Bought 2 RE audio 18 SX's....... and....

[knowledgestick 10+ year member]

Yes, in series... //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif


OP I'm sorry but you completely FAIL at car audio.

Some of you guys might think an amp setting caused this.. but I doubt it.. even with gain and bass boost maxed and that amp clipping hard it shouldn't take those subs out.. and if it did I'd expect to see a damaged coil, not a cracked dust cap..

If you are going to blame the box it should be because the box is way too small.. not necasarilly because it's sealed.. the increased Q of such a small box will certainly put more pressure on the cap - but it still shouldn't have cracked... that coupled with the fact that the other cap looks like it started to melt tells me that RE should be using caps that are much thicker...

I don't want to hate on parts from china, just really cheap parts from china and dust caps that belong on a 250watt woofer, not a 1000 watt one...

i have no idea why you decide to attack me when i have made it clear i know nothing about car audio and it was futurehsop that handled this hole installation, the first subwoofer i put it in my self i mearly copyed their wiring from the last subs i had that where d4, then when they put them in they said they where at 2ohms each so w/e.

Also i just spoke with a guy named mark from RE audio hes sending me 3 dustcaps and the glue to fix them with, he is sure that futureshop dropped somthing on them to start the crack so i dont know what to think now.

He said it was just gross incompetence for them not to adjust the gain accordingly to the new subwoofers, aswell as the box being sealed, plus probably somthing being dropped on them but he cant be sure but he is sure of the above 2 as i told him about them saying sealed would be fine, and that they never touched the gain settings to propperly adjust for the new subwoofers

 

[knowledgestick 10+ year member]

d4 will provide a 2ohm load in parallell not in series, sorry.

This is how both subwoofers are wired up, with indivudiual speakwire, then on the amplifier it is wired up like this

-- ++ one end of the speaker wire for each woofer goes from 1 negative, to 1 posative.

i do not know what the resulting ohm load is, i am just taking futureshops word until i can afford a dmm metre this weekend. But it is suposed to be 2ohm.

 

[Bassman999 10+ year member]

Most of the guys on these forums are either installers or just plain know a lot about car audio. While I hope nobody is trying to attack you just to do it, I still want you to enjoy your new subs. When I was young I didnt know shit about car audio either. I read everything I could find about car audio, I constantly went to shops to bug them and ask qestions. My knowledge grew. I started installing my own stuff after that. Before I knew it everyone around me was like Steve is the Bassman he knows everyhting. Thats when I started installing professionally. What I am trying to say is learn from all this. Every decision you make from here should be based on what you learned so far. Ive learned from reading this that "futureshop" is not working in your best interest, if not plain neglegent and incompetent.

Sorry for rambling. Go to the store and buy a generic Multimeter. Set it to ohms. With your stereo off measure the impedance (ohm load) at the amp. One probe to one of the + other probe to one of the -. Actual impedance and that listed from mfg will differ. You should see either over 3 ohms or around or under 1 ohm. This way you dont have to depend on the shop to tell you how they are hooked up. If you see 1 ohm or less turn the bass boost down and the head unit bass down. If you see 3-4 ohms then I would suggest you have a different shop port your box and still turn the bass boost down. Bass boost is almost always bad.

 

[Bassman999 10+ year member]

Ported boxes rsult in less cone movement around the tuning frequency and less back pressure behind the cone. Always use ported boxes with a sub sonic filter to block frequencies below box tuning to prevent over excursion. With this said maybe the se's are cracking caps from pressure behind the cone and cone flex at high excursion. They were designed for ported enclosures.

 

[knowledgestick 10+ year member]

Most of the guys on these forums are either installers or just plain know a lot about car audio. While I hope nobody is trying to attack you just to do it, I still want you to enjoy your new subs. When I was young I didnt know shit about car audio either. I read everything I could find about car audio, I constantly went to shops to bug them and ask qestions. My knowledge grew. I started installing my own stuff after that. Before I knew it everyone around me was like Steve is the Bassman he knows everyhting. Thats when I started installing professionally. What I am trying to say is learn from all this. Every decision you make from here should be based on what you learned so far. Ive learned from reading this that "futureshop" is not working in your best interest, if not plain neglegent and incompetent.
Sorry for rambling. Go to the store and buy a generic Multimeter. Set it to ohms. With your stereo off measure the impedance (ohm load) at the amp. One probe to one of the + other probe to one of the -. Actual impedance and that listed from mfg will differ. You should see either over 3 ohms or around or under 1 ohm. This way you dont have to depend on the shop to tell you how they are hooked up. If you see 1 ohm or less turn the bass boost down and the head unit bass down. If you see 3-4 ohms then I would suggest you have a different shop port your box and still turn the bass boost down. Bass boost is almost always bad.

