im old school and need some new school help...

[CyCloneTSi]

at the begining of this year i bought a Kicker l7 12" 2ohm dvc run by a Highfonics Brutus running 2400 watts at 1 ohm. Now back in the day ratings were acurate but the more i research im finding that this isnt the case anymore so i dont know how accurate my numbers are. my setup is in the trunk of a 03 nissan sentra in a 1.25 cubic foot sealed box running 0 gauge power and ground also have a 3 farad cap on system. here is my dilema, my wife loves it but im a bass head and bought another l7 2ohm dvc. these are wired for a 2ohm load running 300 watts per voice coil. l7 spec says rms is 750. max is 1500 watts. the single subwoofer setup still sounded better and i know why. my question is what amp should i be looking for under 200 bucks. second delima is my first setup did fine as far as power draw on my alternator with the amp at 1ohm load. my previous setup at 2ohms is makiing my headlight flash and completely draining my cap.... with these things in mind to run both l7s: do i run a 2 ohm or .5 ohm load? do i trust advertised specs and try and get close to 750 watts per voice coil?

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[gimling]

uh could you provide us a little more information? so you were running the hifonics brutus at 1ohm which would be 2400 watts RMS 1200 per coil. you added a second woofer and are running at 1600 watts which would be 400 watts per coil. thats a net loss in power and its now dimming?? not really making much sense to me, did you change gain settings when you made this switch?? what was your voltage output on the amp with a 60hz tone?? I am an old schooler myself so i use multimeter and oscope religiously now days. my Guess is that the brutus does no where near 2400 watts, and did u add a second box or a new box all together??

 

[CyCloneTSi]

two seperate sealed boxes. only moved gain to 3/4 from 1/2 for both woofers. i dont want to run the amp at .5ohm so i had to wire both speakers in series parallel, that gave me a 2 ohm load and yep lights dimming at 2 ohm but not 1. totally backwards from how i remember it should be lol. i have to measure voltage from the amp in the next couple days. maybe this will tell me something about whats going on. by the amps specs i should be 1200 watts at 2 ohms / 300 per voice coil which i know is way unpowered. im thinking this may be a reason for the lights dimming? im using a highfonics zrx2400.

i remember when the l7 first came out and i put one in my friend's blazer with a memphis bass 1000 watt at 2 ohm. and it out-pounded many many systems at 122 db's...

im bout to leave class so ill check in and update info later, ty for your input!

 

[kingjd7 10+ year member]

I thought L7 subs hated sealed enclosures...Am I wrong? Wouldn't one in a proper ported enclosure be much louder than two in sealed enclosures? It sounds like the amp, subs, and dimming are the least of the problems of getting a good loud setup.

 

[kingjd7 10+ year member]

Also you should do the big 3 in 0 gauge. neg to block, alt to battery, chassis to block/neg. From what I understand the cap isn't really going to help you at all. Plus I know the SE-R I had had a really weak alt. Whats the amps on the alt you have?

 

[LosIsATool 5,000+ posts]

two seperate sealed boxes. only moved gain to 3/4 from 1/2 for both woofers. i dont want to run the amp at .5ohm so i had to wire both speakers in series parallel, that gave me a 2 ohm load and yep lights dimming at 2 ohm but not 1. totally backwards from how i remember it should be lol. i have to measure voltage from the amp in the next couple days. maybe this will tell me something about whats going on. by the amps specs i should be 1200 watts at 2 ohms / 300 per voice coil which i know is way unpowered. im thinking this may be a reason for the lights dimming? im using a highfonics zrx2400.
i remember when the l7 first came out and i put one in my friend's blazer with a memphis bass 1000 watt at 2 ohm. and it out-pounded many many systems at 122 db's...

im bout to leave class so ill check in and update info later, ty for your input!

Gain is not a power knob. Adding another sub don't mean turn the gain up to make more power, it don't work that way. Buddy 122db is nothing. That's what good stock subs can do

 

[Jeffdachef 5,000+ posts]

two seperate sealed boxes. only moved gain to 3/4 from 1/2 for both woofers. i dont want to run the amp at .5ohm so i had to wire both speakers in series parallel, that gave me a 2 ohm load and yep lights dimming at 2 ohm but not 1. totally backwards from how i remember it should be lol. i have to measure voltage from the amp in the next couple days. maybe this will tell me something about whats going on. by the amps specs i should be 1200 watts at 2 ohms / 300 per voice coil which i know is way unpowered. im thinking this may be a reason for the lights dimming? im using a highfonics zrx2400.
i remember when the l7 first came out and i put one in my friend's blazer with a memphis bass 1000 watt at 2 ohm. and it out-pounded many many systems at 122 db's...

im bout to leave class so ill check in and update info later, ty for your input!

Get rid of those sealed boxes and get a custom ported box for one of them, If you can fit 7-8 gross cubic feet in your vehicle then you might be able to run both of them. You are getting at most 25% of the sub's output potential with those boxes you currently have. You should at least be in the 135 to low 140s range with two L7 12s

Get your electricals upgraded too, those amps are power hogs. Once you have done so, I wouldnt hesitate to wire that amp at .5 ohm but you got to learn to set gains properly and take care of your system.

 

[CyCloneTSi]

honestly i can remember if it was an l7 or l5, 1998ish was a long time ago lol! I do remember the numbers and how impressive it was!

 

[CyCloneTSi]

Thank oyu for the input, ill try upgrading and changing some things around to see what kind of improvements I can get without changing components.

 

[CyCloneTSi]

ok update, i have done 2 of the 3 power wire upgrades simply because i have ran out lol. I replaced the cap with a good size battery and also fond out that my alternator was weak so replaced that too. luckily it was under warranty. I have my amp wired to .5 ohm now as well but the most important thing i found was on the amp wiring kit i bought had stupid gold plated tin eyelit on the battery end and it was so small and thin, so i cut that off and put a real big battery lug on it. My system now runs much more efficiently with very little power drain (lights dimming). I need to find an oscillator and also measure voltage from the amp as well. With all settings on my head unit at 0 and amp gains about 10% its way better than it was in all aspects. I plan on going back to a ported box as well. Thank everyone for their input. I have a friend that has an SPL mic and he is waiting for me to get my gains set properly. with my volume about 2/3 my rear view wont stay put lol. i cant wait to get it tuned. ill let all ya know how it goes.

 

[CSCStang]

ok update, i have done 2 of the 3 power wire upgrades simply because i have ran out lol. I replaced the cap with a good size battery and also fond out that my alternator was weak so replaced that too. luckily it was under warranty. I have my amp wired to .5 ohm now as well but the most important thing i found was on the amp wiring kit i bought had stupid gold plated tin eyelit on the battery end and it was so small and thin, so i cut that off and put a real big battery lug on it. My system now runs much more efficiently with very little power drain (lights dimming). I need to find an oscillator and also measure voltage from the amp as well. With all settings on my head unit at 0 and amp gains about 10% its way better than it was in all aspects. I plan on going back to a ported box as well. Thank everyone for their input. I have a friend that has an SPL mic and he is waiting for me to get my gains set properly. with my volume about 2/3 my rear view wont stay put lol. i cant wait to get it tuned. ill let all ya know how it goes.

If you want a solid custom ported box for those and have the room pm me. I'll hook you up nice man.