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View Full Version : Need help sub sounds HORRIBLE!



Audio_n00b
06-12-2003, 03:34 AM
I got a 10w3 sub, Mtx 300 watt amp and a Alpine 9807 HU. the sub works im gettin power. but... it doesnt seem to want to pound. i get alot of gargle and i guess... distortion when i change the track of a cd. ive tried tunning it and it just doesnt want to sound good and BUMP like it should just sounds really weak and powerless. I wired the sub identical to the JL dvc chart listed here. the 2nd method down is the one i used.

http://www.jlaudio.com/tutorials/wiring/index.html

i checked all connections and grounds. please help... if u need any more info just let me know. Thanx alot for your help.

Mark_ab
06-12-2003, 03:38 AM
Perhaps a bad RCA connection

Audio_n00b
06-12-2003, 03:41 AM
nope checked that too... how can u tell if the sub is blown?

maylar
06-12-2003, 08:13 AM
did you set the amp to lowpass mode?

ramos
06-12-2003, 08:42 AM
MR. Maylar is on the right track . I would also see what your gain is set at. :)

Audio_n00b
06-12-2003, 09:23 AM
there is no low pass mode. my gain doesnt even have to be a 8th of the way up before it starts gargeling.... and it doesnt have to be up at all when i switch tracks i get wierd noise.

loserpunk
06-12-2003, 09:34 AM
if your cone is moving then the sub isn't blown.....and what are the specs on the amp

Audio_n00b
06-12-2003, 09:44 AM
its a mtx 250d pusing a single 10w3

http://www.mtx.com/caraudio/archive/thunder250d.cfm

ramos
06-12-2003, 10:31 AM
If you have a multimeter check the resistance of the voice coils indivdually. It should be somewhere around the nominal impedence of the subs. If the resistance is infinite or 0 your sub is toast. But before you do that. What kind of enclosure and what's the volume of the enclosure ? :)

Audio_n00b
06-12-2003, 03:16 PM
ive got a q logic box its .65 cubic feet 21 w x 13 3/4 h x 8 1/4 bd x 5 1/4 td

ramos
06-12-2003, 04:20 PM
Well it's a small sealed enclosure so that could be part of the reason it doesn't seem to be hitting very hard. What are you comparing the output to ? Another system you had previously, someone elses system ?


Did you check the impedence of the coils ?

i'm searching for a clue man. Have patience and we will find your problem. :)

Audio_n00b
06-12-2003, 05:15 PM
yea i just used the Continuity setting on my multi meter. (hope its right setting) and i got 3 ohms on each coil. Im new to the audio scene i use to have 2 10 inch kenwoods in a bandpass and it hit decent. i figured this would atleast hit but its almost drowned out by the trucks stock speakers. i have a s10.

loserpunk
06-12-2003, 05:23 PM
if you got 3 ohms then your coils are fine....gotta be something else....you should be getting enough power from your amp.....approx 175-200 at 3 ohms....not sure what's wrong....

loserpunk
06-12-2003, 05:25 PM
the only thing i can think of is that maybe by accident you wired it wrong...instead of + to + and - to - you mixed one up and went + to - and - to +...that'll give you a 12ohm load.....at that load you won't be getting nearly enough power....if not...then i don't knwo

ramos
06-12-2003, 05:26 PM
Originally posted by Audio_n00b
yea i just used the Continuity setting on my multi meter. (hope its right setting) and i got 3 ohms on each coil. Im new to the audio scene i use to have 2 10 inch kenwoods in a bandpass and it hit decent. i figured this would atleast hit but its almost drowned out by the trucks stock speakers. i have a s10.


Okay the sub is fine then. Now we are getting somewhere. :) The single 10 in a sealed box isn't going to be even remotely close to the output of the dual 10's in a bandpass. The sealed box will have the flattest response curve. Meaning will sound the best over the whole frequency range the sub is playing. While the bandpass box is going to destroy the sealed box in output. But only in a certain range depending on the box tuning. The bandpass box has a very narrow frequency response hence the name bandpass.
I got this feeling the voice coils are actually bottoming out and that is what the sound you here is.
Try this turn the gain all the way down on the amp. Then turn your volume up to about 3/4. Now adjust slowly turn your gain up until you here the same noise. Then just back it down slightly. Tell me how high you can turn the gain up this way until you here your weird sounds again :)

loserpunk
06-12-2003, 05:28 PM
sorry for so many posts..sometimes i talk to fast and don't think...whats' the coil config on the sub....

ramos
06-12-2003, 05:31 PM
Originally posted by loserpunk
if you got 3 ohms then your coils are fine....gotta be something else....you should be getting enough power from your amp.....approx 175-200 at 3 ohms....not sure what's wrong....



