By Jim Curtis, Omega Engineer
There are several ways in which a reel to reel analog tape flange can be achieved, but the basic premise is always the same. Two identical signals are combined, one of which is delayed by a small amount that gradually changes over time, then advanced in the same manner. This effect can be applied to individual instruments or entire mixes. The origin of this effect is a subject of debate but is probably most commonly credited to EMI recording engineer, Ken Townsend, best known for his work on several Beatles albums. Legend has it that, in 1966, John Lennon asked Townsend if he could create the sound of double tracked vocals without actually double tracking them. Townsend then developed a process he referred to as “ADT” – artificial double tracking – which he first used on the Beatles song “Tomorrow Never Knows.”
Let’s explore the details of flanging an entire mix:
- The mix is first transferred to 1/4” analog 2 track tape
- The output of the 2 track tape machine is then routed back to two open tracks of the multitrack
- The trickiest part is getting both versions of the mix (2 track and multitrack) synched for playback.
- Cue the tape on the 2 track to an obvious starting point – the downbeat of a measure usually works best. The downbeat of the first measure can be used relatively easily if there is a count-off to the song. If not, try to get as close to the beginning as you can.
- Initiate recording on the multitrack, then, using your best musical sense, begin playback of the two track on the downbeat that corresponds to playback of the multitrack. For example: cue the two track to the downbeat of bar 5, initiate recording on the multitrack from the beginning of the song, count through the first 4 bars then begin playback of the two track precisely at the moment the multitrack reaches the downbeat of bar 5. As long as you have a good musical sense…and can count to at least 5, playback of the two track should be closely synched to the multitrack.
- As the two track is playing, slow down the playback by resting your thumb on the supply reel. The idea is to slow down the playback so it shifts gradually out of time with the playback of the multitrack. This must be done somewhat delicately. Being done too aggressively can cause too far of a shift in time and a drastic change in pitch. This technique takes practice, but once perfected is well worth it.
- Once it has been pulled far enough out of time, usually about 20 milliseconds or so, it can be pulled back in the other direction. Using your index finger, force the take-up reel to go slightly faster – the direct opposite of what you did with your thumb on the supply reel. This will cause the flange effect to modulate in the opposite direction.
- Repeat this process until you have flanged all you intended to flange. Since the output of the two track was recorded to the multitrack, the effect can be brought in and out of the mix as desired.