Blew 2 L7s within a hour

[Uptown_Kdot]

I need some help I had 2 dual 4ohm L7s hooked up to a autotek 4000.1 amp and I fried both subs. One started smoking 5mins after hooking it up the other one took about a hr. I have 2 more set to hook up but I wanna no what I did wrong before I blow two more.

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[Uptown_Kdot]

I had them wired to 1ohm so the amp was giving them 2000 wards rms was that too much power since they are 750 rms each which comes to 1500

 

[mazdakid 5,000+ posts]

How high is your gain and bass boost? What kind of box are they in?

 

[Uptown_Kdot]

I had the gain set to a lil but below halfway and the bass knob was about 3/4 up. They are in a ported box

 

[blobb454 10+ year member]

It's usually do to improper wiring, set up and or poor quality equipment.

 

[maddog 10+ year member]

are you using aero ports?

 

[pickup1 5,000+ posts]

I had the gain set to a lil but below halfway and the bass knob was about 3/4 up. They are in a ported box

Bass knob or bass boost?

 

[72Impala 10+ year member]

Turn your bass boost all the way down, take your bass knob and throw it in the garbage and don't ever use one again. You are sending a distorted signal to the subs and frying them. Most bass knobs adjust the bass boost, they are garbage. Lastly, have someone who knows what they are doing set your gains properly

 

[Uptown_Kdot]

are you using aero ports?

I'm not sure what an aero port is could you elaborate please

 

[Uptown_Kdot]

Turn your bass boost all the way down, take your bass knob and throw it in the garbage and don't ever use one again. You are sending a distorted signal to the subs and frying them. Most bass knobs adjust the bass boost, they are garbage. Lastly, have someone who knows what they are doing set your gains properly

Ok will do I kinda figured it had something to do with that bass knob and yea I'll take it to an audio shop in the morning to let themset the amp up

 

[NASTY08IMPALA 5,000+ posts]

well read up on setting.gains properly amd.do not.touch bass boost ..also L7s ***** and cannot take much power over rms well.. esp a dirty clipped signal..dont buy another pair

 

[jrdnhsnbrg 10+ year member]

Turn your bass boost all the way down, take your bass knob and throw it in the garbage and don't ever use one again. You are sending a distorted signal to the subs and frying them. Most bass knobs adjust the bass boost, they are garbage. Lastly, have someone who knows what they are doing set your gains properly

There is nothing wrong with a bass knob if you set the amp correctly. If OP sets his gains with the bass knob plugged in and turned all the way up he will have no problems, other than using a VERY low quality amp that will not do rated power and questionable quality subs. Bass knobs are very useful if set up properly, there was a thread about this recently. I suggest taking a look at it.

 

[2Dcore 10+ year member]

My friend got that beat he blew both in a 5 sec blurb of music, lol. Garbage subs hate them.

 

[72Impala 10+ year member]

There is nothing wrong with a bass knob if you set the amp correctly. If OP sets his gains with the bass knob plugged in and turned all the way up he will have no problems, other than using a VERY low quality amp that will not do rated power and questionable quality subs. Bass knobs are very useful if set up properly, there was a thread about this recently. I suggest taking a look at it.

Only if your bass knob adjusts the GAIN, if your bass knob adjusts the BASS BOOST, then either way it is trash. No matter how you look at it, if your knob is adjusting your bass boost, garbage can. The bass boost is just distortion.

 

[Jeffdachef 5,000+ posts]

i agree with the knob being garbage. Most knobs i come across always induces some form of distortion even if its the volume/gain knob. I always get a cleaner, louder signal without the knob in the system.

OP when you go to the shop, make sure they use an Oscilloscope or an SMD-DD1 to tune your system if possible. Make sure your head unit's equalization is set to flat, Bass is at 0, subwoofer level is at max or close to max, LPF at 80. You could have been clipping the signal with your head unit, or your amp's settings or BOTH. Read up on clipping in detail so you learn how to avoid it. Because 2 L7s is a hefty price tag for a lesson learnt. Also buy better subs then kickers... they are pretty weak in the durability department.