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Category Archives: Friday Tip of the Week

Friday Tips: Create the “Barberpole” Audio Illusion

The Shepard Tone (aka Barberpole) is an audio illusion where a tone always seems to keep rising (or falling). You may have heard it before—to build tension in music by Swedish House Mafia, Beatsystem, Data Life, and Franz Ferdinand, as the sound effect for the endless staircase in Super Mario 64, for the sound of constant acceleration for the Batpod in The Dark Knight and The Dark Knight Rises, at the end of Pink Floyd’s “Echoes” from the Meddle album, or in the soundtrack for the film Dunkirk in sections where the goal was to produce a vibe of increasing intensity. Check out the audio example, and you’ll hear how the tone just goes on forever.


Thanks to Studio One’s Tone Generator, it’s easy to produce a Shepard Tone loop—just follow the step-by-step instructions, in a song with the tempo set to 120 BPM.


  1. Insert the Tone Generator in the Input L+R insert section so that you can record its tone, and edit the Tone Generator generator’s settings as shown in the screen shot. The goal is the longest possible sine wave sweep from 20 Hz to 22 kHz.


  1. Start recording, then click the Tone Generator’s On button. After recording the file, trim the beginning and end respectively to just before and just after you can hear a tone, and add a short fade in and fade out.

  1. As shown above, copy the track, and offset each track’s beginning by two measures compared to the track above it. Keep copying and offsetting until the start of the last track is at the same measure as the end of the first track.

  1. Now select all, and drag the entire group to the right so that there’s a bit of an overlap between the two groups. Select everything, then type X to turn the overlap into a crossfade with a linear curve. Next, create a loop that extends from the start of the lowest track to the end of the highest track.


  1. Choose Song > Export Mixdown, set the Export Range to Between Loop, and under Options, check Import to Track and Close After Export. Solo the mixed track, and play it—you’ll hear a continuously rising tone. Now we need to turn it into a loop.


  1. Follow the instructions in the July 27 Friday Tip of the Week on how to create pads that loop perfectly. The above screen shot shows the basic concept; Track 1 shows the first steps. Copy the clip, move the copy to the right so it overlaps the last four measures of the original clip, and then crossfade the overlap with a linear crossfade.


  1. Track 2 in the screen shot shows the next step. Bounce the two clips together, then split at the end of measure 4 to remove the first four measures, and at the end of the crossfade to remove everything after the crossfade. Loop the section that remains, and you have your never-ending upward Shepard Tone, as a glitchless loop. Note that when you bring it into a project, don’t stretch it to conform to tempo—there is no tempo. And if you want it to go on forever…just keep typing D!


Download the loop here!


Bonus Tips:


  • I recommend adding a Pro EQ—reduce the high frequencies somewhat with the HC (High Cut) filter, and boost the low frequencies with a bit of a shelf, to increase the illusion’s effectiveness.
  • The “classic” Shepard Tone requires that the tones be one octave apart. However, offsetting them by 2 measures at 120 BPM seems close enough.



The Virtual “How Does It Sound in a Car?” Tester

This tip is for those who won’t sign off on a mix until they’ve heard it in a car. There may be a scientific reason why this is beneficial: Noise tends to mask sounds, so if one instrument you want to hear gets lost in the noise and another jumps out, try a mix that raises and lowers those levels, respectively.

The ear doesn’t discriminate level differences as accurately as pitch differences, so without noise masking a sound, the level may seem okay. But as soon as you mix in noise, an important sound may disappear. If you increase the level just a bit so you can hear it, when you remove the noise there’s a very good chance you’ll like the new level setting better. Think of this as doing something similar to compression, but without applying any actual dynamics. You’re just making sure that the levels needing parity, have parity.

Of course this doesn’t mean you want everything jumping out of the noise—those tambourine and shaker parts are probably just fine as they are. The main sounds to listen to here are vocals, leads, drums, and bass, as well as their relationship to each other.

This also doesn’t mean you should mix consistently with noise, as it will bias your hearing (and besides, it’s truly annoying). I add noise in with a mix as a last diagnostic step. If the mix has sounded fine up until then and passes this final test, I consider it ready to master. And I don’t need to go driving anywhere, either.


Just follow the steps, and you’ll be good to go.


  1. Create a stereo audio track, and insert the Tone Generator effect. Turn the track’s fader all the way down.
  2. Choose Pink Noise as the waveform.
  3. Click On to start generating noise.
  4. Turn up the track’s fader to add noise to the mix.

One very cool aspect of the Tone Generator’s noise is that it’s true stereo where the left and right channels don’t correlate, so you don’t get any center channel buildup (as would happen with a mono noise signal).

