While electronic music is currently all the rage, there was a time when it was a fairly underground phenomenon. If you wanted to check out ambient music, you had to seek it out at small record stores or go to raves. “When I first heard electronic music, it was way more poppy or way too heavy,” says Lotus bassist Jesse Miller, who started the electronic/jam band in 1999 with his brother Luke. “I never got into it, but then we got exposed to bands that were more ambient, especially the Orb and Underworld and these tracks that created a vibe and were really trancey and that became appealing to us, even though we weren’t producing electronic music.” The band gradually incorporated samplers and synths into the mix and started to attract a following by steadily playing the festival circuit. Its latest endeavor, Build, shows just how much the band has evolved. The opening track, “Break Build Burn,” for example, is a heady number that mixes and matches tape loops with funk riffs and jazzy fills. The band headlines Summerdance, a multi-band bill at Nelson Ledges. The event, which also features jam acts such as Future Rock, Orchard Lounge, Grimace Federation, Broccoli Samurai, Wanyama and Vibe & Direct, kicks off today and continues through Sunday. Tickets are $45-$90. (Niesel)