For customers used to listening to song libraries on their smartphones through tinny headphones, dropping into the TLX is a revelation of sorts: It sports the 17-speaker ELS Studio 3D, powered by a 710-watt amp, with acoustics designed by Elliot Scheiner, a sound engineer and music producer. He has won eight Grammys; he has produced the Foo Fighters, Sting, Bruce Hornsby, Paul Simon, B.B. King, Van Morrison, Donald Fagen, Queen, Eric Clapton, Jackson Browne, the Eagles and Joe Jackson. And others. Enough said.