Twizza, thanks for the details (and I’m glad the combo got resolved). Here’s some late-night ramblings from a bassman…
Although I don’t have Avatar cabs, I hear very good things from The Bottom Line forum about Dave. You will, most likely, get more useful ops from him than me, f’r’instance. The 1960, OTOH, is an off-the-shelf Marshall cab and I bet you get little pre-purchase support compared with Avatar.
OK, cab construction. Absolutely nothing wrong with birch-faced plywood. Good compromise of lightish weight, rigidity and the right sound. Medium Density Fibreboard (MDF) weighs a ton and comprises floor-scrapings held together by resin-yack. You can go the whole hog and look into Thiele-Small parameters (I can’t even remember the correct spelling) but good cab makers have already done this.
Secondly, the stereo thing. The Randall has a stereo chorus. I’m not that big-dealed on the usefulness of stereo chorus (maybe for Def Leppard?) but remember that a stereo speaker cab is only as good as the separation. If you have a 4×12″, even wired up separately for stereo, it won’t sound much different from mono. Imagine your hifi with the speakers stuck together – not very stereo.
The 4ohms allows the max possible output. I’m surprised at how conservative the claimed increase is (120W vs 100W) so I’d guess ‘bad’ distortion is not an issue. I’m not over-keen on your previous advice. The 8ohm would only sound better if a lower impedance were stretching things and you were diming it. Doubt very much if the slight increase in W for 4ohm makes things pear-shaped.
In all humility, though, I think you’ll get more sense bouncing this off Dave at Avatar. FWIW, I think those cabs look cool and are reasonably priced. Choice of drivers, too – well worth sending another e-nquiry.