I figured this belonged in the common questions topic area because I've seen these questions come up quite often. *I'm sure the moderators will move this thread if they agree. *Apparently, mere mortals are not permitted to post there. *

*
Anyway, I was shopping for some fret dressing tools at Stew-Mac when I saw an ad for a new book from Dan Erlewine, luthier extraordinare. *It's called "How to Make Your
Electric Guitar Play Great." *I popped over to Amazon to order it and it arrived today (Stew-Mac's price was a little high, but if you order soon, your copy will be signed by Dan himself!).
Beginning on page 77 is an entire section devoted to Floyd Rose systems using Ibanez trems as an example. *Erlewine interviewed Jim Donahue of Ibanez, Bensalem for this section and much of it quoted directly from Jim. *So, in flagrant violation of copyright law (probably not, because I'm not selling this info -- but I'm not a copyright lawyer *

), here are some excerpts that I thought might finally help to answer some questions (or perhaps add fuel to the fire). *Specifically: *what is the difference between the original Edge and the Lo-pro?; Is it okay to adjust the trem posts at full string tension?; and what is the proper configuration for the trem springs (arrow or straight)? *Enjoy!
Page 77-78:
* * Ibanez is a good guitar for demonstrating setting up a
locking tremolo system because many of the world's greatest rock guitarists and hard-diving tremolo users play Ibanez models equiped with the EDGE Floyd-Rose licensed tremolo system. *I talked to Jim Donahue, Director of Quality Control and R & D for Ibanez Guitars in the United States at his office in Bensalem, Pennsylvania. *A 16-year Ibanez employee, Donahue first worked in the repair and setup shop where he set up thousands of Floyd Rose locking trems. *If you can set up and adjust the Ibanez EDGE, built after the original Floyd Rose design, you'll be able to handle any other locking tremolo.
* * I asked Donahue how the EDGE differs from the lower-profile Ibanez tremolos, such as the LO-TRS and the LO-PRO EDGE.
* * *"On the low-profile models, the fine tuners are lower, more parallel to the top, and less in the way. *You can palm the bridge with less chance of the strings going sharp, and your forearm has more freedom. *The EDGE, however, because the fine tuners angle upward more, allows for far more up-pull than the other models; because of the up-pull, we install a Block Lock to keep the springs from popping loose during heavy up-pull. *The EDGE models have a different feel and sound than the others, too. *The LO-PRO EDGE also has the Block Lock because it too has more up-pull than other Ibanez tremolos
(not as much as the EDGE does, though). *The LO-PRO has good up-pull because the body cavity is routed deeper on models equipped with it.
Page 79:
IS IT OKAY TO TURN THE HEIGHT-ADJUSTING PIVOT STUDS UNDER STRING TENSION?
* * "Yes. *It won't harm the knife edges at all. *However, the EDGE and LO-PRO EDGE have pivot screws with secondary stud lock screws on their bottoms. *Always loosen these screws (counterclockwise) and back them into the main pivot screw while making a height adjustment, then retighten the stud lock screws. *These stud lock screws are a deluxe feature and provide extra stability and better coupling on these higher-end tremolo models."
Page 80:
WHY DO PEOPLE SLANT TWO OUTSIDE SPRINGS TOWARD THE CENTER?
* * "Some good player (it may have been Jimi Hendrix) probably installed the springs that way, people saw it, and the fad started. *There's no good reason, from a spring-tension point of view. *However, if you have big hands like guys like Jimi and myself, it's hard to get your fingers in there to install the springs along the tremolo cavity wall. *I'll bet that's how it started."
Page 65:
* * Before beginning my research to write this book, I'd always felt that the [tremolo] springs (whatever number) should run in a straight line so that they stretch equally and have the same tension and sound. *That is how I've installed them for years. *I figured that players who angled the two outside springs toward the center, rather than in a straight line, had big fingers and couldn't install the springs along the edge of the tremolo cavity (and it's not easy unless you have the right tool).
* * ....
* * Now, however, after speaking with respected builders and repairmen while researching this book, I am re-evaluating my opinions and trying some new approaches. *For example, Tom Anderson's viewpoint is quite different from what I have been thinking:
* * "I use three springs, and I like them to be opened up some, and never want them closed--open enough that even with the arm pulled back, the springs remain open. *I angle the outside springs to the center because I like a relatively stiff feel when I push the arm down. *The two springs angling to center are already exerting almost enough pressure to balance the strings by themselves. *This produces a smooth, cushy feel because the more a spring is open the less resistance it has. *As you push down, the angled springs give easily, and the almost-closed middle spring, which is carrying very little of the string tension, offers the resistance that adds a stiffness that I like."
I thought this was all very interesting, especially the part about the original Edge having more of an up-pull range than the Lo-pro. *To my mind, that explains why Satch and Vai seem to prefer the original Edge.
In any event, this book is pretty good for those of us who aren't setup and repair geniuses like Rich
J