hi all,

i have a jaycar 2 x 150 amp that i use to drive my jbl 15" sub for spl comps. the amp is fused at 60 amps and i have got a 40 amp fuse at the battery that has never blown. i was wondering if this means that it amp is not reaching its full potential? if so how do i get it to do so?

thanks
ross

okay, the fusing is there so it doesnt go pop 'if' there is a problem.

If, lets just say .. you had your wiring running through your fire wall without a grommet or some form of insulation and your power wire was rubbing and after a period of time, the positive then connects directly to the chassis and you have the ability to short your entire electrical system.. The idea behind the fusing is if that was to happen, the fuses would blow and your amp would not.

Fuses arent there to be broken, they are a functional peice of protection.. a condom for your cars electrical system, if you will.
So in short.. Yes, your amp should be reaching its full potential in its current wiring configuration.

Whats your sub rated it?

You must realise that the amplifiers and subs continuous output ratings are caluclated from a steady sine wave test tone. Its completely unlike music, and comparitevely high energy.

So, even when your systems cranking, it may never reach this maximum output continously, because music isnt constant. Bass beats draw more power than treble, for instance. If the fuse isn't blowing, theres no reason to change it.

The amp may not be reaching its full potential CONTINOUSLY but its not a big issue. The only way your going to get that high, constant, current draw is by playing contiuous test tones.

besides, your amp may make more power than the sub can handle, and so its never going to draw full current before the sub starts distorting/burning

hi all,

i only use this setup for spl comps so i am always just playing test tones and sine sweeps. i think the sub is rated at about 300 wrms and 1000 peak.

thanks
ross

Automotive fuses are the slow blowing type.. my experience has been you can get about 2x their rated blowing current thru them on a burp. Dont stress that it doesnt blow.. if it DOES blow there is a problem, not the other way around.