The Pro Rock'r is a two-point tremolo which pivots on a pair of knife edges resting against two posts mounted in the guitar body. Strings are loaded from the bottom of the tremolo with the ball ends attached and sit in six independent saddles. Each string is securely held in the saddle using individual string pressure pads. It was paired with the behind-the-nut Top Lok or Top Lok II string locks to create a double locking tremolo system, the first such system employed by Ibanez.
The overall height of the Pro Rock'r could be adjusted by screwing the posts in or out. It was not recessed in the body like the more familiar designs which have followed but instead sat on or just above the top similar to a traditional Fender tremolo. The height of each saddle could be adjusted independently to set the string action. Each saddle can move forward and back using screws running through the back of the tremolo body to adjust intonation. A holding screw allows each saddle to be locked down once intonation is set. A fine tuning wheel on each saddle allows the strings to be tuned without unlocking the string lock at the headstock.
The Pro Rock'r used a newly designed snap-in arm mechanism. Arm torque is maintained by a pair of teflon bushings which are fitted on the arm. These bushings wear over time and can be replaced to regain the desired torque. This arm mechanism outlived the Pro Rock'r and was retained on future Ibanez tremolos.
The process of changing strings with a Pro Rock'r is somewhat akin to the method used for a steel-string acoustic guitar, with the pressure pads and their retaining screws playing the role of the acoustic bridge pins. The process should be something like:
- Remove the old string from the tuning machine by detuning and untwisting.
- Loosen and remove each of the pressure pad screws on the bridge which will release the ball end and allow you to remove the strings.
- Insert the ball end of the new string into the pressure pad hole.
- Insert the pressure pad with the groove facing the neck. Seat the pressure pad screw, and lightly tighten it down while lightly pulling up on the string to ensure the ball end is seated against the pressure pad. Important: the screw does not need to be torqued down tightly.
- Wind the string onto the tuner and bring the string to within a few semitones of pitch.
- Repeat steps 1–5 with the other strings.
- Tune all strings to pitch, starting with the outermost strings and working inward.
- Ibanez tremolo timeline, lawl.net, archived from the original August 2016