The 30ms Double Tracker happened to be next on our to-do list after the Keeley Abbey Chamber Verb and it turns out that they have a lot in common. Both are circuits inspired by the iconic Abbey Road Studios, and meticulously designed to give you authentic sounds and precise control. One of Abbey Road's pioneering efforts in the 60's was automatic double tracking, which made voices and instruments sound rich and dimensional. Studio Engineer Ken Townsend was asked to create ADT specifically for the Beatles, who liked to sound created by double tracking but hated the tedious manner in which it had to be done. By oscillating the speed of a second tape recorder and playing it back in sync with the original vocal or instrument, the sound image grew to mimic a true double track/chorus effect.
What Keeley did with the 30ms Double Tracker is give you the power of ADT for live performance along with three different operation modes and Mono/Stereo inputs. There are 4 main controls on the 30ms DT and a mini toggle for each mode. Here's the breakdown:
Dimension - This mode produces two slightly detuned voices, which you can pitch control using the TUNING knob.
Abbey Mode - This is the "authentic ADT" sound of Abbey Road in the 60's. It is a single delayed voice with modulation that emulates a tape machine being manually slowed down.
Slapback - Adjustable slapback delay with a range of 30ms-120ms as well as moveable doubled voices.
That being said, Keeley loves options so the knobs have different functions depending on what mode your in as well as internal dip switches that engage the Double Tracker Pro Mode. The Pro Mode simply deactivates the Reverb function in favor or individual tuning of the double voices. This is a really neat touch that really lets you find your own unique sound with the double tracker. Each unit comes with a TRS Stereo Cable so you can get right into the deep stuff without buying any more equipment. The Keeley Double Tracker Pro is another piece from Keeley that gives "studio grade stompbox" a whole new meaning.