Roland E-4 Owner's Manual page 23

Layering audio recordings (overdub)
1. Press the [â/ó] (play/record) button when playback or recording is stopped.
Playback begins.
The [â/ó] (play/record) button lights up green.
2. Press the [â/ó] (play/record) button again.
Recording starts when you press the button.
During recording, the [â/ó] (play/record) button lights up red and "rEC" is displayed.
Using the Looper
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