Since dropping the anomalous techno gem Neon Rocka as Subhead in 2000, British producer Jason Leach has become obsessed with “ruckno,” a ramshackle mash-up of rap, rock, electro, and techno. This overlong double disc features 37 tracks by Circa, Royal Blood and Carrion Crow, groups whose common link is Leach. Circa come off as a parody of machismo-poisoned rap, Prince, Gary Glitter and grunge rock. If Cockneys had frat parties, Circa would be the house band. Royal Blood and Carrion Crow fare better, forging unclich?d electro and techno that’s weirdly torqued, visceral, and distorted. Leach has talent, but he needs to focus on his strengths.