DISCLAIMER: this information might be out of date (and i sincerely hope it is
)
Oh man, let me tell you something. Twilight Force have taken the plague that is backing tracks, to it's logical extreme. EVERYTHING you hear live, comes through a laptop.
The drums have mutes on them to damp the natural sound, with triggers that are sent to a laptop to process them into crazy arena rock drums. The guitars are plugged straight into the laptop and processed with VST amplifier simulators, and all the guitar pedals and volume levels are automated throughout the songs onboard the computer too. Same for the vocals, all processed through the laptop, including turning on and off the backing vocal mics. And of course there's three billion metric fucktons of prerecorded orchestra and choir being played back. I have no idea what the human keyboard player is actually doing back there, apart from silly narrations.
They then give a multichannel output from the laptop to the Front of House enginner to mix together. Which is weird, i'd have thought they'd just simply give him a stereo mix and be done with it.
Anyway, when it works, it sounds weird and nothing like anything youve ever heard live before. When it doesn't work...like for example when they were supporting Gloryhammer on December 10th 2014 in a sweaty club in Hamburg...the laptop overheats & crashes, and there's this weird digital shitting-yourself noise over the PA like a record skipping for 3 seconds...then everything stops. Literally everything goes silent. No drums, no vocals, no guitars, no keys.
So yeah, that's how they do it.
As for playing with an orchestra, i mean it's entirely possible with enough budget. I know we've considered doing it one day for gloryhammer (everything we do is arranged for and theoretically playable by a real orchestra of sufficient talent).
