napalmdemos

I got a new 400 watt amp today and its a little bigger than the old amp (200 watts) so I need a bigger lead wire should I go with a 6 or 8 gauge?
Also how did every one run this wire (pics would be awesome) because the place I ran the old 10 gauge is to small for a 6 or 8 gauge wire (without drilling) to run.
Is a capacitor needed for this small of a amp? Ive never used one before and I dont want to waste my money if I dont need it.

hydric

qouting someone off this board:
8 awg is good for 500 watts
4 awg = 800
2 awg = 1500
single ott (1-0 awg) 2000+ but no third gen needs that.

- cheers for the copy n paste, i'm lazy.

a capacitor? No, not unless your amp was 500 watts n above should you get one or if your lights flicker when the bass hits, but yours shouldn't. I would get a fuse holder (you probably already have one that came with your old wiring kit)

TomP

Well, hold on a second. What's the brand name and model number of the amp? What size fuse is on the amp?

Just asking because your 10 gauge wire might wind up to be more than adequate depending on that the amp is, or isn't.

napalmdemos

400watt Jensen dont know the model # off hand.
But when the amp is on the power light flashes with the beat of the music and if ya get it to loud it shuts off to protect.
Another question if the lead wire is switched to (lets say) 8 gauge should the ground also be a 8 gauge?

The gain is not maxxed out (only about 1/3 of the way up) so that cant be it, well you wouldnt think it would be.

And I thought it was kick a$$ I got a new amp, turns out to be a pita.

TomP

Yeah, ground wire should always be the same size as the power wire. So if your power is 8 gauge, ground should also be 8 gauge. Is that Jensen the XA4100 or 4200? I think those have 25 amp fuses on them...? Go by the fuse, that's the safest bet. If you're doing a long run to the trunk, 8 gauge would be fine for "total of fuses" being 25 to 65. The longer the run, the bigger the wire you need... especially if you run the wire under carpet at all. Where did you lead the power wire thru the firewall? You said you can't get a larger wire through... will a drill not fit?

napalmdemos

It has a 25 amp fuse in it.
A400hlx is the model.
I ran the 10 gauge wire through the fender and into the kick panel then ran it under the trim all the way back to the amp.
The 10 gauge barely fit so I dont think the 8 gauge would work and I really dont want to drill through the firewall.

Jim85IROC

iTrader: (2)

I'd like to know who so that I can make sure he never wires a car I go near.

Power output of the amp means nothing. Current consumption is what matters, and it breaks down like this:

Length of run (in feet)
Current 0-4 4-7 7-10 10-13 13-16 16-19 19-22 22-28

0-20A 14 12 12 10 10 8 8 8
20-35A 12 10 8 8 6 6 6 4
35-50A 10 8 8 6 6 4 4 4
50-65A 8 8 6 4 4 4 4 2
65-85A 6 6 4 4 2 2 2 0
85-105A 6 6 4 2 2 2 2 0
105-125A 4 4 4 2 2 0 0 0
125-150A 2 2 2 2 0 0 0 00

TomP

Jim, are those numbers for being 100% covered up by carpet?

Napalm, your wire goes outside of the car? Wild! You might not have to drill a hole in the firewall. (I've drilled a few by now! ) Look under the hood, by the brake booster. You might have a round plug in the firewall, about an inch in diameter. If you do, you just need to remove the hush panel (black panel above driver's feet), and knock the plug in towards the engine compartment with a hammer and punch.

If not, there's enough things in there to give you a good guide as to where you can drill a hole. Remember to use a rubber grommet around the hole so the sharp sheetmetal doesn't cut into the power cord and start a fire. Radio Shack sells (or, used to sell) a bag of different sized grommets for $2. And always drill from teh "inside" of the car towards the engine compartment.

That amp has two 25 amp fuses, right? Specs I found were 50 watts RMS x 4 channels at 4 ohms, 150 watts RMS x 2 channels bridged at 4 ohms.

napalmdemos

While we are on the subject what size remote wire should I use?
I am still currently using the one from the old 10 gauge wire kit.

Jim85IROC

iTrader: (2)

Tom, those are the IASCA mandated sizes. If you look at the actual current capacity of the wire, you'll see that IASCA's regulations are a bit conservative, but they follow the "better safe than sorry" philosophy, and those numbers have pretty much been adapted as the industry standard. If you compete and don't meet that chart, you get docked a LOT of points.

