked to see if your box has a leak or a weak seam somewhere? Could be frequency dependant or something....

You don't have loudness or any other form of bass boost/bbe on do you?

 

[mendon mafia 10+ year member]

Your net volume is 1.93 and your tuning is 38.7, so your numbers are a bit off. The RE calculator sucks so I would find a different one if I were you.That aside...you can still push your subs past their limits above tuning when you're giving them a lot of power. Have you checked to see if your box has a leak or a weak seam somewhere? Could be frequency dependant or something....

You don't have loudness or any other form of bass boost/bbe on do you?

eq is on flat. bass boost is off. loudness is off. all bass setting on hu are at 0. gains set using dmm.

Box was built using gorilla glue and definitely does not leak. This is like my 10th enclosure build so im not a novice and ive never had a problem like this. I guess i need to try a new box.

I dont think im overpowering the sub considering my voltage drop and the fact that im only using my stock battery in the vid.

How do you figure the measurements you calculated? i was think more around 2.1 and 37 hz

 

[mendon mafia 10+ year member]

I see the problem...it's those gay *** led's you have under your dash //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

there under my seats too so theres no shadows and i got the rear lit up too 6 strips in all still need to hide them a little better.

lol and dont hate just cuz you havent installed yours yet //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif