BTL problems continue

[tehboss 0]

I have had my 12" BTL for over five months now. Around 4 months ago, i started hearing a poping noise on certain high notes. My first thought was that the box it is installed in caused the sub to reach its mechanical limits. The enclosure is 3 cubes after displacement at 34 hz. I know that this box is over the recommended specs, but i am only giving the sub 1000 watts from an Alpine PDX 1.1000. The sub is fully loaded and i have never heard any clipping out of the amp. When i noticed the popiing noise, I turned my amp gain down to around an eighth of a turn from zero. This gave me very little bass, but it kept the sub from poping so i was satisfied until i could find a solution.

Well two weeks ago i turned the gain back up to (3/8) from zero to find the gut wrenching bass that i love. The poping noise was less noticeable than before so i left the gain turned up. Yesterday, i saw that the foam surround was starting to break up. My disappointment was matched today when i turned my stereo on low to hear the sub give one big pop and then discontinued to play until i turned it down all the way and slowly raised the volume or restarted the amp. So after 5 months of having the BTL (and only around one month of actually playing it at high volumes), I am left a $500 bill from my savings and nothing to show for it.

I am considering getting a recone but i have no idea if it will even fix the problem. Also, I would have to send my sub in because i have no idea how to do it myself and would probably waste more money messing it up. If i get it reconed, i think that i am going to buy a new 18" basket and rubber seal to convert it to an 18" sub. I know that FI is really busy right now, and i am still just mind boggled that i pushed this sub to its limits on 1k watts.

Will a recone even fix my sub? The financial burden of this sub is starting to hurt. I don't want to put more money into it if it wont be fixed. Also, any ideas of how it happened? I am curious to see if anyone else has ever had something similar happen.

Thanks in advance,

Andrew

Edited May 2, 2010 by tehboss

[Argent Audio 54]

It sounds like it could be a connection issue due to the fact that it will played after the pop if you slowly raised the volume.

Andrew

[shizzzon 461]

pull it out of the box and see if the spider has come unglued

[tehboss 0]

I have some Videos that I took earlier today. Ill post them as soon as they upload. Maybe they will help.

[Kanaworm$ 292]

How did you set the gains on your amp?

Edited May 3, 2010 by OldSkool_08

[imhungnurnot 9]

What size box do you have the BTL in? Tuning? Also how did you set the gains on your amp?

Try using your eyes to read the original post...

[Kanaworm$ 292]

What size box do you have the BTL in? Tuning? Also how did you set the gains on your amp?

Try using your eyes to read the original post...

my bad! I guess I will edit my post so you don't get any more sand in your vag!

[tehboss 0]

This one has the poping noise on the high note and the big pop that stops the sub

[Kanaworm$ 292]

By the way your vid sounds, it may be the tinsel leads broke at the voice coil. Does it work at all after the last pop?

[NDMstang65 403]

Couple issues here...1) box is too big, stay within the guidelines that we say to stay within...2) Subsonic filter on that amplifier if you turned it on will still cause you issues unless your box is tuned to 27Hz.

The subsonic filter if it is on is set at 25Hz...at 12dB/octave.

Which is completely useless...you must have an amp that has an adjustable subsonic filter that is set 2-3Hz below the port tuning frequency..otherwise that's what happens.

Boils down to over excursion, the surround snaps and the spiders pop like potato chips. It's like taking a brand new car off of the dealership lot..hopping on the interstate with the cruise control on and driving it straight into a wall...the dealership isn't going to warranty it because you drove it into the wall . Speakers are stupid, they do exactly what you tell them to do.

You can fix it with a recone..but if you don't get an external adjustable subsonic filter or a different amplifier you'll do it again in a couple weeks time. I've seen it happen many times..and it's always the exact same issue , you also need to shrink your box as well. I've ran in excess of 2000 watts per sub with music and never had an issue...this goes to show if you do not have things set up properly you will have nothing but problems.

Hope this helps.

[tyoung515 7]

what nick has said is very true, order a recone and either shrink the box or change up the ssf filter, i run a sa-12 in a customers 07 rango on a sax-125.2 (round 450-500wrms @4ohm) and has had no problems BUT i have the box tuned to 30hz and the ssf up to about 27hz, if i where to drop the ssf what happed to your btl would likely happen to the sa. i have not had my hands on a btl yet but i am starting a box for 2 18" 14cf@33hz on a single saz3500 pure daily ground pounder for a customer. order the recone and have fun bro, thats a great sub you have!

[tehboss 0]

The only problem I have with the amp is that the ssf is not adjustable. The ssf has three settings: 0,15, or 30. I just don't understand how I am hurting the sub with low notes if the box is tuned 4 hz above my amps setting.

[Kanaworm$ 292]

To large of an enclosure limits the mechanical ability of the sub, decreasing power handling. Fixed settings on the SSF filter hinder the function if the box is tuned lower than the SSF filter setting.

See if you can add material to your exisitng enclosure to take up space. Try raising your tuning above 30 hz.

[glasscitysounds 0]

...you must have an amp that has an adjustable subsonic filter that is set 2-3Hz below the port tuning frequency

i disagree it depends on the ripple of the box

it sounds to me that you have the coils ran in series and there is a brake somewhere in the sub

the box being only .5 cu ft to big with only half power going to the sub should be fine

are you sure its not the amp?

[johnecon2001 82]

...you must have an amp that has an adjustable subsonic filter that is set 2-3Hz below the port tuning frequency

i disagree it depends on the ripple of the box

it sounds to me that you have the coils ran in series and there is a brake somewhere in the sub

the box being only .5 cu ft to big with only half power going to the sub should be fine

are you sure its not the amp?

You just disagreed with everyone in the thread.

You're not correct bud.

[NDMstang65 403]

...you must have an amp that has an adjustable subsonic filter that is set 2-3Hz below the port tuning frequency

i disagree it depends on the ripple of the box

it sounds to me that you have the coils ran in series and there is a brake somewhere in the sub

the box being only .5 cu ft to big with only half power going to the sub should be fine

are you sure its not the amp?

Wrong...

Because once you play below the resonant tuning frequency of the tuning of the port the port is nothing but a gaping hole in the enclosure...causing the sub to have full power in a "Free Air" environment. The SSF with a steeper 18db/octave slope rolls things off faster and helps keeping this from happening. 1000 watts free air is more then enough to kill a BTL...it has enough coil in it to sling the parts completely out of the gap.

Box is too big, Amp subsonic filter with a very shallow (12db/octave) slope does not roll things off fast enough...and that's what happens. The sub does exactly what you tell it to do and it commits suicide. Box is too big, subsonic filter is not adjustable...

Like I said, you can fix it with a recone...if you do not get a different amp or an adjustable subsonic filter in line it is just like driving your brand new car into a wall. You are going to do it again and be right back here with the same problems forking out money that you shouldn't have had to fork out in the first place. I don't want speakers to break...the last thing I want is a returned product, I never want to see them again once they leave the shipping dock. But things like this happen if it isn't set up right.

-Nick

[KU40 173]

To large of an enclosure limits the mechanical ability of the sub, decreasing power handling. Fixed settings on the SSF filter hinder the function if the box is tuned lower than the SSF filter setting.

See if you can add material to your exisitng enclosure to take up space. Try raising your tuning above 30 hz.

A large enclosure doesn't limit the mechanical ability of the sub, it just reduces the mechanical power handling ability of the sub. The sub can still move the same amount in any box.

[tehboss 0]

Ok, if I send in my sub in FI after purchasing a recone with a new 18" basket, what else will I have to pay to change it over from the 12" to an 18"? I'm thinking about the new packaging and larger seal. Also, how difficult would the change be for someone who has never performed a recone before (I could save over $100 in shipping)

[glasscitysounds 0]

obviously the sub warranty is void when its installed in a box size thats not recommended. i wold pay extra and move to a 18'' if i was you. and my box would be at 30 hz

if a box has a low ripple, it has a flatter response! i dint say he wasn't play under the f3

[Kanaworm$ 292]

To large of an enclosure limits the mechanical ability of the sub, decreasing power handling. Fixed settings on the SSF filter hinder the function if the box is tuned lower than the SSF filter setting.

See if you can add material to your exisitng enclosure to take up space. Try raising your tuning above 30 hz.

A large enclosure doesn't limit the mechanical ability of the sub, it just reduces the mechanical power handling ability of the sub. The sub can still move the same amount in any box.

Thanks for the clarification .... It's what I meant to say, just didn't type out that way.

[wutang512 3]

ok so what would be the most logical thing to do if a person doesnt have a adjustable subsonic filter on their but doesnt have enough money for a new amp?

Cause i have a fixed subsonic filter at 15hz but my box is tuned to 33hz

[Kanaworm$ 292]

ok so what would be the most logical thing to do if a person doesnt have a adjustable subsonic filter on their but doesnt have enough money for a new amp?

Cause i have a fixed subsonic filter at 15hz but my box is tuned to 33hz

What amp?

[Typicaljawaiian 3]

Equalizer, right?

[wutang512 3]

ok so what would be the most logical thing to do if a person doesnt have a adjustable subsonic filter on their but doesnt have enough money for a new amp?

Cause i have a fixed subsonic filter at 15hz but my box is tuned to 33hz

What amp?

its a alpine mrp-1000

[slim2fattycake 85]

sealed box, turn volume down, or just listen to what you're playing and don't play low shit.