Mix Bus: “Analog” Tape Flanging for DAWs

I’m intrigued by anything that combines my analog background with the digital playground. I suppose high-res digital recording formats are blurring any arguments over whether CDs sound better than tape or vinyl, but my ears still tell me there’s something different about iron oxide. Call it crunch. Call it saturation. Call it sweet! At the very least, it’s a sonic tool that has prompted many attempts to recreate it’s magic inside the digital box.

Take flanging. DAWs provide oodles of flange-like plug-ins, and we all know the trick of doubling a track and offsetting it to bend our ears a little. But only those who have heard true tape-based flanging know how sterile digital flanging is by comparison. Along with the distinctive sound of tape, the original methods for flanging depended on imperfection. Even when techniques evolved from dragging a finger on a tape reel to modulating the tape-transport speed, the key was still subtle speed variations that made the sound more organic.

So how can we achieve a flange effect that more faithfully reproduces the original analog sound with a DAW? The old method was to mix the output of two tape players playing the same sound while manually varying the speed of one. Try that in a DAW! However, if you happen to have a three-head tape recorder with vari-speed, why not emulate the original method?

Let’s Flange

We’re going to route two dubs of a track we’d like to flange through the tape recorder. The results can be output to mains, as long as you mute all other tracks, and listen only to the flange effect. (To hear the effect properly as you flange in real time, you must avoid monitoring the original track.)

  • Record a dub of the stereo track (the original track) you wish to flange through the tape recorder to a new DAW track (label it “FLANGEDUB.”)
  • Record a second pass of the original track through the tape recorder to another new DAW track (label it “FLANGEMOD”) while manually adjusting the tape recorder’s speed knob. Twist to taste. The true cool of the old analog method was hands on, expressive control. Maximum effect modulation will occur fairly close to the zero delay point as you turn the knob toward and away from it. You’ll hear the zero point when you pass through it. What does it sound like? Just listen.
  • When you are jazzed with the result, slip-align the flange tracks back in time with your original track.

A cool aspect of this whole flanging thing is how open it is to experimentation. Consider placing the FLANGEDUB track 180 degrees out-of-phase during the FLANGEMOD pass to discover its effect. Listen especially for the magic zero point where there is no delay, and cancellation occurs. Passing through this point so smoothly is not possible in DAW flange emulations. Try different signal routings. Add a third original track tape dub, and vary its delay. Don’t be afraid to make mistakes. The whole flange idea came from someone’s mistake a long time ago—a happy accident.

The Monitoring Dilemma

Bummer. Why can’t you listen to other tracks in the mix while you’re flanging? It’s the delay problem. Try making a cloned copy of the original material you are attempting to flange. Mute the original. Slide the cloned copy left by a pre-determined measure to compensate for the tape-head delay. By doing this in advance, you can use the time-adjusted bounce copy as your original while making flange track passes that are in sync with the project. Be careful with your routing, though. More tracks to monitor makes the operation more complicated. If you use the “DAW-to-Analog” trick often enough, it might be worth setting up a dedicated audio interface I/O pair to the tape recorder. Patch bay, anyone?

A Reel Life Suggestion

Many EQ readers may not have a reel-to-reel analog recorder to use. Consider cassettes. TASCAM (and other manufacturers) made high-quality cassette 2-track decks, as well as multitrack units with three heads and vari-speed. The prevalence of current digital recorders has driven the price of these used units way down. I have a sweet TASCAM cassette 8-track. If I record one stereo source to all eight tracks at once (four left and four right), I get pseudo 1/8" half-track. Okay—almost. But I do get added iron oxide real estate. I do hear some benefit (more saturation?) from the same signal on multiple tracks, but the real point is how to make best use of any old analog gear you happen to have lying around.

To help preserve the fidelity of the original track when using cassette bounces, you might try a time-adjusted DAW clone copy of the original track as your FLANGEDUB track, instead of a tape-recorder dub. There might be some differences in the resulting sound, as the FLANGEMOD track will not have exactly equal frequencies after passing through the tape medium. But the unpredictability will be consistent with the original discovery of flanging in the first place that resulted in weird, but friendly collisions of unequal phase. And we all have weird friends, right?