Burst Generator

A burst generator is indispensable for testing the dynamic response of loudspeakers, and, in some cases, AF amplifiers. The fact that a number of cycles of a sinewave are applied to the loudspeaker under test, and not a con- tinuous signal, eliminates the adverse effects of reverberation, reflection and echoes which are otherwise caused by the test room, and are almost inevitably picked up by the test microphone. In addition, the burst provides a good indi- cation of the loudspeaker"s perform- ance in respect of voice coil transient response, resonance, and ringing. The test signal provided by an external sinewave generator is switched on and off at or around the zero crossing, de- pending on the setting of phase control Pi. The pause amplitude can be set by P2, while controls P3 and P4 are used for adjusting the duration of the pause and the burst respectively. It should be noted that the settings of these poten- tiometers interact, so that an oscillo- scope is required for corre...