Rep Power: 312

hey guys, i've spent the last 2 weeks completely rebuilding my sound system and i want to make sure my sub is really at 2 ohms. I know that i'm prolly being nit picky but I want to make sure. I do have it wired down to 2 ohms, but when I check it with my multimeter it says it's at 2.4, now the sub is in the box and is hooked up to the amp (mainly because i have pulled the whole box out more times than i can count, so i am really sick of it). Is it normal to have the sub at 2.4 ohms instead of 2? If not how or what do i have to do to fix it? thanks guys

 
Rep Power: 0

I've been told to round down when it comes to the ohms.

 
Rep Power: 312

^^ damn, nice response time, any other opinions?

 
Rep Power: 0

2.4 = 2 ohms yep

 
Rep Power: 0

close enough, when the music starts playing the speaker's impedance will change drastically as it reproduces music. If its more than an ohm off, then i would start to worry

 
Rep Power: 312

if it's an ohm difference while it playing or when it's off?

 
Rep Power: 336

ok, your getting the .4 from the resistance of the speaker wires throught the whole loop. the sub is wired at 2 ohms. the speaker wires are giving the rest of the .4 ohm resistance. so if you want less resistance, upgrade the wires your using on your sub and amp. like i used 12 gauge to connect the sub to the amp and got way less resistance than lets say 18 gauge.

 
Rep Power: 312

so use smaller wire? wow i always thought the bigger the better so ididn't get any signal loss, i'm use 8awg right now

 
Rep Power: 336

jeebus! no use bigger. what size wire are you using in each part of your setup? what amp and sub?
ground-
power-
speaker wire-

 
Rep Power: 312

ground - 8awg
power - 4 awg up to the distribution block then about 6 inches of 8 awg
speaker wire for the sub is - 8 awg even in the box.
sub - infinity reference dvc in a 1.75 ft/3 sealed box
amp - bazooka 300 rms @ 2ohms ( yes i know thats the next new thing i am buying lol)

 
Rep Power: 312

now with the infinity, no more crunch (skeet shooting material) and re-caulked ( the woofer takes about 3 seconds to comes back up when i push it in

 
Rep Power: 336

ground should equal power wire...and power wire should be same gauge from battery to amp...and you could do a better amp if you still havent bought one. go online.

 
Rep Power: 336

2 amps for one sub? overkill. but anyway make the ground and power 4 gauge all around

 
Rep Power: 312

yea, amp is next on the shopping list, the ground is going to that bolt that holds the back seats in and i was always told that 8 awg would be enough if it was within 18 inches and this is like 10-11 away?
the other amp is for my surronding speakers btw

 
Rep Power: 336

idk about your car, if you mean 18 inches away from the amp i guess but not 18 from the battery. i c about your second amp. coolness

 
Rep Power: 312

well yea, the power wire is 4 awg straight from the batt to the dist. block ( as you can see) the ground goes under the bar and screws right there, basically in between the seat back and the part you sit on....so should i make the actual speaker wire thinner or thicker? I've got the same wire in the box too, it's 8awg

 
Rep Power: 336

8 is plenty i used 12 guauge for the sub wire and it was plenty. 18 was too small 4 me. now that i think about it 8 is freakin huge for speakers lol.

 
Rep Power: 336

Holy **** dude, 8ga wire for the subs? That's kind of ridiculous, but whatever makes you happy. Whenever I have metered a 2ohm sub it always read 1.8 or less than 2. I have never read anything higher than 2 unless it was a 4 or 8 ohm. When I meter 4 ohm subs it always reads less than 4 but not exactly or more if you know what I'm saying. Kind of strange.

 
Rep Power: 312

I've got 2 15s in my house that i run the same wire to, and thats where i actualloy got the wire from, so it's home audio wire....i wonder if that might have something to do with it?

 
Rep Power: 336

right, when you measure the resistance at the 2 terminals it is less than 2 or 4 or whatever. but when you measure them along the circuit somewhere, the wires add resistance making it a little more than the 2 ohm or 4 ohm of the sub itself. im gonna guess matt measured along the circuit and not at the 2 terminals

 
Rep Power: 336

wire is wire. gauge is the only difference, besides the strand count in each spool in each thread lol

 
Rep Power: 312

yea i did, i was on lunch at work and bored so i check it from the terminals on the amp, so u think if i put a lil smaller wire on there (like 10-12awg) that i'd actually get more power to the sub?

 
Rep Power: 336

i meant the terminals on the SUB not the AMP. if you did it on the amp then its FINE. expect the little extra resistance from the wires and amp itself, since its part of the circuit

 
Rep Power: 312

i figured it was cuz it's still contected, so it sounds like everything is huncky dory then?

 
Rep Power: 336

yea your fine. and not in the hot way either

 
Rep Power: 312

damn it Boris, u got my .....uh "Hopes" all up and everything too.

 
Rep Power: 0

dont worry, 8 guage is a little absurd, but whatever makes you happy. As long as your sub is close to the stated resistance, your fine. For short runs of wire, the size isnt that important. When i was up at mobile dynamics they did a demonstration by powering a 15 inch mtx sub with a 800 rms amp connected with 20 guage jumper leads. I was skeptical at first, but it pounded and shook the ceiling tiles loose. This is possible because the amplifiers output voltage is alot higher than the 12 volt input it receives, higher voltage=less amount of current needed

 
Rep Power: 0

8 guage speaker wire isn't overlydone. Honestly, i would hook up speaker wire as low a guage as the sub will accept. Mine is 8, so i use 8. And just becuase you have a dual 2 ohm voice coil sub, doesn't mean that each coil is exactly 2 ohms. Each setup is diff, the manufacturers just have to give a common quantity to make setups easier. My sub is dual 1.7 ohms. Close enough to 2 to not really matter. Its just an approximation set out by the manufacturers to make things easier. Could you imagine having to buy an amp to match a dual 1.7 ohm sub? It'd be crazy.

 
Rep Power: 256

Well if you had a dual 1.7ohm sub (dual 2 ohm), if it was only one sub, in order NOT to blow your amp up, the smart thing to do is wire the coils in series, bring it up to 4ohm which is safer for the amp. 8ga is def. overkill. You MUST upgrade your ground wire to 4ga. If power is 4, you must keep ground consistant, as it is the return path for the power. This can fix problems such as dimming headlights, etc.

I too went to Mobile Dynamics about 6 years ago, how long ago were you there?

 
Rep Power: 0

You could just wire the sub in parallel to one ohm, and run monoblock 1 ohm amp. 8 guage is less resistance than say 12 or 18. Also to high a guage can short out amps.