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Checkpoint SA-S P-770 laser alignment tool
In a sidebar to his review of the B&W DM302 speakers in the October 1997 issue (Vol.20 No.10), Wes Phillips mentioned a handy tool he uses for speaker setup—a laser level. The one Wes used was originally intended for construction work, not tweaking one's speaker placement, but now there's one available specifically for that purpose: The 770 SA-S Laser Sound Alignment System by Checkpoint Laser Tools.
Much like the anonymous one used by Wes, this cool tool consists of a torpedo bubble-level precision-machined out of aluminum, with a miniature laser that shines its beam out of one end. Wes used his level by placing it on the side of the speaker cabinet, which resulted in a beam projected parallel to the cabinet wall, toward the listening area. That's pretty good—but what if the sides of the speaker aren't perpendicular to the baffle? Also, it takes a steady hand and attention to detail to use this kind of placement in a precisely repeatable fashion. (By the way, Wes is just that kinda guy.)
The 770 SA-S offers some help for these potential pitfalls by adding what they call an "alignment switch." It's called a switch because you turn the laser on by screwing it into the opposite end of the level. The unthreaded end of the alignment switch has a brass disc about the circumference of a half-dollar. You hold this disc against the front baffle of your loudspeaker much as a doctor places the cold disc of his stethoscope against your chest, et voilà—the laser beam is projected exactly perpendicularly to the baffle. (For those speakers without flat, vertical baffles, the 770 SA-S can also be used exactly as Wes described.)
If the thought of taking a drill to your speakers doesn't make you weak in the knees, you can also get magnetic discs that you can mount to the baffle via one small screw each. Having done so, you turn on the Magnetic Alignment Switch—same as the regular 770 SA-S, but with strong rare-earth magnets included—and stick that laser right on the speaker. This allows for exact repeatability when checking alignment, lets you move the speaker while the beam is still, er, beaming, and gives you the opportunity to play the speaker with the laser attached; doing so,you can see how much the laser jumps around and thus get a rough idea of just how solid the speaker cabinet/mounting is. Loudspeaker manufacturer M&K are designing products with the magnetic discs already included; Checkpoint is working with other speaker companies to offer similar arrangements.
So how does it work? Like a champ! I set a chair with a tall, broad backrest behind my listening seat; the backrest area covers roughly the same vertical area as my head. Using a pair of Joseph Audio RM-7si minimonitors, I found a spot mid-baffle where I could wedge the alignment switch against one of the grille attachment plugs, with the high point of the switch flush with the top of the cabinet. This "wedgeability" guaranteed that I could go back to exactly the same place—on both speakers. As a bonus, the chosen location was pretty close to that most directional of drivers, the tweeter.
I then jockeyed each speaker until the red dot was projected onto the outside edge of the chair backrest. (Joseph Audio doesn't recommend much toe-in; that's why I aimed for the outside.) I also adjusted one speaker to bring it into vertical alignment with the other. Using a bubble level atop each speaker had shown them to be pretty much true; with the laser spot projected on to the wall several feet away, any vertical discrepancies were magnified.
I sat down to listen, but before the first note played I noticed that the speakers sure as heck looked equally toed-in. Trying to do toe-in by eye has usually been a lengthy, frustrating experience; using the 770 SA-S, it took about a minute. If you'd expect that imaging would improve after such precision alignment, you'd be right. Not only were instruments and voices more solidly placed, but the space around them also had greater verisimilitude. But wait, I'm beginning to sound like a reviewer. This is "Industry Update."
Suffice it to say, from this day forward I won't set up speakers without the 770 SA-S. It lists for $139; the P-770 SA-S, the "pro" version, includes a bulls-eye vial switch and a way-cool carrying case, and will set you back $169.
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