Who plays the music and who deals with the baby? New-ish parents Billy Gomberg and Anne Guthrie had to deal with that question as they made Heavy Objects, and that circumstance offers one explanation for the tape’s restraint. While a French horn, bass guitar, digital recorder and synthesizer were all hefted during the recording session, it certainly doesn’t sound like anything heavy was played, let alone dropped. Instead distant environmental recordings negotiate for space with other recordings of hushed in-home activity — the filling of a glass or papers being moved around a table. The musical instruments are heard one note at a time, almost reluctantly, as though whoever was playing them was trying hard not to wake the kid. The result is music well suited to quiet headset listening. Pop the tape in your Walkman or the files in your phone and play them almost subliminally while you shop or stroll, and savor the moment when you can’t tell if the radio or car horn you’re hearing comes from the music or the space you’re traversing. But if you’re easily frightened, you might want to audition side two once in the safety of your home first; I don’t want to spoil the surprise, but there is one sound on it that you’d much rather hear coming from a recording than the street.