Del Casher, guitarist and inventor of the wah-wah pedal who played with Elvis Presley and Frank Zappa, dead at 88CelebrityNov 8 at 2:13 PM – Nov 8 at 3:15 PM3 outletsDaily MailDel Casher, guitarist and inventor of the wah-wah pedal who played with Elvis Presley and Frank Zappa, dead at 88 Nov 8 at 3:15 PMRolling StoneDel Casher, Guitarist Who Invented the Wah-Wah Pedal, Dead at 88 Nov 8 at 2:13 PMToronto SunDel Casher, wah-wah pedal inventor, reportedly dead at 88 Nov 8 at 2:16 PM