Bri3L6

ok im pretty bad with audio and was hoping to get an opinion other then best buy's ......one of my subs blew out and its the second time ive had this happen ( same type of sub with the same set up)

i got two Infinity Reference Series 1050Ws (250 w RMS/ 800w peak, 4 Ohms)
powered by a Audiobahn A4002T amp (2 channel, 100x2 Watts RMS, 400 Watt Peak)

the sub is def blown and the connections are fine...i thought maybe the amp was to powerfull for the sub but then why is the other one still kicking ? the amp overheated a lot and maybe that put some wear and tear on the sub but im trying to figure out if this is just a bad set up.

any feedback is much appreciated

Telexen

I'm certainly not going to claim to be an expert...but if your amp only provides 100W per channel, I think it's likely you have been constantly clipping the amp, or overloading it. This wreaks havoc on the speakers.

Socket7

You have set your gains and crossovers incorrectly. If you've turned your gains all the way up in an attempt to make your system "louder" (gains don't work that way) chances are you've pushed your amp into clipping. Instead of a nice sin wave coming out of the amp, you're getting a square wave. This prevents the sub from moving as much as it should for the amount of current going through it, causing the voice coil to overheat and fail (Which could even short out in the process, and damage your amp too).

Setting your crossovers incorrectly can let the wrong frequencies get to your sub, and that can also cause speaker damage, or just really gross, boomy, distorted bass.

Do you have the Bose system, or the stock stereo? Also, where are you pulling the signal for the sub from, and what kind of line output converter are you using?

Also, Read this http://www.bcae1.com/2ltlpwr.htm to truly understand why you're blowing your speakers.

Bri3L6

Socket7, i never messed with my gains there all the way low...its a stock stereo and im not sure how to answer the other two questions ....

I had this set up for a year and it worked perfectly..then it blew..got a replacement..worked for another year and it blew

are these subs just not a good match to begin with for the amp?

Socket7

The sub's should work fine with the amp. The RMS/peak rating for the subs are both above the RMS/peak for the amp, so it's not a matter of too much power.

The amp overheating is a sign that there's something wrong, but it's hard to say what without looking at the system. Could be a bad ground maybe. Could be turning bass boost up. Could be a faulty Line output converter. Even with the gains low, you could still have a clipped input signal.

Can you take it back to the shop that installed it and have them look at it?

Bri3L6

ok well im glad that the subs should work fine...i would of had to go through the trouble of selling the sub that does work and buying two different brands ....the shop that installed it was best buy and the guy there did **** when i brought it to him to look at ...he just told me the setup was bad and the amp was too powerfull for the subs

im gonna recheck the wiring myself make sure the bassboost is as low as it goes and try to get a replacment sub from infiniti

thanks for the help...i got more info from you in two posts then i did from a 30 minute trip to best buy lol

firebirdude

iTrader: (3)

Other than making sure your gain, bass boost, crossovers are set correctly.... look at the settings on your headunit as well. Got the bass set to 0 when you set the gain and then crank it to +6 while you're driving? That's gonna add to any clipping issue.

Ensure the subs are wired together in series, and then bridge the amp.

It is possible your friends at Best Buy wired them in parallel for a final 2 ohm load to a bridged amp. This would cause frequent over heating. If you discover this is the case, I would take my car back to Best Buy and demand they replace the blown sub at no charge. That is a broken rule of thumb that any installer should know. Know exactly what you're talking about when you go in there, and ask to speak to a manager.

Socket7

Best buy not doing **** for you when something goes wrong is one of the big reasons I advocate having your work done at a reputable car audio shop. A bit more expensive? sure, but they'll stand by their install.

I'd make sure that I have 2 sub's of the same model. I don't personally believe in mixing and matching subs that will be receiving the same signal. A pair of 2 ohm 10" woofers wired in series would give you the right impedance you need to run in bridged mode.

You have a 2 channel amp though, so you could also take 2 4 ohm speakers and wire one to each channel, rather then running bridged.

Bri3L6

yeah i was kinda reluctant to take it to best buy in the first place ...

anyway, thanks for the help ..im gonna brush up on my wiring and see how my connections were done ...so im guessing the ideal way is to be wired in a series?
Im probablly just gonna replace the infiniti sub (With the same one, I wouldnt wanna mix and match either)

oh this mite be a dumb question but if the amp's been clipping and the wiring is then fixed ..is the amp still gonna be damaged and continue to clip ?

firebirdude

iTrader: (3)

Ideally, you would have a 4 ohm final load for a bridged 2-channel amp. However, he stated that he has the 4ohm single voice coil version of the Infinity Reference line. A 4-ohm final load is impossible with two subwoofers. This is EXACTLY what upsets me with Best Buy. Their pure ignorance on the subject has caused this customer to either have an overheating amp @ 2ohms or an amp that only does half its rated power @ 8 ohms. If they do not stock the correct version of subwoofer to match this amp, then they should have sold him a different amp entirely.

If you run two subwoofers each off their own channel on a 2-channel amp, they are getting slightly different signals. One playing the left channel and the other playing the right channel. If your headunit has a dedicated subwoofer RCA out, this is obviously not a problem. But in the 8, I'm sure they used a LOC tapped off the rear speakers. Wiring the subwoofers together and then bridging the two channels together solves this. Not a huge deal, but truth none the less. Same power out, so why not.

Bri3L6, ideally you want the REF1052W version of the subs you have. Exactly the same except they are DUAL 4 ohm. Note this difference on Infinity's page between the REF1052W and REF1050W. They are exactly the same price and are specifically made to assist the user in matching up the amp they're using to get full power out. Best Buy botched the match up. Plain and simple. This page can help you visualize some different wiring schemes.

Socket7

If the amp doesn't sound like garbage, it's fine.

http://www.bcae1.com/spkrmlti.htm has all the info you could ever want on wiring speakers in parallel or series.