speaker wire and inline fuse q's

[gijoe 10+ year member]

I have three questions that I figured I'd try to clear up in one thread. Hopefully you all can help out.

Question 1: Is there a big audible difference in the gauge of speaker wire used? I'm running two IDQ 10's off of a xenon 600.1 (birth certificate says 851watts rms). I should be running at least 12 gauge wires from amp to subs correct? I'm currently only running 16 gauge. Since I've only got about 2 1/2 feet of wire, will there be an audible difference by getting the recommended gauge wire? I know that with longer lengths the gauge becomes more important, but at such small lenghts will the upgrade even be audible?

Question 2: Inline fuses protect the power wire and the fuse(s) in the amp actually protect the amp correct? Well my amp recommends a 60 amp fuse and I'm assuming this means inline since none of the fuses in the amp are accesible without dissassembling the amp. I have 4 gauge power and grounds, which can handle a lot more than 60amps worth of current without being damaged, but I only have a 40 amp fuse in right now. Since this 40 amp fuse hasn't blown yet, does that mean that my amp hasn't ever tried to pull more than 40amps of current? Would going to a 60 amp fuse in anyway effect the amps performance?

Question 3: My subs are recommended at 250watts rms, and apparently my amp will do 851watts rms. I have the gains set way low, because there was just too much bass for my tastes. My goal is a decent sq setup, and I'm wondering if I'm losing sq by having my gains too low. Should I use a meter and set my gains according to the voltage and then just use my hu (880prs) to tune my subs to a nice sq volume, or will I have the same sq by keeping my gains low? I don't want to give my poor 10's more power than they can handle daily.

Thanks everyone for reading and any input on any of these questions will be very helpfull. I want to learn all of this stuff correctly, I'd rather buy bigger equipment than I need and not max it out, than to try to squeeze everthing out of my equipment and end up damaging it.

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[gijoe 10+ year member]

back up

 

[bigbirney420 10+ year member]

With your wattage 16 gauge will do fine, especially with that short of a run. The 40 amp fuse should be enough with your setup, mainly because the amp is way down. Typically if it hasnt blown, it means it not drawing too much current. You can step up to a 60, but if the 40 is working thats fine. Lastly you dont lose any SQ by having gains set low. If anything you may gain a little due to no clipping issues and everything not getting all overworked. I hope this clears some of that up.

 

[n2audio 5,000+ posts]

I have three questions that I figured I'd try to clear up in one thread. Hopefully you all can help out.
Question 1: will there be an audible difference by getting the recommended gauge wire?

no, but at 4 ohms - peaks are going to draw about 13A

at 2 ohms - 19A

at 1 - 26A

All are too much for 16 ga. The difference between inaudible and "right" isn't often a lot. Your wire IS seeing some heat, and IS dropping unnecessary voltage which isn't doing anyone any good. Audibility isn't the issue.

Spend the couple bucks and put some 12 in there.

Question 2: I only have a 40 amp fuse in right now. Since this 40 amp fuse hasn't blown yet, does that mean that my amp hasn't ever tried to pull more than 40amps of current?

Not necessarily, just that it hasn't drawn 40 or more for long enough to heat the fuse up and melt the element. A 40A fuse should have no problem drawing 50-60A for a few seconds.

Would going to a 60 amp fuse in anyway effect the amps performance?

No. It would reduce voltage drop through the fuse by -- I don't know - 1/100 of an ohm? Maybe in the 1/1000's. I kinda doubt that'll change anything.

Question 3: I'm wondering if I'm losing sq by having my gains too low. Should I use a meter and set my gains according to the voltage and then just use my hu (880prs) to tune my subs to a nice sq volume, or will I have the same sq by keeping my gains low? I don't want to give my poor 10's more power than they can handle daily.

I'd set the gain a little low but do it with the sub volume in the middle of its range. That way you know at neutral sub volume they'll always be safe and when you want to show it off a little it would still take a big screw up to put them under stress. Plus, having sub control from the HU is always a plus.

Thanks everyone for reading and any input on any of these questions will be very helpfull. I want to learn all of this stuff correctly, I'd rather buy bigger equipment than I need and not max it out, than to try to squeeze everthing out of my equipment and end up damaging it.

That's a great way to go about it IMO.

 

[gijoe 10+ year member]

Thanks, I think I'll head out and get some speaker wire and a fuse if I can find one. I didn't mention before but my subs are wired together using the same 16 gauge wire that I'm running to the amp, I imagine it'll be in my best interest to rewire my subs with 12 gauge while I'm at it. Thanks for the input, anymore comments are welcome.

 

[XanderMoser 10+ year member]

no, but at 4 ohms - peaks are going to draw about 13Aat 2 ohms - 19A

at 1 - 26A

All are too much for 16 ga. The difference between inaudible and "right" isn't often the same. Your wire IS seeing some heat, and IS dropping unnecessary voltage which isn't doing anyone any good. Audibility isn't the issue.

Spend the couple bucks and put some 12 in there.

Just wondering, is this how you got the numbers...?

Current draw at 4 ohms at RMS for both subs:

----------------------------------

250watts * 2 = 500 watts

500 watts x 4 ohms = 2000 V^2 = 44.7 V

44.7 V / 4 ohms = 11.1 amps

Current draw at 2 ohms at RMS for both subs:

----------------------------------

250watts * 2 = 500 watts

500 watts x 2 ohms = 1000 V^2 = 31.6 V

31.6 V / 2 ohms = 15.8 amps

Current draw at 1 ohm at RMS for both subs:

----------------------------------

250watts * 2 = 500 watts

500 watts x 1 ohm = 500 V^2 = 22.4 V

22.4 V / 1 ohm = 22.4 amps

From my experience, speaker wire gauge should be chosen depending on the impedance of the speaker and the length of the run. This is because you do not want the resistance of the wire to be great than 10% (prefereably 5%) of the impedance of the driver. So the longer the run, the thicker the wire for the same impedance. So for short distances, you don't need thick wire.

 

[n2audio 5,000+ posts]

I was using 750w which I figured was conservative given the birthsheet.

Even at 500...What's a couple bucks to do it the right way?