What size wire do I need for 500 watt speakers??? (250 watt RMS)?

The correct speaker wire gauge depends on speaker impedance and lengh of the cable to run.

Gauge numbers used for speaker wires are 10, 12, 14, 16, 18, 20 and 22

Larger gauge numbers indicate "lighter" wires. HTiBs and speaker packages usually come with 20 or 22 gauge speaker wires.

Smaller gauge numbers indicate "heavier" wires. Usually 16 gauge speaker cable is enough for most Home Theater applications.

To use lighter speaker wire (larger gauge) than the recommended will waste amplifier power because the lighter wires offer more resistance so speakers will not sound as they should. To use heavier speaker wire (smaller gauge) than the recommended will do nothing to improve sound so you will just waste some money.

To know wich wire gauge is recommended to your specific set-up then visit this link and see the table:

http://www.roger-russell.com/wire/wire.htm#wiretab...

Same recommendations are posted on JBL professional FAQ page on this link (But is a graphic that is more diffcult to read):

500 Watt Speakers

It really depends on how long you plan to run the wires. I assume you meant 16 Gauge rather than 6. If you're running the wires longer than 50 feet, I wouldn't use less than 14 gauge. It's hard to go wrong with 12 gauge. The reason for this, though is for signal quality and resisting interference. You're not going to start any fires with speakers. Otherwise you'd likely need an electrician to install it.

Hi. The thickness of the speaker cables depends on the distance between your speaker input terminals and the amplifier output terminals.To get the best possible signal the length of the wires should be as short as possible with the resistance of the wires as low as possible.The wires should be well insulated and flexible enough to bend if needed.They should be airtight to prevent oxidization .As a rule of thumb longer runs need thicker wires to prevent signal degradation.But i would use thick wire (12Gauge) even for short runs to be on the safe side.You can buy the wire to the length you want and you don't have to spend a fortune on very exotic cables just ones that do the job correctly. If you know how much you need you can get the guys who sell it to put good quality connectors on the ends of your wires unless you have some of your own.You want them to have a secure fit.This ensures a good transfer of the signal from the amp to the speakers .I have found through my own experience that silver coated copper wire gives you the best sound from your speakers.Most of the home theater enthusiasts on answers will tell you that it is impossible to hear any difference by using different loudspeaker cables.The cables i use are Van Den Hul from The Netherlands. They were not very expensive but they are well made with very good gold plated connectors.. Hope that helps a bit and good luck for what you decide on.

20 gauge is way too thin (the higher the gauge number, the thinner the wire). I'd say you'd be pretty good with 14 gauge. However, if you're running this through a wall, you're supposed to get special cable designed for being inside walls (it's more fire resistant and less likely to start a fire) - it should be labeled on the spool.

Yes

its not the rating of the speaker,rather the amp rating that ill be supplying power to the speaker.

don't run lamp cord get good quality interconnects, that includes speaker CABLE!