750 watts into an 8ohm 4x10 vs. 1100 watts into a 4ohm 4x10

[Washishimi]

Trying to figure out the differences (if any at all) between 750 watts into an 8ohm 4x10 VS. 1100 watts into a 4ohm 4x10. Any thoughts / ideas?
It's the same cab, just one is a 4 ohm version, and one is an 8ohm version.

[Mr. Foxen]

Fairly sure the cab will be showing signs of upset before you are even close to 750w, so it makes not much odds.

[billfitzmaurice]

Originally Posted by Washishimi

Trying to figure out the differences (if any at all) between 750 watts into an 8ohm 4x10 VS. 1100 watts into a 4ohm 4x10.

In all likelihood, none. With both driven to their full output capacity they'll have the same output. As to that capacity, it's determined by the excursion of the drivers, not their power rating, and will be the same for both cabs. That capability rarely is more than 1/2 the thermal power rating.

[KJung]

Originally Posted by Washishimi

Trying to figure out the differences (if any at all) between 750 watts into an 8ohm 4x10 VS. 1100 watts into a 4ohm 4x10. Any thoughts / ideas?
It's the same cab, just one is a 4 ohm version, and one is an 8ohm version.

Once you get to that high 8ohm wattage, you won't notice much difference. Going from 270 to 500 watts with a micro head... HUGE difference.

I'd go with the 8ohm in your situation.

[Bluesbob]

You'd have to know the efficiency rating of each cab in SPL's and plug it into a formula. I don't know the formula, maybe if you get the rating someone else could come up with it, or you could Google it. The answer will be in dB's.
The difference between the 8-ohm cab and 4-ohm cab is 3dB, everything else being equal - I think. This would be a perceptible difference, but not a large change in volume. And as Mr. Foxen says, you will probably not be able to use all those watts anyway with just one 4X10. If you believe the power ratings on most cabs - well, there's a bridge in Brooklyn that's for sale.

[KJung]

Originally Posted by Bluesbob

You'd have to know the efficiency rating of each cab in SPL's and plug it into a formula. I don't know the formula, maybe if you get the rating someone else could come up with it, or you could Google it. The answer will be in dB's.
The difference between the 8-ohm cab and 4-ohm cab is 3dB, everything else being equal - I think. This would be a perceptible difference, but not a large change in volume. And as Mr. Foxen says, you will probably not be able to use all those watts anyway with just one 4X10. If you believe the power ratings on most cabs - well, there's a bridge in Brooklyn that's for sale.

Just looking at db's does not really help with this issue. It is all about the relationship between having enough power so that you don't run out of headroom with an amp, and also the amount of power the cab can handle.

So, again, going from 270 to 500 watts will give you a meaningful 2db of volume increase, but much more importantly will, in many cases, result in the low end and entire feel of the rig to be more open and less compressed. And, as you point out, with a lower SPL cab that can handle the additional power, the difference can be a night and day experience.

Going from a very high 750 watts to a really high 1100 watts that most cabs (even large ones with multiple drivers) can't handle anyway.... probably no difference unless the cab is extremely low SPL.

[dpbass613]

I would go 8 ohm as well...why you ask? 750 watts is more than you need really for any gig, however if you get a 4 ohm cab and your head is only rated to to 4 ohms you can never add another cab, so go 8 ohms and if you find yourself playing larger stages you can add another 8 ohm 410 and get 1100 watts split to both cabs, 550 watts is enough to power those cabs sufficiently.

[The Fumble]

If he's runnig his LH1000 listed in his sig. (judging by the power ratings I assume this is correct) he can run 2 cabs at 4 ohms in dual parallel mode.

Cab choice is alot less limited with that particular amp.