8ohm vs 4ohm cab?

[JTUK]

[quote name='xgsjx' timestamp='1416839551' post='2614089']
Why not go for two of the 8 ohm 2x12s you like?
[/quote]

I don't have the gig for it... I initially wanted 2x210 which is also an option
that I retain, but the 212 and 210 works great for me so that is my big stage rig
and the 4 ohm, 8 ohm thing is what I've settled for in terms of power spread.
Sound-wise, it is great so I am protecting the 210 when running high levels
of a potential 750/4 ohms output.
This is now also why I am keen to fine-tune my small lightweight rig so I can get the
tone and clarity of 212/210 into 2x112's which mean the 12" have to work or be able to work
harder tonally across the frequency range. Of course, I will have to compromise on the sheer
weight and authority of the big rig sound, but there you go.

[Phil Starr]

Changing the coil from 8ohms is going to change it's dimensions, less wire or thinner wire. This in turn (geddit) can mean a shorter voice coil and lower Xmax. It can also change the mass so higher resonance and all the other T/S parameters. Hence the sound may well be different. If the cone is the same then the upper part of the frequency range may be very similar, but of course you'd need to check that with the manufacturer. If the speakers are 16ohm drivers then they may have longer coils and better Xmax but lower efficiency and so on. The magnet may have been redesigned to match the new coil or it may not.

I'd say listen to both before buying, the possible extra volume from using 4ohms may be an illusion and won't be significant in any case, so choose the one that sounds best.

[Conan]

[quote name='Phil Starr' timestamp='1416842598' post='2614154']
...choose the one that sounds best.
[/quote]

I think our work here is done.

[xgsjx]

[quote name='JTUK' timestamp='1416840739' post='2614118']
I don't have the gig for it... I initially wanted 2x210 which is also an option
that I retain, but the 212 and 210 works great for me so that is my big stage rig
and the 4 ohm, 8 ohm thing is what I've settled for in terms of power spread.
Sound-wise, it is great so I am protecting the 210 when running high levels
of a potential 750/4 ohms output.
This is now also why I am keen to fine-tune my small lightweight rig so I can get the
tone and clarity of 212/210 into 2x112's which mean the 12" have to work or be able to work
harder tonally across the frequency range. Of course, I will have to compromise on the sheer
weight and authority of the big rig sound, but there you go.
[/quote]
If you find the 2x10 that you like the sound of, then there's no reason why two of them shouldn't be able to cover all your bases.
But then if the rig you have works for you, why change?

[Guest monsterthompson]

The 4/8 ohm wattage adjustment doesn't apply to valve heads. A 200w valve head will be 200w at 4 or 8ohms.

[JTUK]

[quote name='xgsjx' timestamp='1416856796' post='2614386']
If you find the 2x10 that you like the sound of, then there's no reason why two of them shouldn't be able to cover all your bases.
But then if the rig you have works for you, why change?
[/quote]

I think I can bottom out 2x210 with a 750w amp into 4 ohms.
The cabs take 700w combined and whilst I doubt I am hitting
anywhere to close to 750w... I feel I can hear the 2x210's
working very hard so I went with the DB212 as I loved it in the shop.
It was only when I traded it for a 4ohm version that I noticed the sound
change.
I now intend to run small gigs thru a TH500 in TKS S112's and I am
pretty sure that will give my the lightweight and clarity I want...
and my bigger gig will be the DB750 thru DB212 + DD210.
I can live with the DB212 sound on its own..easily, as long as my strings aren't
too gunky... as I don't like the sound to be too fat...as opposed to being full.