Nah man. It would be a 1.5ohm nominal load if the two 3ohm coils are wired in parallel.
Wired in series it would be a 6ohm load. But your right if you accidentally wired the sub series + to -, - to +. It would cut the power from the amp in half. :)

loserpunk
06-12-2003, 05:44 PM
yea for some reason i was thinking they were 6 ohm coil....jl = (imo) 6 ohm coils and other wierd configs....sorry bout the bad info...where does it say they're 3 ohm....or are you taking that from what he got on the multimeter....

Audio_n00b
06-12-2003, 06:04 PM
well i can have the gain completely off. and when i change a track or when commercials switch or a pause in a song lots of distortion. i mean shouldnt i be able to notice a huge difference in the base? my base sounds almost identical as it was before i got the sub. just alittle more gargle and distortion even with gain no more then 1/8 of the way up.

Yes my wiring is all ok. connections fine.

the 3 ohms is from the Continuity setting on my MM i dont even know if thats the right setting. maybe there is a specific setting? it ranges from 2m down to 2k then it has a buzz tone for continuity and a ->+ continuity setting. i used the ->+ continutiy setting and thats where i got 3 ohms. i tried the others and got a different number every second so i figured it was wrong setting. correct me if im wrong.

Thanx for the help... so far =)

ramos
06-12-2003, 06:09 PM
Originally posted by loserpunk
yea for some reason i was thinking they were 6 ohm coil....jl = (imo) 6 ohm coils and other wierd configs....sorry bout the bad info...where does it say they're 3 ohm....or are you taking that from what he got on the multimeter....



From what he said. Even though the subs will say either dual 4's or dual 2's. They aren't usually right on the money. It's not uncommon for the voice coils impedence to be higher or lower than the rated impedence. That's why they are always listed as Nominal impedence. Jl has the wierd configs for the 3 sub setup. That was the big thing when they first appeared. :)

ramos
06-12-2003, 06:12 PM
Originally posted by Audio_n00b
well i can have the gain completely off. and when i change a track or when commercials switch or a pause in a song lots of distortion. i mean shouldnt i be able to notice a huge difference in the base? my base sounds almost identical as it was before i got the sub. just alittle more gargle and distortion even with gain no more then 1/8 of the way up.

Yes my wiring is all ok. connections fine.

the 3 ohms is from the Continuity setting on my MM i dont even know if thats the right setting. maybe there is a specific setting? it ranges from 2m down to 2k then it has a buzz tone for continuity and a ->+ continuity setting. i used the ->+ continutiy setting and thats where i got 3 ohms. i tried the others and got a different number every second so i figured it was wrong setting. correct me if im wrong.

Thanx for the help... so far =)


So even with the gain all the way down you still hear the sound ? Now we are really starting to get somewhere. Have you tried a different sub with the amp ? :)

Audio_n00b
06-12-2003, 06:12 PM
ok i just read the little book and now i got the right setting

its about 3.7 ohms so i say 4 ohms each coil

Audio_n00b
06-12-2003, 06:13 PM
No i have no other subs =(

ramos
06-12-2003, 06:18 PM
Oops I'm an idiot read below :)


I don't know what I was thinking. To make a muting plug you need to simply connect the inner pin and outer shield of the rca cable together. I just took a cheap rca cable cut one connector off with about 4" of wire remaining connected to the connector. Then stripped the wire and twisted the two together. Then unplug your regular rca's from the amp. and plug the muting plug in. You shouldn't here anything at all. let me know what you here :)

ramos
06-12-2003, 06:19 PM
Originally posted by Audio_n00b
ok i just read the little book and now i got the right setting

its about 3.7 ohms so i say 4 ohms each coil


So the amp is being presented roughly a 2ohm load. :)

Audio_n00b
06-12-2003, 06:21 PM
ok, well $h*t battery in truck just went dead.... ummm let me charge it up for a few hours then take it for a spine and ill try that out ;) thanx for your help ill be back on in a few hours.

Erik

ramos
06-12-2003, 06:23 PM
Originally posted by Audio_n00b
ok, well $h*t battery in truck just went dead.... ummm let me charge it up for a few hours then take it for a spine and ill try that out ;) thanx for your help ill be back on in a few hours.

