Smells like burning plastic !!!

[Fishguy 10+ year member]

Hay all, I was listening to my radio on the way to work this morning and had it turned up pretty good and after about 15 min I could smell something like plastic was burning. Turned the sounds down a bit and after getting off the freeway I pulled over to check my amps and wires. They where all good but after going to the rear passenger seat of my crew cab (side of my boxes port ) I could get whiffs of that smell again. Traced it and it smells like it’s coming from inside the boxes port so I assume ( ya I know LOL ) that it’s the voice coils on my 10” L7. Question is, is this normal break in as the L7 is only about a month old and really hasn’t been given that many amps until the past couple days or do I need to turn the gain down a bit more on the sub amp ( Kenwood KAC-9152D wired at 2ohms (900w) and pushing the single 10” L7 that’s wired @ 2ohms ?? Also, the amps gain is only at about 2/3 too.

Any info appreciated,

B

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[skylineTT 10+ year member]

yeah prolly just excess glue melting and ish. just take it kinda easy for a week more and then hit it hard.

 

[Buck 5,000+ posts]

The gains don't work like a volume knob. I would turn them down a bit. I bet your clipping it a little bit.

 

[Fishguy 10+ year member]

Thanks for the feedback guys and I know the gain isn't like a volume knob. I'm not turning up and down the gains while driving. Amp gain was set and left at 2/3 max and I was just stating what it was set at when the problems occured. The amp wired at 2ohms at full gain should be pushing around 900w but the 10' L7 can only handle 600w RMS so thats why the amp was pre set 2/3 of the max gain. Figuered that setting would give the sub around 600w without toasting it.

 

[bubbagumper6 5,000+ posts]

Thanks for the feedback guys and I know the gain isn't like a volume knob. I'm not turning up and down the gains while driving. Amp gain was set and left at 2/3 max and I was just stating what it was set at when the problems occured. The amp wired at 2ohms at full gain should be pushing around 900w but the 10' L7 can only handle 600w RMS so thats why the amp was pre set 2/3 of the max gain. Figuered that setting would give the sub around 600w without toasting it.

You have no idea how a gain knob works. Turning it to max, does NOT mean your setting it to max power, nor does setting it at 2/3 to get "2/3 of the amps power". You could be clipping the hell out of it. Learn how to set it properly before you destroy something.

http://mobile.jlaudio.com/support_pages.php?page_id=143

 

[Fishguy 10+ year member]

"You have no idea how a gain knob works"

No I dont. Just going off what I've been told and thats why I'm here trying to figure out whats up. If I new what was going on I wouldn't need to come here LOL!! Thanks for the link but I dont have the meter. I'll have to get my electrical buddy to help me out.

 

[DBfan187 5,000+ posts]

Were you listening to Cher?

 

[skylineTT 10+ year member]

basically just turn the volume up as loud as you will listen to it, then turn the gain up until it starts to distort.. then back it off a little.

 

[Fishguy 10+ year member]

"Were you listening to Cher? "

You serious ??? Hope not LOL!!! If it maters I was actualy listening to Power Supply's "Pure Silicon".

Skyline TT , thanks for the info. Thats basicly how we tried to dial it in the first time but obviously somethings not right. I'll give it another go around and see what happens. If it doesn't work out I'll grab a meter and get to work.

 

[Fishguy 10+ year member]

Couldn't get a meter so last night I went and zeroed out all the HU settings and set the HU volume to ¾ with both amp gains backed off and then I adjusted the gains up by ear and then backed them off a bit after starting to hear a bit of distortion. I’m basically just a bit lower on my gain setting. Sounds loud and clean like before. Used Beat Dominator “Can you here Me” and ran it with HU volume at 21, sub 15 , bass 1, treble 2 . F540 gain set at .5 (between ½ and ¾) and the 9152D is set just past 1 (between ½ and ¾’s) and the sound is clean and loud. No smell. Now I need to play “Pure Silicon” again as it seems the sub only gets hot on that song (forgot to mention that in my first post) with the HU settings basically the same as above.

Appreciate the feedback and help,

 

[Fishguy 10+ year member]

Still not confident about pushing the sub so about an hr ago I pulled the 10" L7 out of its speaker box just to make sure the wires where hooked up to the right termnals . Everything looked good but I did notice that the + power wire run from the amp to the sub went to the + of VC #1 and then jumped from the actual termnal of VC#1 to the + terminal on VC#2 (4ohm DVC sub ran at 2ohms). Same thing with the - wires. Is it possible that the first VC was getting more power and therfor getting hotter than the second VC ?? Would it be better to run the + wire off the amp to inside of the box and then split the wires and run equal lengths of wire to the + of #1VC and #2 VC with each VC having it's own + wire run to it rather than having one jumped off another terminal??. Same thing on the - terminals. Any info appreciated.

 

[csu87 10+ year member]

that wont make a difference. just take it easy on the sub and youll be fine. if i was you, id head to harbor frieght and pick up a $5 meter so you can set the gains better

 

[Fishguy 10+ year member]

Thanks for the info. Just getting off work and there's a harbor frieght down the street so I'll pick a meter up on the way home and dial in the gains. I'm tired of dicking around with this, I should have just got the meter to begin with. Lesson learned !!!!

 

[Fishguy 10+ year member]

O.K got the meter on the way home yesterday. Now how do I figuere out my target volt setting for the sub amp ?? Amp is bridged to run at 900w X 1 @ 2ohm. Can anyone help me with the math to come up with my target volt reading ??

 

[Fishguy 10+ year member]

O.k did a little more searching and think I might have figuered out the formula. Sorry for being retarded but math and electrical are not my thing. Anyway 900w X 2 = 1800 divided by the square root = 42.42 look right ??