The diagrams on the amplifed sub I am planning on getting state that the main power lead should be drawn from a connector on the fuse box capable of drawing a consistent 10amps.

The information I have seen on here seems to suggest that most people run a power connector directly from the battery.

Is a connection from the battery a good alternative to running a line from the fuse box. If so why does the manufacturer suggest running the connector from the fuse box.

In an ideal world, the fuse box is fine if there is a free slot available that can cope with another 10 amps. However, I could not work out which one I could use, and I did not want to put another 10A through the already fully loaded system (heated seats, sunroof, etc). So, a new line from the battery (remember - fused as close to the battery as possible) was my only choice.

The tip of opening up a wing and feeding a cable through the sunroof drain grommet into the car is less scary than it first sounds If you don't have a sunroof, there will probably be no grommet and adding one is obviously advisable.

OK then a line from the battery it will be.

If my stereo has a system control output and an RCA output (which appear to be required in the instruction manual to complete an RCA connection) then I'll not need to draw a load off the fuse box.

However, if I have to go with a speaker level connection then I'll need to draw a 2 amp load from the fuse box.

Any thoughts on how I take a 2 amp feed off the fuse box would be appreciated.

If you are using a typical powered sub, it takes its juice from the new supply you are planning from the battery. The musical signal is fed over the two RCA(phono) connections (left and right). The head unit should have a switch cable that switches the sub on when the head unit is switched on (works like the low current supply to a relay). You should not need any extra power to the head unit or have I just not understood what you are trying to do?

I'm getting the same one you have Neil.
Looking at the manual it seems that if you use a speaker level connection (which I know you don't) it looks like there is a power cable which runs from the fuse box to the sub, presumably to let it know when the car is being used and its services may be required.
http://www.pioneer.co.uk/uk/products/25/130/TS-WX11A/media.html

In the RCA model it looks like that information / feed is given from the headunit's sytem remote output. I guess is more accurate as it only tells the sub to switch on when the stereo is on.

If you are using a typical powered sub, it takes its juice from the new supply you are planning from the battery. The musical signal is fed over the two RCA(phono) connections (left and right). The head unit should have a switch cable that switches the sub on when the head unit is switched on (works like the low current supply to a relay). You should not need any extra power to the head unit or have I just not understood what you are trying to do?

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