Abstract: The present invention enables music performers and sound engineers to perform collaboratively over a data network such as the internet. Each musician creates musical signals which are processed at two points: Signals are processed at a central server to produce a mix, which mix is subsequently distributed to all participants; Signals are additionally processed at each musician's location whereby each musician's track is removed from the mix and replaced with a local, low-latency version of said musician's track. In this way, musicians play to a real-time mix that satisfies the strict requirements for low delay. Using records of each musician's tracks kept at the server, musicians or sound engineers can post-process the tracks to create one or more master mixes in which delays are eliminated entirely and tracks are synchronized.

Abstract: A phase-controlled oscillator using a resonant tunneling diode (RTD), which is included in a self-oscillating biasing circuit. A biasing voltage controls the phase of the pulsating output relative to a pulsating input signal. If the output modulates a laser, the pulse position of the laser output can be varied in time. If the output modulates a microwave or other emitter have an electromagnetic frequency equal to that of the RTD biasing circuit, the electromagnetic phase of the emission is controlled, thereby allowing phase-array radars using multiple RTD biasing circuits. Also, multiple RTD biasing circuits can have self-oscillation frequencies which are rational fractions of a single master clock frequency driving all of them. The outputs then have different frequencies but are phase locked.