But not only did Springsteen use the Panasonic for mixdown; he also, in the mix process, put all the recordings through a Gibson Echoplex, which put a layer of early Sun Records–style slap echo on, well, everything: vocals, guitars, harmonica, percussion, glockenspiel. As decisions go, to mix every recorded track on a multitrack recording through a single effect is certainly not the kind of choice professional engineers tended to make when they were creating recordings for commercial release.