What I posted before was for the SQ-1, not the ESQ-1...this is for ESQ-1
1. Press and hold the (RECORD) button
2. Press Soft button (1) (upper left hand corner of screen), then release both buttons.
3. Display = ERASE ALL MEMORY AND RE-INITIALIZE
4. Select YES. The display returns to the sign-on message. All RAM is erased and all internal programs are reset
5. Press and hold (RECORD) button
6. Press the (FILTER) button, then release both buttons (verify that all filter values are between 140 and 160 inclusive, if they are not within these values you should probably have your unit serviced at an authorized service center).
Note: When re-initializing with O.S. version 2.2 and lower, all internal programs will reset to BRASS 1. Higher versions will load the forty factory sounds.
I listened to Hatfield and the North at Rainbow. They were very wonderful and they made my heart a prisoner.