If memory serves me right, IASCA came up with those sizes based on a maximum of a .5 volt voltage drop at the amp, so even though smaller wire may be "safe", you're going to see voltage drops of 1 or more volts in many cases, which can have a large effect on how much power the amp can produce.

napalmdemos

Got it fixed today decided to drop down to a 4gauge wire and use a 80 amp fuse box under the hood then ran it to the back seats then dropped to a 8 gauge then to the amp. Works awesome. Thanks everyone for thier help.

brobert

10 ga wire? damn my remote turn on wire is 10 ga. Id never use that on an amp(for power). When i first put in my amp i used 8 ga wire, the amp was a 400 watt pioneer, Ran to two 6x9's and a 10" sub wired tri way. When the bass hit my lites dimmed. I knew i needed thicker wire but being a dumbass i didnt get it, Now i have the pioneer amp ran to the 10" sub bridged. And another 400 watt amp ran to the 6x9's. As soon as the slightest bass comes in you can tell i need thicker wire. So off to home depot i go to get some 4 ga, hell maybe even 2. And then down the line maybe ill pick up a cap,. Not sure if i want one yet, i only have 1 sub.. I think alot of people are misinformed on what size wire they should use for an amp, I remember one day this guy was outside my work with his hood open, when i went over to the car he had this thin wire, i think maybe 10 ga ran to a 1000 watt amp, it got so hot it melted his coolant tank and part of his battery term!

napalmdemos

When your running a 2 channel 200 watt amp that might be pushing 50 rms per channel a 10 gauge power wire will work just fine.

Jim85IROC

iTrader: (2)

The great thing about being an electrical engineer and a seasoned veteran in the car audio world is that I'm able to know the difference between overkill and plain stupidity, and in the process, I'm able to save a lot of money.

10 gauge wire for a remote lead that has a 0.5amp maximum current draw is plain stupid.

brobert

Ripping the wire out when it was in the car when i got it ( ran under the rug to the back) is just stupid also.

Jim85IROC

iTrader: (2)

Then why are you bragging about it? You apparently had nothing to do with it and used it simply as a matter of convenience.

brobert

im not bragging, bragging would be like me saying, "the great thing about being an electrical eng" etc. Like YOU did, i was just saying i wouldnt use 10 ga wire for anything else, why dont you stop acting like an *** and get a life. I wasnt replying to any post you made anyway.

Jim85IROC

iTrader: (2)

Whatever. I'm just pointing out that your comment about not using 10 gauge wire isn't too accurate. 10 gauge wire is perfectly adequate for certain size amps, and it has nothing to do with their rated power output.

As for mentioning that I'm an EE, you can call it bragging if you like. I'm certainly not ashamed of my degree, in fact I'm quite proud of it, but the reason that I mention it on occasion is that sometimes it helps me avoid stupid arguements with some self-proclaimed "expert" who doesn't know his *** from a hole in the ground. More times than I care to remember I got involved in silly arguements with people that thought they knew it all, yet didn't even know enough to formulate a reasonable discussion. By mentioning my degree, somehow it seems that a lot of these idiots keep their mouths shut and more intelligent conversation develops.

Daishi

Just for looks I ran 4 Gage to a 350 WATT Kenwood, powering 2 12" clarions. I got WAYYYYYY to big of wiring, but not like its hurting anything. And for $90 for the Entire car kit, You can't go wrong

P.S. You Dont need a Cap unless you are running crazy power Amps. I know someone running an 800 watt amp with no farad cap, and Its fine. Kinda Depends on ur Altenator too

Another Side Note, You can fit a 4 Gage wire thru the hole for ur Hood release button, just peel back the rubber fitting and There is room for the two of them. Just a thought

brobert

I see you point on the degree thing, i took your post as harsh because you said about the wire being stupid, i took you to be one of those know it alls on here that i have ran into also. Even one of the mods on here was wrong and when i pointed it out he changed the subject. The reason i would not use 10 wire on an amp is i guess because i seen it over heat and what could happen. Yeah if you have the right fuse wire size combo itll never over heat but still. Also, i have worked in the electrical field in the past, i have rewired my home completely, down to every wire nut and light switch and socket, i think youd agree that is a much harder task than wiring an amp in a car. But some people on here dont car who you are or what you know. It seems they are just here to argue. And that is they reason im really getting edgy about these posts.

Jim85IROC

iTrader: (2)

I understand your concern with using 10 AWG wire, and if you have an amp that will grossly exceed the current capacity of the 10 AWG wire, it's a legitimate concern, but you need some pretty massive current to heat up a piece of 10 AWG wire. A "typical" 400 watt amp isn't going to pull nearly enough current to cause that to happen.

But in any case, using bigger wire than necessary isn't going to cause any problems, so it's better to be safe than sorry.

TomP

My amp turn on lead is 18 gauge, if that helps the discussion any.