Few rough demos.
Few rough demos recorded using Ardour (drums sequenced with Hydrogen, guitars made with Digitech GNX3000):
Oudated hardware e.g. Pentium4 1.5 GHz plus Sound Blaster Live at 10ms latency setting, after some serious tweaking can pull off up to 25 audio tracks with ease. Imagine, what Ardour can do running on better hardware :)