When does one need a headphone amp? I have some Shure 1840s, which are great, but I’ve read about headphone amps and want to be sure I am getting the most from the cans.
I have a Casio PX310 digital piano. When jacks are inserted into the (quarter-inch) line out sockets, the onboard speakers are not muted. They are muted when headphones (or a jack) are inserted...