Inspired by Brian Eno’s Music for Airports (particularly the vocal looping used in track 2/1) and a question posed on r/ZOIA by u/swgazer, airport loops is a patch designed to be a miniature loop manipulation/mixing console for creating evolving textures and compositions.

V2 has two forks: ‘airport loopSV2’ and ‘airport loopsV2.’ The capital S in the first fork stands for stompswitch or sync (or both).

STOMPSWITCH RECORDING and MIDI RECORDING SYNC (_airport loopS only_)! On the front page are two pushbuttons “STOMPSWITCH REC” and “MIDI CLOCK.” Pressing the first, Stompswitch rec, will allow you to record from the stompswitches. While the button is enabled, the left and middle stompswitch are repurposed as:

Left, momentary — steps through the loop buffers

Middle, momentary — records the selected loop buffer

If the pushbutton MIDI Clock is also enabled, the recording will begin and end in time with the MIDI clock received. Note: loops will drift, especially as they are manipulated. It is best to think of this feature as a way to capture a bar or some other clock-defined musical phrase, rather than as a way to sync loops to a clock in perpetuity.

If this is the only difference, why fork at all, you might ask? One, when the tape age is used, CPU increases just enough that adjusting the tone control (see below; based on multi-filters) clips the CPU a little, resulting in cracks and pops; the CPU saved from omitting the stompswitch recording and sync controls provide enough cushion to avoid this (as far as I can tell). Two, a lot of people asked for these changes, and I am happy to oblige, but this isn’t how I, personally, use the patch, and I would rather avoid the additional clutter.

GLOBAL MACROS (both forks)! On the first page, you will find global macros (affecting all loops simultaneously) for: LEVEL (-/+), TAPE SPEED (-/+), TONE (-,+; this is a tilt EQ, based on the tone module from the effects section), TAPE AGE (+), and CORROSION (+; this is an AM-based distortion, which modulates the loopers’ VCAs with a random/noise module. It is akin to the FM distortion, created by the Tape age control, but it affects amplitude, rather than frequency).

The macros are additive, rather than proportionate. In other words, if you have four loops with levels .9, .5, .5, .5, and increase their level using the macro, they will rise to 1.0, .6, .6, .6, then 1.0, .7, .7, .7, etc.

TRACK AND HOLD TAPE SPEED CHANGES (both forks)! When you press the previously-unassigned RIGHT STOMPSWITCH, the current tape speeds will be held. While holding the stompswitch, you can adjust the tape speed of one or more loops, and when the stompswitch is released — and only when the stompswitch is released — the loop will change to the new speed. This makes it easier to dial in specific changes of pitch/speed without passing the sweep from one speed to another.

SLIGHT ADJUSTMENT TO TAPE AGE CONTROLS! The control has the same range as before, but it now scales exponentially, rather than linearly. The most useful output of the tape age control for me was found between 0.00 and 0.05 in the previous scaling; this is where a subtle flutter distortion lives. The new scaling makes those sounds easier to dial in and explore the nuances of, while still preserving the mayhem of more all-out tape distortion. Win-win!

MINOR UNDER THE HOOD IMPROVEMENTS! Woo!

I want to thank all the people who’ve given such positive feedback to this patch. It seems like the sort of thing that maybe isn’t for everyone, but the people who dig it (including myself), really dig it.

============ Original patch notes ==================

Four loops can be recorded asynchronously, or a single loop can be recorded simultaneously to each loop buffer for further manipulation. (This allows for combinations of synchronous and asynchronous looping, as a loop could be recorded into all buffers, then buffers 3 and 4 could be recorded over, leaving 1 and 2 as synchronous loops from the same source, while the others differed.)

Once recorded, the control page allows for a wide range of manipulation techniques, including adjusting the speed/pitch of the loop, its playback direction, the start and stop points, and an FM-inspired “tape age” control for adding flutter and distortion.

The loops can also be mixed, sent to a reverb lite, and panned.

The signal path sums to mono, but outputs in stereo (through the reverb lite and panner). There is also a stereo dry through.

Controls:

Stompswitches:

Left — maxes reverb decay; the slew limiter that controls the rise and fall of the reverb decay is located on page 2, as well as the reverb lite, if you would like to adjust the default decay of the reverb

Middle — mutes all live tracks, unmutes all muted tracks; this can be used to have loops fade in and out or to silence all of the loops (if all are live when the stompswitch is pressed)

Control pages:

Page 0: Recording

There is a pushbutton corresponding to each track. There is also a white pushbutton labeled “Record to all” that allows you to record to all the loop buffers simultaneously.

The pushbuttons are latching, but changing them to momentary would be easy, if you preferred.

The loop buffers are set to 32 seconds. If you exceed the buffer time, the loopers do weird things. In order to help with this, there is a countdown clock that runs across the top of the page. Pixels will appear when recording begins and slowly disappear when as it continues. When the last pixel disappears, 32 seconds have elapsed.

Page 1: Loop control

The controls are color-coordinated to each track.

The left and right side generally perform two separate tasks. The left side is loop manipulation. The right side is mixing.

The left controls are, per track:

“Tape speed” — pitch/speed control for the loop

Reverse — when pressed on, the loop will play in reverse

Tape trim — adjusts the start point of the loop

Tape length — adjusts the end point of the loop

Tape age — this is a control that modulates the loop speed with a random module; this will generate random numbers at a low audio rate (I forget; I think it’s ~250 Hz?), essentially FMing the loop. The effect of this is, at low levels (less than .0500), a sort of flutter vibrato, which as the tape age control increases becomes more and more distorted. A little goes a long way, but a lot goes a long way too, in terms of creating distorted textures

The right controls are, per track:

Mute — this is a button that will mute the track if it is live and unmute the track if it is silence; the intensity of the button when live reflects the level of the loop (set below). The muting process is automated, using an ADSR, allowing you to fade a track in and out without having to fiddle around with the level control. (See also, middle stompswitch)

Fade time — sets the fade speed of the muting; the ADSR used for this is linear, and the total length of fade can be 60 seconds, so a value of .1 will be 6 seconds, etc.; you can very slowly weave loops in and out of the mix

Level — sets the level of the loop

Reverb send — determines the amount of the loop sent to the reverb lite

Pan — post-send this determines where the remaining portion of the loop sits in the stereo field