If I want to run 2 8ohm cabs through a 500watt head

[RickIronWitch]

500watts together?

Cheers

[Bill Fitzmaurice]

[quote name='RickIronWitch' post='1002509' date='Oct 27 2010, 09:30 AM']500watts together?

Cheers[/quote]Neither. Assuming your amp has a volume control you can use any power rated speaker with it. If the speakers distort turn it down.

[chris_b]

Your 500 watt head is probably rated at 500 watts at 4 ohm. So 2 8 ohm cabs = 4 ohm, which means that each cab will take 250 watts.

I would never run any gear flat out. Currently I'm probably using a lot less than half of my 500 watts into 800 watts of cabs.

[Lozz196]

As far as I understand it, the amp will split the 500 equally, so each cab will get 250. Providing its a 4 ohm amp that is.

But as the previous post states, running at max will more than likely distort if they aren`t both 250 or over, so turning down will stop this.

[warwickhunt]

As has been said by all of the above, you're quite safe... just use your ears!

As an aside (and it is alluded to above) has anyone ever run their 300/400/500w amp flat out... EVER? Even 30 years ago when 150w(ish) was the solid state norm (as opposed to the more recent 500w) for bassists, I rarely ran my amp anywhere near flat out. Just sayin'!

[Lozz196]

[quote name='warwickhunt' post='1002563' date='Oct 27 2010, 03:06 PM']As has been said by all of the above, you're quite safe... just use your ears!

As an aside (and it is alluded to above) has anyone ever run their 300/400/500w amp flat out... EVER? Even 30 years ago when 150w(ish) was the solid state norm (as opposed to the more recent 500w) for bassists, I rarely ran my amp anywhere near flat out. Just sayin'! [/quote]
Know what you mean, my 400watt @ 2ohms amp, into one 4ohm cab rarely goes above 2, unless its a very big or outdoor venue. It then goes up to 3!

[waynepunkdude]

My home cab is rated at 200W 8OHMs but I run 250W @ 8OHMs into it, I just treat it carefully.

[ThomBassmonkey]

I'd ignore wattage ratings altogether tbh. I couldn't turn up my old 480w head anywhere near fully before my 2 400w (so 800w total) cabs started distorting with my old rig and they'd only be recieving 240w each. Same now, not sure on the exact specs but my cab's rated wattage is higher than my amp's wattage and it distorts a long time before I'm at full volume.

So long as you use your ears and make sure the resistance is right, you'll be fine.

[JTUK]

I run 400w for nomally 4 ohms at the amp..2 8ohm cabs gives me max 400w capability and the cabs are rated 600w combined.
I normally like this 30 odd & markup on cab power.
Depending on your amp but it will probably start clipping before your cabs need to and you'll hear this. No one I know runs their amp flat out and it would prorbaly not sound so great if they did.

Also, cab impedence is variable so you probably aren't running 4 ohms anyway so something over that.
At the end of the day, it doesn't matter what you have as ears can't equate to watts..if it sounds distorted you should be turning down.

Your idea to run 2 8 ohm cabs that total ( bewteen them) over the amps rating is a good place to start.