As to how much noise to add, it’s kind of like maximizing. Set it 6 dB below the mix’s peaks, and you’ll hear what occupies the upper 6 dB of dynamic range. Set it 12 dB below the mix’s peaks, and you’ll hear what’s in the upper 12 dB of dynamic range. This isn’t an exact spec per se, but it provides a rough standard of comparison.

As crazy as this idea sounds, try it sometime and tweak your mix. Then turn off the noise, take a short break so your ears get acclimated back to normal hearing, and then check the mix again. I won’t be surprised if you hear an improvement!


Songwriting with Impact XT

This tip is for those of you who didn’t see my Studio One workshop at Sweetwater GearFest 2018, were turned away because of that pesky fire marshal’s rules about crowds, or who didn’t realize Studio One 4 has some pretty advanced looping capabilities—as well as the ability to trigger pitch transpositions for loops.

With Impact XT, you can load loops on pads, and then trigger them (on and off) in real time via MIDI notes. Assign each output from an Impact XT pad to a track input (in the screen shot, Track 5 is recording the output of Impact XT M4), set all the tracks to record, and you can record the results of your improvisations.

The following screen shot shows the results of recording the first part of a potential song. Note how some tracks have sounds that extend the length of the recording, while other tracks had their sounds brought in at specific times by triggering an Impact XT pad.

This by itself is pretty cool, because you can weave loops in and out to create an arrangement. The song goes longer than this, but the above shows what you’re hearing in the following audio example. Granted, it’s not much of a song—it just kinda drones on and on. But keep reading…this is just the start.

The process becomes far more interesting when you bring the chord track into play, because you can transpose the loops to create a chord progression that becomes the basis for a song. All the tracks, even the drums, were set to follow the chord track. Listen to how although some of the original loops added a fourth to the tonic, when this was synched to the chord track, all of the loops followed a tonic-to-fourth chord progression. In other words, it wasn’t just one loop adding a fourth, but the entire song transposing to the fourth. We also gained an intro; here’s the chord progression that was used.

And here’s what the chord progression sounded like after harmonic editing. The major difference is in the intro, and transposing to D to kick off the second half of each verse.

Working this way can be very inspirational because you can create a basic arrangement with loops, and then use the Chord Track to create a chord progression. Although PreSonus is careful to point out that Harmonic Editing is more for “prototyping” songs and they expect that you’ll want to replace the “scratch” parts, I’ve found that many times the scratch parts end up being keepers—and I gotta say, I love what happens when you tell drums to follow the chord track!

Friday Tip of the Week – Trolling for Slices

So there you are, with your shiny new Impact XT virtual instrument. You want to populate the pads with some fun drum sounds, and although you like the included kits, you’re itching to get creative and come up with some kits of your own. Fortunately, it’s easy to use Audioloops to populate your Impact XT with a custom selection of drum sounds.

Open the Browser, and under Loops, look for files with the .audioloop suffix. The reason why .audioloop files stretch elegantly is because the loop is cut into slices, with each slice representing an individual “block” of sound—kick, snare, clap, kick and cymbal hitting at the same time, snare and high-hat hitting at the same time…whatever.

When you expand an .audioloop, you’ll see each slice listed individually. Some have only one or two slices, but others—for example, the Combo Beat loops under Electronic > Drums > Loop (Fig. 1)—are rich sources of slices.


Figure 1:  The Browser’s Loop tab is loaded with slices, just waiting to be used with Impact XT to create custom kits.

Next, open up Impact XT. To audition the slices, toward the bottom of the browser turn off the loop and metronome options, select a slice, and then click on the Play > button. Click on various slices and when you hear something you like, drag it over to an Impact XT pad (Fig. 2). You won’t have to click the Play button again to audition slices until after you drag a slice over.


Figure 2: Drag slices over to Impact XT pads.

The real fun begins when you start to use Impact XT’s sound-shaping options. For example in Figure 2, one of the kick slices has been dropped in pitch, truncated, filtered, and given a new Amp decay setting to sound more like an explosion. Note that the pad’s name will be the same as the .audioloop, so if you’re using multiple slices from the same .audioloop, rename the pad to avoid confusion (right-click on the pad and choose Rename).

And remember, you’re not limited to dragging over slices from the Browser—you can split any file in the Edit window at the Bend markers, and drop those slices into Impact XT.

Sure, Impact XT comes with a lot of preset, ready-to-go kits when you just want to load something and start grooving. But you might be surprised how doing a little mixing and matching with the Browser slices can create something new and different—and each new pad sound is only a click + drag away.




Friday Tip of the Week – EZ Squeez: the One-Knob Compressor!