Erik


Cool man. we are making progress. We allready ruled out the sub. Now we are moving onto the amp :D Let me know :)

Audio_n00b
06-13-2003, 08:48 AM
ok i did that and i heard nothing.

ramos
06-13-2003, 11:13 AM
Originally posted by ramos
Oops I'm an idiot read below :)


I don't know what I was thinking. To make a muting plug you need to simply connect the inner pin and outer shield of the rca cable together. I just took a cheap rca cable cut one connector off with about 4" of wire remaining connected to the connector. Then stripped the wire and twisted the two together. Then unplug your regular rca's from the amp. and plug the muting plug in. You shouldn't here anything at all. let me know what you here :)


Did you try it this way or the first way ? This is the way i was refering to. I didn't get much sleep yesterday :D :)

Audio_n00b
06-13-2003, 11:43 AM
yea i tried it the 2nd way ;)

but now... im having a diffent problem SIGH... now im not gettin any sound what so ever from the speaker. the cone is moving up and down. but no sound.

slipknot87420
06-13-2003, 11:58 AM
are you wanting the high's to come through your sub like the voices???

Audio_n00b
06-13-2003, 11:59 AM
no...

slipknot87420
06-13-2003, 12:08 PM
oh ok it's just that it kinda sounded like you wanted the highs to come through your sub:)

Audio_n00b
06-13-2003, 12:10 PM
nah just trying to figure out why its not hitting. ive got no sound at all right now. i had MASS distortion before. so i dont know whats up :( subs not blow brand new alpine head unit and almost brand new amp and Jl 10w3

ramos
06-13-2003, 12:14 PM
Allright then. We have ruled out the sub, amp, your amp wiring, and your amp ground. This might sound a little stupid but have you checked your bass settings and any other sound enhancement features on your deck ? Does the deck have a seperate sub output ? Can the sub output be turned on or off ? Is it on ? Lots of questions still digging :D ;)

d audio 450
06-13-2003, 12:15 PM
sounds like the sub is out of phase...i mean if the cone is moving and your not hearing much, my first guess is that there is an error in hooking it up or somethin- did u double check your wiring? make sure all polarities are correct...
-pat

Audio_n00b
06-13-2003, 12:20 PM
yea HU has sep. sub outs. sub is on. i even used the Power off feature on the HU to turn off the HU amp so that just the MTX amp would be powerd and i got no sound what so ever. the cone just moved.

My ground is about 8-10 inches away from my amp. i chipped away the paint and drilled tapped a 3/8s bolt and its tight. the cd player ground is crimped/spliced and extended just below the dash where i did same grounding method as above. and as far as i know ive used every settin on the HU there is trying to figure this out. only thing i can think is wrong is maybe bad rca's.

ramos
06-13-2003, 12:24 PM
D@mn this is alot harder without actually having the car in front of me :D I would try switching the phase of the sub ( reverse your wires running to the sub at the amp) first. See what happens. No difference. Try switching the RCA's. And see what happens. :)

Audio_n00b
06-13-2003, 12:46 PM
ok tried the polarity nothing. then the rcas and nothing. PFFFT! this is making me so **** mad.

ramos
06-13-2003, 01:56 PM
Hmmmm....... Do you know anybody else that has a sub ? Maybe you can try there sub with your amp. I'm grasping for straws now man. :)

Audio_n00b
06-14-2003, 08:28 AM
i figured it out... LOL im a dumbassss. instead of hookin up a + and a - from each coil i hooked up the + and - from the same coil to the amp. so only 1 coil was workin and thats why it was so weak. SORRY FOR ALL THE TROUBLE!!! but thanx for the help its nice to know if ur introuble u can count on this forum for help

MikeofTulsa
06-14-2003, 08:19 PM
jackass......j/k man.....glad to hear its workin for ya tho....

loserpunk
06-14-2003, 10:45 PM
yea good thing you finally figured it out

ramos
06-17-2003, 11:10 AM
Originally posted by Audio_n00b
i figured it out... LOL im a dumbassss. instead of hookin up a + and a - from each coil i hooked up the + and - from the same coil to the amp. so only 1 coil was workin and thats why it was so weak. SORRY FOR ALL THE TROUBLE!!! but thanx for the help its nice to know if ur introuble u can count on this forum for help


:nono: :nono: Always triple check all of your wiring. Everyone has stupid moments. I tend to have alot :D :)

ngsm13
06-17-2003, 11:19 AM
Originally posted by ramos
:nono: :nono: Always triple check all of your wiring. Everyone has stupid moments. I tend to have alot :D :)

that's what hapenned when i first wire up my k's...i took a + and - from each coil instead of +/+ and -/- then when i fixed it i was amazed. peace...and where u live in cincy??? if u ever need ne help i could help ya out...that's where i live. lmk...peace

NG

Audio_n00b
06-17-2003, 02:08 PM
i dont really live in cincy i live right across the river in Highland heights KY. cincy is about 5 mins from my house so i just say i live there ;)