Electronic sound signal generator achieving scratch sound effect using scratch readout from waveform memory

An electronic sound signal generator comprising:

• waveform storage means for storing sound waveform data;
• rate designation means for designating a reference readout rate to read out the waveform data from said waveform storage means in correspondence to a given pitch;
• scratch control means for generating scratch control data to control readout rate and readout direction, the scratch control data being indicative of a predetermined value when the readout rate and readout direction are not controlled;
• and
• readout control means for performing a control such that when the scratch control data is indicative of the predetermined value, the waveform data are read out from said waveform storage means in accordance with the reference readout rate, but when the scratch control data is indicative of an other value than the predetermined value, the waveform data are read out from said waveform storage means in a forward or reverse direction at a readout rate controlled in accordance with the other value.

An electronic sound signal generator comprising:

• waveform storage means for storing sound waveform data on plural cycles of a sound waveform;
• rate designation means for designating a readout rate to read out the waveform data from said waveform storage means in correspondence to a given pitch;
• scratch control means for, while the waveform sound data are read out, giving a reverse direction readout instruction;
• and
• readout control means for controlling readout from said waveform storage means of the sound waveform data in accordance with a combination of the readout rate designated by said rate designation means and the instruction given by said scratch control means,
• wherein said waveform storage means stores waveform data on attack and loop portions of the sound waveform, and reproduction of the sound waveform in a forward direction is performed by reading out the waveform data on the attack portion and then repetitively reading out the waveform data on the loop portion, and wherein when the reverse-direction readout instruction is given by said scratch control means while the waveform data on the loop portion are read out, said readout control means repetitively reads out only the waveform data on the loop portion in the reverse direction until the reverse-direction readout instruction is over.