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pimp86LX
04-02-2003, 12:07 AM
hey there

k, i rewired my speaker box and the resistance measured went from 1.9ohms to .49ohms. (measuring the actual resistance of the wires, not the coil)

How do i equate that into power handling?

P=I*V? or is that for DC currents only?


help!

shepherd79
04-02-2003, 04:30 AM
so you went from 2ohm to 1ohm.
what subs do you have? make and model?
now that you have lower impendence subs, you need to get new amplifier that can handle lower impendence.
By lowering impendence you allow subs to handle more power, but at the same time you lower (it may not be much) you SQ level
what kind amp do you have? make and model

n88accordLX-i
04-02-2003, 10:02 AM
Wrong, lower impedance doesnt give a sub more power handling, subs come in different ohms for wiring flexability, nothing more, but if you have an amp that does 500watts at 2ohm and 1000watts at 1ohm, your obviously gonna get more power out of your amp running a lower ohm sub setup.

dXsquared
04-02-2003, 10:07 AM
less resistance = lots of power... you should make a cooling box thing for the amp, with an intake and an exhaust fan... it will get hot.. you must also have an amp with an unregulated powersupply that will run a .5 ohm load. there are a few out there, but they are very high power... let us know what your running.. i wanna hear about this

Travis

pimp86LX
04-02-2003, 10:50 AM
speakers are 4ohms, amp is 300w @ 2ohm stable.

its much clearer but not much louder, i figure the lower resistance wires in the box just puts less of a drain on the system.

POS carb
04-02-2003, 10:55 AM
no!!! don't do that. Lower resistance = more current = more strain

POS carb
04-02-2003, 11:00 AM
here's how it goes
power=voltage/resist.
if resistance is less then power increases.
technically your amp does produce more power at lower resistance however many amps aren't stable enough to handle a 0.5 ohm load and would overheat (if the protection circuitry lets you).

How many coils does each sub have, how many ohms each coil, how many subsm and how many channels is your amp.

pimp86LX
04-02-2003, 11:04 AM
ok you guys misunderstood. even though i stated in the first post

i didn't touch the coils or the subs. the wires going from the subs to the terminal in the side of the box were shitty and old. I replaced them. i measured the resistance of a straight piece of wire, not the coil. the amp is still running at 4ohm.

POS carb
04-02-2003, 11:37 AM
OH my bad. well there's not really an exact way to arrive at that but you could start by adding the resistances, cross multiplying and dividing. 300/4 = x1/5.9 and 300/4 = x2/4.5

x1 is your previous power, x2 is your new power. x2-x1 = your power gains

pimp86LX
04-02-2003, 11:45 AM
yah, its not really an issue anymore, its noticable to my ear, so im happy :D

pimp86LX
04-02-2003, 11:56 AM
with that i want to say how its all in the setup!!! i have a $700can setup, that can hit 145db :D:D wich is way more than enough for everyday listening. All in the setup!

shepherd79
04-02-2003, 02:25 PM
ohhhhh, i see now.
if you change the wire between amp and sub, i don't think you will get much increase.

pimp86LX
04-02-2003, 02:40 PM
heh heh if you saw what used to be in there you would disagree :P it was so shotty, spliced 2 or 3 times, and it wasn't much thicker than headphone wires. I was thinking my no name subs were really really shitty, but something told me to check it out. and wow its much clearer sounding :D:D

ohya, got another question...

my amp is 150x2 @ 4ohms, wiring my subs in paralell will allow for 2ohms ? my amp can be bridged and is stable for 2ohms. I just need reassurance before i try

POS carb
04-02-2003, 05:08 PM
it needs to be stable to 1 ohm / channel in stereo for that to work

shepherd79
04-02-2003, 06:07 PM
Originally posted by POS carb
it needs to be stable to 1 ohm / channel in stereo for that to work

what are you talking about?
he has subs that are 4ohm. he can wire them into 2ohm and run on his amp at 2ohm stable.

pimp86LX
04-02-2003, 06:10 PM
ah the utter chaos!

who is right! :-P

POS carb
04-02-2003, 06:22 PM
yea but a bridged amp sees 1/2 the resistance so a 1 ohm stereo amp is only stable to 2 ohms in bridged mode

POS carb
04-02-2003, 06:27 PM
look if your amp is 150x 2 @ 4 ohms then it's probably 300x2 @ 2 ohms and 600x1 into 4 ohms. if you notice the 4 ohm mono power is the sum of the 2 ohm stereo channels.
SOOOO... run 150 per sub per channel if it's 2 ohm stable in stereo or get some DVC subs

trust me I went on a mission to pics some subs that will match my amp setup and I'm going to be getting some dual 4 ohm subs with 2 bridged channels per coil. I've studied this crap a long time

POS carb
04-02-2003, 06:33 PM
further clarification: if the 2 4-ohm subs are wired parallel you get a single 2 ohm load. The bridged amp will then "see" a 1 ohm load" and whatever happens after that is up to you to find out.

pimp86LX
04-02-2003, 06:39 PM
if its 2 then why would the amp "see" 1?

shepherd79
04-03-2003, 04:27 AM
Originally posted by pimp86LX
i rewired my speaker box and the resistance measured went from 1.9ohms to .49ohms. (measuring the actual resistance of the wires, not the coil)


again, i would like to point out that he measured the resistance of the WIRE that goes from the sub to the end of the box. he didn't measure the coil.
if he would measure resistnace of the coil it would be about 3.5ohm or somewhere between 3.2 and 4ohm.
there is no way you can wire 2 4ohm subs to make it .5 ohm. even if you wire them in 2ohm load you won't get .5ohm on the coil.
he can run his system just fine.

POS carb
04-03-2003, 06:49 AM
yea but now were back to what we started on which is him trying to wire 2 4-ohm subs to a single channel which can only be done with an amp that is 2-ohm stable in mono or 1 ohm stable in stereo.

shepherd79
04-04-2003, 04:17 AM
he said that his amp is stable at 300W@2ohm load.

POS carb
04-04-2003, 11:16 AM
yea but bridged channels see half so it would see a 1 ohm load

AccordEpicenter
04-06-2003, 08:19 AM
think of it this way, when you have a 2 channel amp, each side has its own set of outputs, so if you were going to wire it up to run 2 ohm on each channel for 200w per side, then when bridged you can only go down to 4ohm because then youre using both sides of the amp to get the 400w