A musical tone generating device includes: a nonvolatile storage device that stores musical tone waveform data; a volatile storage device; and a control means that, when a power supply is turned on, performs control to transfer musical tone waveform data to the volatile storage device from the nonvolatile storage device, in the case where an instruction to reproduce a musical tone is given, the control means to read musical tone waveform data from the volatile storage device, and in the case where an error in the read musical tone waveform data is detected, the control means to perform control to overwrite musical tone waveform data obtained by correcting the musical tone waveform data including the detected error to the volatile storage device or transfer normal musical tone waveform data corresponding to the musical tone waveform data including the detected error to the volatile storage device from the nonvolatile storage device.

Providing real-time interaction between a first player and a second player to collaborate for a musical performance over a network, includes maintaining a reference data item generated using a musical instrument performed by a user; receiving first user input data generated using a first musical instrument, the received first user input data associated with the first musical instrument and the musical performance; receiving second user input data generated using a second musical instrument, the received second user input data associated with the second musical instrument and the musical performance; detecting a missing data packet within the received second user input data when generating real-time collaboration data for the musical performance; replacing the missing data packet using the reference data item to correct the second user input data; and generating real-time collaboration data for the musical performance based on the corrected second user input data.

Plural portable devices, configured to produce special effect/s, responsive to a controller configured to provide instructions, on occasions separated by a time interval of t seconds, to transmitter/s, to transmit commands to the portable devices to produce a special effect at a time separated by S seconds from a first occasion, on which the devices receive from the controller commands to begin producing the special effect in S seconds. On a second occasion the devices receive from the controller commands to begin producing the special effect in (S-1) seconds, such that the plural devices produce the special effect synchronously and even devices which received only some of the commands transmitted, participate in production of special effects.