Thanks for that post man... i useda be into car audio and i knew a bit about it but i just dropped out of it then got back in when i got those MA audio subs.. then got thease replcaements, but yeah i hear what you are saying for sure. the mark guy explained alot to me about setting the gain propperly, etc. I will deffinatly learn from this and likely handle anything i do in the future myself, although im a bit nervous about adding a 2nd battery into the trunk lol

Would you recommend porting the box regardless ? i dont want to have to throw away the fibreglass part of the box //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif Hopefully i can make use of it.

Thanks a bunch for telling me about the metre, i will get one as soon as i get some funds today

 

[Bassman999 10+ year member]

Ported enclosures tend tobe louder than sealed enclosures too (when done properly)

 

[knowledgestick 10+ year member]

Ported boxes rsult in less cone movement around the tuning frequency and less back pressure behind the cone. Always use ported boxes with a sub sonic filter to block frequencies below box tuning to prevent over excursion. With this said maybe the se's are cracking caps from pressure behind the cone and cone flex at high excursion. They were designed for ported enclosures.

This is what i am thinking, it even says it in the manual and like i said i pointed it out to my installer and he pretty much persuaded me to stay with a sealed box.

even though it is fairly large sealed box it still isnt enough, thease things need ported i asked him because i had suspisons.

**** i wish there was a shop with installers like you around here, we dont have a single store dedicated to car audio install's all futureshops, visions crap.

 

[Bassman999 10+ year member]

you first have to determine the cubic airspace in the box. I dont know how much space you have to add ports. If you can use power tools I cn tell you what to do yourself

 

[knowledgestick 10+ year member]

you first have to determine the cubic airspace in the box. I dont know how much space you have to add ports. If you can use power tools I cn tell you what to do yourself

the box is over 10 cubic feet its deffinatly a deciant sized box, i just need to know how to port/tune it propperly.

i went out and i adjusted the gain propperly like instructed by the R-E audio guy, they sound x10 better and the crack didnt get any bigger, i was as fast as possible so i didnt have it going too long. But i think it was multiple things that contributed to the overheating/cracking.

its all a learning lesson, and atleast im getting replacement caps out of the deal.

 

[Haunz 10+ year member]

Ported boxes rsult in less cone movement around the tuning frequency and less back pressure behind the cone.

Ported boxes will net less excursion around tuning, but SPL levels inside and outside the box will peak.. hence, at tuning you will have the most backpressure...

Above tuning a ported box acts the same way a sealed box does.. so as I said, if you want to blame the box then lay the blame on it being too small.. those subs need 5-6 cubes+ each to work properly..

As far as the dust cap it's possible futureshop damaged it, but that dosen't explain the one that bubbled out either..

 

[Haunz 10+ year member]

the box is over 10 cubic feet its deffinatly a deciant sized box, i just need to know how to port/tune it propperly.

If the box is over 10 cubic feet then it shouldn't be a problem... but didn't you say it was around 5 cubic feet earlier ? Which is it ?

 

[Bassman999 10+ year member]

If the box is over 10 cubic feet then it shouldn't be a problem... but didn't you say it was around 5 cubic feet earlier ? Which is it ?

I guess he meant 5 ft^3 per sub.

 

[Bassman999 10+ year member]

Ported boxes will net less excursion around tuning, but SPL levels inside and outside the box will peak.. hence, at tuning you will have the most backpressure...
Above tuning a ported box acts the same way a sealed box does.. so as I said, if you want to blame the box then lay the blame on it being too small.. those subs need 5-6 cubes+ each to work properly..

As far as the dust cap it's possible futureshop damaged it, but that dosen't explain the one that bubbled out either..

I also think he was clipping his amp and heating up coils

 

[knowledgestick 10+ year member]

I also think he was clipping his amp and heating up coils

yeah, its around 5 per sub, if not more. there is a video posted with me looking and showing the inside of it, my car is a monster the trunk is huge and the box is the hole trunk.

I tuned the gain and the center of the subwoofers are still getting slightly warm to the touch, so i dont know what is going on. im not going to touch them anymore until i get the metre to see what ohm they are at.

You want to have the gain nearly off if possible correct ? this is what i have taken from what i have read/heard so far.

 

[knowledgestick 10+ year member]

i know people are going to call me retarded for this but im just trying to get this all soarted.

i was adjusting the gain, and when it is at a very low level the system is EXTREMELY quiet the gain has to be over half for there to be any bump behind the subwoofers, its like the amp isnt giving out natural power or somthing, now this is a retarded quesiton probably but i duno what else to ask.

is there anyway futureshop could have not put the fuses in the amp when they installed it origonally ? and thats why ive always had to have the gain and bass boost up ? i dont even think an amp can start up without its fusing but i thought id ask anyways because they have already done some pretty stupid stuff

But yeah, without any bassboost or gain the system is extremely quiet, even at high-levels.