Today I finished my ported box and I was removing my sub from my old sealed box and when I put it down something inside the sub sounded like it was rattleing. Also when I push the cone in a little bit it makes a scraping/scratching sound. I havn't been abusing my sub or running it into clipping, and this has never happened.
Anybody have any ideas on what this could be or is this not a big deal. I doubt this is normal, never heard anybodys speakers make this noise before.
Thanks in advance,
Jay
PS its an Alpine SWR-1241D running off a JBL 300.1
Replies (7)
P0werLifter on 08/26/2004 02:23:26
This is not my area of expertise but to me it sounds like the speaker cone has seperated from the spider or something with the voice coils. Im not positive tho, Swez and some of the others are more versed in this area...check on Chrono's post about "ED vs ADIRE" theres some info on there that could help you out.
-Jason
uochronos on 08/26/2004 02:35:25
yes definatly read what swez said in my post it well help you a bit here... sounds like the voie coil is rubbing or something similar... i cant say that this is good anytime the sub makes a scratching sound at little movement... if its still under warranty i suggest sending it in.
Munchiesyumm on 08/26/2004 11:55:06
I will suggest that you play with the LP filter. (low pass filter) This will change the sound of the sub making it more punchy or more bassy.
I know JBL amplifier's are a little more difficult to set sense you're kinda blind where you're setting the nob. They don't mark 50hz, 70hz ect.. When you're setting it keep the volume semi low but loud enough to listen for the distortion to clear. Once you find where you like it turn it up to the desired loudness and listen for any distorion. Check both from close up and farther away and inside the car. This is how you get that perfect bass notes u like. I'll let you be the judge on the bass boost 3-6db is okay depending on the application.
have a great day!
I just fixed a problem like this the other day in about 6 minutes. Remember that a sub that is not properly tuned will eventually blow.
As for pushing down on the cone you should hear some noise from the cone moving up and down but this is normal. You'll know the difference between a blown sub and a good sub, the blown one will push down really easily. Trust me on this when a sub blows you'll find out reall quick!
compvr15s on 08/26/2004 18:41:37
it definitly sounds like an issue with the voice coil. nothing else inside the sub should make a scratching sound, did you make sure you pushed strait down on the cone, if you kind of force it to one side this will happen.... when pushin down the sub should feel normal no tension, if the VC is cooked you will definitly know, in all the solos that i fried, once the cone quit moving it too tremendous force to realese the sub... dont know if this is because it melted to something or what... i really doubt your sub is blown, you would know by a destinctive smell.. id imagine it just seperated or somehting along those lines. have you tried runnin the sub yet??
swez on 08/26/2004 19:53:44
Here's how to diagnose a blown/damaged woofer:
1. Some sound, but lots of rubbing scraping is heard. Voice coil was burned or charred... Can hear scratching/rubbing sounds, when you manually pump the cone, with no power to sub. You may even be able to smell something like burnt plastic or wire insulation. Too much power, will give this result.
2. No sound ... separated voice coil wire or tinsel lead pulled away from VC. Mechanical failure, as too much input power, excess bass boost or Xmax exceeded due to wrong enclosure specs.
3. Buzzing or rattling sounds, (while sub is playing at moderate to loud SPL)... Loose dust cap, spider, VC separated from cone or surround is separating from cone. This is usually caused by fatigue, aging woofer or poor assembly at factory. User repairs are often possible here. A little Super Glue or contact cement or epoxy, will do the trick here. Sometimes, excess bass boost will create these issues too. Often, sub is going past X-max here too.
4. Seized cone, some sound, but very poor bass output, the cone will not move manually or with power applied... In this case, the VC has jumped the gap, and is locked into a frozen position, outside the gap. You may try manually re-inserting the cone/VC, back into the magnetic gap. This is caused by excess bass boost, wrong box specs and over excursion (Xmax exceeded) When this happens, you may have to repair or replace the sub, as the VC may have been damaged and scrapes the pole piece.
Swez
If it ain't broke, you're not trying hard enough
LC1 on 08/26/2004 20:33:33
It plays fine, its just when I took the sub out of the box it sounded like there was somthing rattleing inside and when I push in the center of the cone it make a scrapping/scratching sound. I spoke to a guy that I know who owns a car audio shop and he has no clue what the problem is. When I first told him what was wrong he said bunrt VC but then we hooked it up and it payed fine and the scraping stopped. Then we took it out of the box again and there was no more scrapping or ratteling. He said just keep an eye on it and that I could send it to Alpine since I've only had it for about 3-4 months if I wanted to.
Jay
swez on 08/27/2004 09:07:52
Think it woul be a good idea to sent it back to Alpine for warrantee repairs/replacement. It won't heal on its own. This sounds like some kind of internal sub problem. One you cannot see or fix until the sub is dismantled.
