Variations in the speed of playback of a recorded signal resulting in pitch variations and distortions. Wow has to do with small speed variations resulting in a wobbling sound. Flutter deals primarily with quicker speed fluctuations. Wow is a slower form of flutter. The two cause audible distortions in the reproduced signal. hink of driving down the highway at a constant speed of 60 miles per hour versus slowing down to 55 then speeding up to 65 then slowing down again and so on to average 60. The engine emits a steady, constant sound at the constant speed. However, when the car speeds up and slows down constantly, the engine noise lessens then revs up to a high level then lessens, etc. This is similar in concept to the effect of wow and flutter. ow and flutter is given as a percentage and the lower the percentage the better. Wow and flutter is primarily an issue with cassette tapes and records.