Netlabels in general tend to release electronic music. The netlabel named Test Tube releases its share of electronica for free download, but it also ventures into pop and various experimental realms more often than do many of its online peers. Still, the label’s roots are in atmospheric electronic music, and those roots often make themselves shown, even where they’re not expected. Take the recent instrumental-pop set The Door by Multi-Panel (aka Dutch musician Ludo Maas). While most of the songs are nostalgic, lilting melodic lines above gentle percussion, the title track is a beatific, clouds-opening expanse of glimmer; the closest thing in it to a percussion element is a set of chatty little vocal samples that cycle through, all chopped and blended (MP3). It’s delightful. More info at monocromatica.com/netlabel.