Over the years having attended dozens of huge gigs with shit sound, I've become more and more convinced that the real problem is cloth-eared sound engineers who, despite having tens of thousands of quids worth of state of the art technology at their fingertips, just can't do their job right.
On Wed at o2 the principle cause of all the extraneous noise and low frequency rumbling/droning was (as I believe is often the case) the bass drum. It was simply too loud and too bassy and it interacted with the bass guitar and created a really horrible wash of low frequency noise, leaving no space in the music itself and making it so much harder for the guitar and vocal to cut through.
The overall volume was simply too loud as well and just made the problems worse.
The worst concert sounds I've ever experienced were Rush at Wembley (1st night) on the S & A Tour three and a half years ago and ZZ Top - same venue, circa 1985 or 86. The sound was virtually the same at both these gigs
The o2 on Wed was a little bit better, but more crud than good.
In short - it's (imo) incompetence behind the sound desk more than the admitedly lousy natural acoustics of the venue. The equipment is easily capable of producing a much better sound