Sometimes you just want a compressor that’s quick and easy. Maybe you’re tracking and need to compress the vocals, or hear what the bass will sound like when you add some compression on mixdown. But you know what happens—you adjust the threshold, and then the ratio, but now realize you need to re-adjust the threshold, which means the output gain needs adjusting…and maybe the knee…

If you have a bunch of ready-to-go presets, great. But here’s another option: The EZ Squeez compressor. It uses an FX Chain macro to alter six compressor parameters at once, so that a single knob sweeps from no compression, to some compression, to compression that’s more like a guitar sustainer stompbox. Although there’s a downloadable preset, I’d recommend reverse-engineering this to learn the power of the FX Chain’s Macro Controls. The principles used in this FX Chain apply to many other processors.


Figure 1: Three different Macro Control settings.

Figure 1 (top) shows the compressor settings with the EZ Squeez knob turned all the way counter-clockwise (minimal compression). As you turn up the EZ Squeez control, the Ratio, Release, and Gain increase, while the Threshold, Knee, and Attack decrease. The middle image shows the EZ Squeez knob turned up about 60% of the way. Turned up all the way, the parameter values become more extreme, as shown in the lower part of the screen shot.

Figure 2: (Top) Macro Controls parameters and (bottom) Macro Controls interface.

Figure 2 shows the Macro Controls. Rather than expose the control settings, it’s easier just to download the Multipreset, and then click on the curves for yourself. Note the curves on the Gain and Release parameters. Given that there’s only one node on the curve you can’t get too sophisticated, but these are close enough to give a fairly even response as you move the knob from fully counter-clockwise to fully clockwise.

Because compressors are so dependent on the input signal level, I did cheat on the “one-knob” concept and added an input level control. This allows trimming the input level so that it falls in the compressor’s “sweet spot.” There’s also a bypass button so you can compare the compressed and uncompressed sounds.

As to applications, you’ll probably find that EZ Squeez knob settings of 30% to 65% will work for a variety of signal sources. Past that point, the compressor gets into a more extreme territory that pumps mixed drums, and acts more like a sustainer for guitar. But it’s easy enough to find what works the best—just turn the knob until the compression sounds right. After all, that’s the whole point!

Download the EZ Squeez.multipreset




Friday Tip: Delay-Free Stereo from Mono

After a recent tip on how to extract two mono tracks from a stereo track, one of the comments asked for how to convert mono into stereo. Well, we aim to please…so here’s one option.

A common way to create stereo from mono is by duplicating the track, delaying one of the tracks compared to the other, and panning them left and right. However, this approach has two problems. First, you might not want a delay. Second, when you collapse the signal back to mono, there will likely be partial cancellation due to phase differences. The method we’ll cover here not only produces stereo imaging from a mono source, but collapses perfectly to mono. It works with pretty much any instrument, but is most effective with instruments that play chords (for example, try this on acoustic guitar—it works well).

Console Setup

Create two buses. One of these will become the left channel, and the other, the right channel. In your mono source track, create two pre-fader sends (one for each bus). Turn down the mono source’s fader.


Multiband Dynamics Setup


Insert a Multiband Dynamics into one of the bus inserts. Solo the bus with the Multiband Dynamics. Click on “Edit All Relative” and set the Ratio control to 1.0. This will set all bands to a ratio of 1.0, which converts the Multiband Compressor into a multiband EQ.

Play the track you want to convert to stereo. Solo each band in the Multiband Compressor, and adjust the frequency sliders to divide up the frequency response evenly over the five bands (the screen shot shows frequencies selected for dry electric guitar). Mute bands 1, 3, and 5.

Next, drag the Multiband Dynamics into the other bus’s Inserts slot. For this bus, mute bands 2 and 4 instead of bands 1, 3, and 5, then pan the two buses left and right. Now the frequency responses are equal and opposite for the two buses. Voilà! Stereo! (Note that you probably don’t want to pan the buses too far to the left and right, because the stereo effect will be unrealistically exaggerated—as in the audio example. But it does get the point across.)


We’re not done yet, though. The levels of the two buses will be fairly low because with only two or three bands, the output level will be down quite a bit. Turning up the bus faders may be sufficient to compensate, but if not, turn up the Multiband Dynamics processors’ master Gain controls (not the per-band Gain controls). Feel free to play around with the pan and Gain controls to achieve the desired sonic balance. Also, no law says you need to mute every other band. For example, you might want a bassier sound on the left by muting the three upper bands, and a brighter sound toward the right by muting the two lower bands.

Finally, note that when you toggle the master bus from stereo to mono, the sound collapses to mono without any funky phase interactions. Done!

