These new lightweight Sledgehammer tuners from Korg share a wide- jawed plastic clip and fully rotating tubular head.
The Sledgehammer has a recessed flat screen with thumbwheel controls at each end. The left wheel, moved up, turns the power on; turned down, you select chromatic, guitar or bass modes.
The right wheel, moved up, calibrates the tuning reference from 436-445Hz; moved down, you enter the flat (down five semitones) or capo (up seven semitones) modes.
On its rounded '3D' display, the all-black Pro has a choice of read-outs (regular, strobe and half strobe) but does away with the specific guitar and bass modes. It has improved accuracy(+/-0.1asopposedto +/- 1 cent) and increases battery life from eight to 14 hours.
Accuracy and quick response here are extremely good. The standard Sledgehammer's more basic display is better for students; yet it's a little slower and seems very slightly less accurate.
The Pro, however, especially in strobe mode, is on a par with a Peterson Virtual Strobe - we achieved excellent results with both a troublesome nylon string and gigging a bass.
Accurate and lightweight they may be, but both are on the steeper side, price-wise, of the clip-on tuner market.
The Pro, however, is the most accurate tuner of its type we've yet encountered, and the most visible, in terms of that '3D' display.