If I had a educated guess, part of the bobbin has come loose (delamination) below the spider. It is out of alignment with the pole piece, hense the loose rattle noise and some scraping.
Swez
Anybody have any ideas on what this could be or is this not a big deal. I doubt this is normal, never heard anybodys speakers make this noise before.
Thanks in advance,
Jay
PS its an Alpine SWR-1241D running off a JBL 300.1
Replies (7)
P0werLifter on 08/26/2004 02:23:26
This is not my area of expertise but to me it sounds like the speaker cone has seperated from the spider or something with the voice coils. Im not positive tho, Swez and some of the others are more versed in this area...check on Chrono's post about "ED vs ADIRE" theres some info on there that could help you out.
-Jason
uochronos on 08/26/2004 02:35:25
yes definatly read what swez said in my post it well help you a bit here... sounds like the voie coil is rubbing or something similar... i cant say that this is good anytime the sub makes a scratching sound at little movement... if its still under warranty i suggest sending it in.
Munchiesyumm on 08/26/2004 11:55:06
I will suggest that you play with the LP filter. (low pass filter) This will change the sound of the sub making it more punchy or more bassy.
I know JBL amplifier's are a little more difficult to set sense you're kinda blind where you're setting the nob. They don't mark 50hz, 70hz ect.. When you're setting it keep the volume semi low but loud enough to listen for the distortion to clear. Once you find where you like it turn it up to the desired loudness and listen for any distorion. Check both from close up and farther away and inside the car. This is how you get that perfect bass notes u like. I'll let you be the judge on the bass boost 3-6db is okay depending on the application.
have a great day!
I just fixed a problem like this the other day in about 6 minutes. Remember that a sub that is not properly tuned will eventually blow.
As for pushing down on the cone you should hear some noise from the cone moving up and down but this is normal. You'll know the difference between a blown sub and a good sub, the blown one will push down really easily. Trust me on this when a sub blows you'll find out reall quick!
compvr15s on 08/26/2004 18:41:37
it definitly sounds like an issue with the voice coil. nothing else inside the sub should make a scratching sound, did you make sure you pushed strait down on the cone, if you kind of force it to one side this will happen.... when pushin down the sub should feel normal no tension, if the VC is cooked you will definitly know, in all the solos that i fried, once the cone quit moving it too tremendous force to realese the sub... dont know if this is because it melted to something or what... i really doubt your sub is blown, you would know by a destinctive smell.. id imagine it just seperated or somehting along those lines. have you tried runnin the sub yet??
swez on 08/26/2004 19:53:44
Here's how to diagnose a blown/damaged woofer:
1. Some sound, but lots of rubbing scraping is heard. Voice coil was burned or charred... Can hear scratching/rubbing sounds, when you manually pump the cone, with no power to sub. You may even be able to smell something like burnt plastic or wire insulation. Too much power, will give this result.
2. No sound ... separated voice coil wire or tinsel lead pulled away from VC. Mechanical failure, as too much input power, excess bass boost or Xmax exceeded due to wrong enclosure specs.
3. Buzzing or rattling sounds, (while sub is playing at moderate to loud SPL)... Loose dust cap, spider, VC separated from cone or surround is separating from cone. This is usually caused by fatigue, aging woofer or poor assembly at factory. User repairs are often possible here. A little Super Glue or contact cement or epoxy, will do the trick here. Sometimes, excess bass boost will create these issues too. Often, sub is going past X-max here too.
4. Seized cone, some sound, but very poor bass output, the cone will not move manually or with power applied... In this case, the VC has jumped the gap, and is locked into a frozen position, outside the gap. You may try manually re-inserting the cone/VC, back into the magnetic gap. This is caused by excess bass boost, wrong box specs and over excursion (Xmax exceeded) When this happens, you may have to repair or replace the sub, as the VC may have been damaged and scrapes the pole piece.
Swez
If it ain't broke, you're not trying hard enough
LC1 on 08/26/2004 20:33:33
It plays fine, its just when I took the sub out of the box it sounded like there was somthing rattleing inside and when I push in the center of the cone it make a scrapping/scratching sound. I spoke to a guy that I know who owns a car audio shop and he has no clue what the problem is. When I first told him what was wrong he said bunrt VC but then we hooked it up and it payed fine and the scraping stopped. Then we took it out of the box again and there was no more scrapping or ratteling. He said just keep an eye on it and that I could send it to Alpine since I've only had it for about 3-4 months if I wanted to.
Jay
swez on 08/27/2004 09:07:52
Think it woul be a good idea to sent it back to Alpine for warrantee repairs/replacement. It won't heal on its own. This sounds like some kind of internal sub problem. One you cannot see or fix until the sub is dismantled.
If I had a educated guess, part of the bobbin has come loose (delamination) below the spider. It is out of alignment with the pole piece, hense the loose rattle noise and some scraping.
Swez
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