The Pitchblack is aptly named, an affordable none-more-black stage tuner – even the logos and legends are in dark grey so the only thing you'll see on a dimly lit stage is the large bright read out.
With simple in/out jacks, and large chromed metal chassis footswitch, it all seems over-easy but advertises 'true bypass' plus, next to the mains adaptor 9V input, is a second socket for power output allowing you to power up other 9V pedals but only to a max consumption of 200mA.
There's also a choice of four displays – meter, strobe 1, strobe 2 and mirror – and calibration control from 436-445Hz.
The GB-1 is a simpler affair, a battery-only 'pocket' tuner designed with a fold out jack plug that plugs into your guitar or bass.
It can't be calibrated but can be configured for flat tuning (1-7 semitones in half steps) and has a yellow flash light – ideal for those pitch black onstage moments.
The Pitchblack impresses with minimal noise or alteration of your audio path, very accurate strobe-like tuning (easily accurate enough for basic set-ups too) although instead of the display choice (meter, is fine) we'd have preferred a sweetened Peterson-style tempered mode.
The GB-1? It works and is a handy gimmick – ideal for quick backstage/in-front-of-TV tuning but that's about all.
The Pitchblack is a dead simple stage tuner of excellent accuracy and quality and at a sensible price.
The GB-1 is a handy pocket tuner that'll allow you to tune up while your Pitchblack is onstage on your pedal board! Hardly essential, it's a handy, very affordable accessory for the guitarist who wants everything.