Edward M. Long is an audio engineer known for introducing the first near-field studio monitor

Studio monitor

Studio monitors, also called reference monitors, are loudspeakers specifically designed for audio production applications such as recording studios, filmmaking, television studios and radio studios where accurate audio reproduction is crucial....

s and the first time-aligned loudspeaker

Loudspeaker

A loudspeaker is an electroacoustic transducer that produces sound in response to an electrical audio signal input. Non-electrical loudspeakers were developed as accessories to telephone systems, but electronic amplification by vacuum tube made loudspeakers more generally useful...

 crossover

Audio crossover

Audio crossovers are a class of electronic filter used in audio applications. Most individual loudspeaker drivers are incapable of covering the entire audio spectrum from low frequencies to high frequencies with acceptable relative volume and lack of distortion so most hi-fi speaker systems use a...

. Long worked with Bag End and Ron Wickersham, and developed a method for extending low-frequency response in subwoofer

Subwoofer

A subwoofer is a woofer, or a complete loudspeaker, which is dedicated to the reproduction of low-pitched audio frequencies known as the "bass". The typical frequency range for a subwoofer is about 20–200 Hz for consumer products, below 100 Hz for professional live sound, and below...

s.

Long developed a passive crossover for loudspeakers which aligned the bandpasses in time. Patented in 1976 as "Time Alignment", the crossover design was influential in loudspeaker development from the late 1970s throughout the 1980s.