Apex was an experimental radio broadcasting system introduced in the United States in 1934 that used high frequencies between roughly 25 and 42 MHz and wideband AM modulation (as opposed to traditional AM broadcasting's narrowband modulation) to achieve high fidelity sound with less static and distortion than medium wave AM stations in the so-called standard broadcast band (then, 545-1505 kHz) experience. They were called "apex", "skyscraper" or "pinnacle" stations because of the height of the broadcast antennas used.