I have 2 Memphis 10s on a Coustic 800D amp. 18gauge on it now is this right?

 

I've always used 12ga. on subs and 16ga.-20ga. for speakers.

 

If I changed to 12 would there be a sound difference?

 

You can only pass so much power through a wire depending on the size. Kinda like comparing your garden water hose to the hose on a fire truck. If you needed water really fast, which would you rather have? You should be able to tell a difference if you are using quality speaker wire. I'm running 12 gauge Monster Cable even in my house on my surround sound for the Polks.

 

i suggested this read once last week some very good info here dispels alot of miths and misinformation about speaker wire go here
http://roger-russell.com/wire/wire.htm#wiretable
may i suggest taking the time to read the entire site very incitefull

 

18 gauge is not big enough for sub use with any kind of power at all. Wire that is too small causes too much resistance and effectively cuts the amp's power to the speaker. This is the main concern in this situation. The KIND of wire makes very little difference in the sound quality, but SIZE does matter in the resistance the amp is working against.

 

Also, running too small a size wire can cause a fire hazard, because too much voltage is trying to pass through too small of a conductor, it will get hot. Check your wires carefully to make sure your not having problems already, but it really depends on the power levels your using. I personally never use smaller than 16ga anywhere in an install, and thats only for speakers powered with less than 100w. For subs, I personally use 12ga minimum, usually I prefer 10ga for 300w per sub and under, 8ga for more than that. May be bit of an overkill, but it's never hurt me to go too big. Checkout knukonceptz.com for great prices on wire, comprable quality to Stinger and Monster, I've used it for a long time. Good luck dude.

 

So if my amp cuts off from time to time, it may be due to speaker wires?

 

i agree with the fact that if you run too small a wire there could be a detrimental effect on the sound quality from your speakers and that is because of increased resistance in the smaller gauge wire but to blitz 993 you need too get a few facts straight and please keep in mind that we are talking about speaker wires and not power wires because there is a big difference first of all it is not voltage that makes wire heat up its current flow or amperage and there is a big difference betwwen the two a 12ga wire according to nema and csa is good to pass 20 amp of current it wont get hot to the touch appreciably untill you start passing in the neighbourhood of 35 to 40 amps thru it continuosly i doubt very sincerely whether any car audio amp on the face of this earth puts out 20amps of speaker line current continously so this fire hazard thing does not hold much water again i stress we are talking speaker wire and not power cable power cable is a whole other kettle of fish another thing to consider isthe length of speaker wires most times speaker wires are not much longer than 15 18 feet so again no need for that much over kill so when i refer to a small wire i mean like 22 ga and smaller i am currently running an amp that makes 250 rms watts per channel and my subs are fed only with a 14 ga wire that is no longer than 10 feet and i would surmize no i know that going to a 12ga wire would not increase my sound quality one tiny bit but hey if you want to spend money on big honkin fancy pants wire its your money who am i to judge i am sure that 97f250 can advise us as to the typical average speaker line current amperage values

Robert R Konarski o/o of Konwire Solutions

 

It could be do to several things. First does your amp have a green light on it when it's on? Then do you have a red light that comes on when it cuts out? That will tell us more on what's going on... Mine cut out, and it was due too the wrong sub for the amp. The amp went into self protect, and shuts down.

 

This is totally OHM'S LAW material. One thing people need to remember is that half as much resistance requires double the capability of current flow. So, for example, if you change your sub from 4 ohms to 2, in order for your amp to produce the extra power you want it to, you need to make it possible with the proper wire size. And every number decrease of 3 on the AWG scale is double the conducting capability. So, 12 AWG will flow 4 times the current of 18 AWG.

The current draw can be calculated if you know the amp's output voltage and divide it by the impedance of the "load" the amp is driving, which includes the speaker wire.

 

I have them bridged to 2ohms (amp is 400 RMS & subs 250RMS 400peak)

 

No only one (red)

 

if you use the calculation I or amps =the square root of watts divided by ohms it will give you the the speaker line current so lets get really crazy here lets say you had an amp that put out 1600 watts RMS running a 4 ohm speaker the calculation would be as follows 1600divided by 4 =400 now the square root of 400 is 20 so that would mean you had 20amps of speaker line current but only if you are running that amp at wide open all the time i have never seen a 1600 watt rms sub amp( and before you get all up in my grill i know they are out there but they are how shall i say not a real common item if you get my drift and i am talking an RMS rating and not some inflated peak rating) and i don't really think that many of us here run stuff that meaty

 

I've read many articles like this before and one thing they never seem to address is amperage capability of the wire. I would guess because most of them are pertaining to home audio which does not need goddly amounts of power to try to fight through the sound loss from road noise and interior cancellation etc. But in the case of whether to run 18 guage wire on your 800watt amp to your subs? Is it worth risking the money you spent on the amp by not spending a couple of bucks on some 12 guage and a couple of minutes on rerunning it to your subs. Plus I think you already know the answer but you didn't have any 12g readily available when you installed your amp and now you just don't want to bother with it.