Friday Tip: Rotating Speaker Emulator FX Chain

A rotating speaker is an extremely complex signal processor (as most mechanical signal processors are—like plate reverbs). It combines phase shifts, Doppler shifts, positional changes, timbral variations, and more. And of course, Studio One includes the Rotor processor, which does a fine job of capturing the classic rotating speaker sound.

However, I’ve always felt that rotating speakers have a lot more potential as an effect than just emulating physical versions—hence this FX chain. By “deconstructing” the elements that make up the rotating speaker sound, you can customize it not only to tweak the rotating speaker effect to your liking, but to create useful variations that don’t necessarily relate to “the real thing.” What if you want a speed that’s between slow and fast? Or a subtler effect that works well with guitar? Or simulate the way that the horn spins faster when changing speeds because it has less inertia than the woofer? This FX chain provides a useful, more subtle variation on Rotor’s rotating speaker sound—check out the audio example—but the best way to take advantage of this week’s tip is to download the multipreset, roll up your sleeves, and start playing around.

Rotating speaker basics. There are two rotating speakers—one high-frequency driver, and one low-frequency drum. A crossover splits the signal to these two paths, so we’ll start the emulation by setting the Splitter to Frequency Split mode around 800 Hz. Here’s the routing.

The high-frequency and low-frequency paths each go into a Flanger to provide Doppler and phase shifts, and an X-Trem for subtle panning to provide the positional cues. Let’s look at the individual module settings.


The Analog Delay adds a 23 ms reflection for a bit of a room sound vibe, with some modulation to add a Doppler shift accent. Finally, an Open Air reverb (using the 480 Hall from Medium Halls) creates a space for the rotating speaker.

Knob Control. This was the hardest part of the emulation, because changing speed has to alter (of course) Flanger speed, but also the Flanger’s LFO Width because you want less width at faster LFO speeds. The X-Trem speed and Analog Delay LFO speed also need to follow the range from slow to fast.

However, the curves for the control changes are quite challenging because the controls don’t all cover the same range. Fortunately you can “bend” curves in FX Chains, but you can’t have more than one node. As a result, I optimized the knob settings for the lowest and highest speeds—besides, a real rotating speaker switches to either speed, and “glides” between the two settings as it changes from one to the other. An additional subtlety is that the high-frequency “speaker” needs to rotate just a little faster than the low-frequency one. Also, they shouldn’t track each other exactly when going from the slowest to the fastest speed because with a physical rotating speaker, the low-frequency drum has more inertia.

All these curves do complicate editing any automation, because you need to write-enable each parameter when you turn the knob. So if you need to change some automation moves you made, I recommend not trying to edit each curve—just try another performance with the knob.

Oh, and don’t forget to try this on instruments other than organ!



Listen here:

Friday Tip: Smoother, Gentler Sidechain Gating

I’ve always been fascinated with using one instrument to modulate another—like using a vocoder on guitar or pads, but with drums as the modulator instead of voice. This kind of processing is a natural for dance music, and using a noise gate’s sidechain to gate one instrument with another (e.g., bass gated by kick drum) is a common technique.

However, the sound of gating has always seemed somewhat abrupt to me, regardless of how I tweaked a gate’s attack, decay, threshold, and range parameters. I wanted something that felt a little more natural, a little less electro, and gave more flexibility. The answer is a bit off the wall, but try it—or at least listen to the audio example.


Setup requires copying the track you want to modulate (the middle track below), and then using the Mixtool to flip the copy’s audio 180 degrees out of phase (i.e., enable Invert Phase). This causes the audio from the original track and its copy to cancel. Then, insert a compressor in the copy, and feed its sidechain with a send from the track doing the modulating. In this case, it’s the drum track at the top.



When the compressor kicks in, it reduces the gain of the audio that’s out of phase, thus reducing the amount of cancellation. However, as you’ll hear in the example, the gain changes don’t have the same character as gating.

You can also take this technique further with automation. The screen shot shows automation that’s adjusting the compressor’s threshold; the lower the threshold, the less cancellation. Raising the threshold determines when the “gating” effect occurs. Also, it’s worth experimenting with the Auto and Adaptive modes for Attack and Release, as well as leaving them both turned off and setting their parameters manually.

Using a compressor for “gating” allows for flexibility that eluded me when adjusting a standard noise gate. If you want super-tight rhythmic sync between two instruments, this is an unusual—but useful—alternative to sidechain-based gating.

Friday Tip: Perfect Pads!

Pads that Loop Perfectly—Yes, It’s Possible!

Pads are hard to loop, because their flowing, continuous sound exposes loop points that are anything less than seamless—there will often be a click, pop, or other glitch. But there is a solution, so keep reading for how to create perfect loops for just about any pad.

Step 1. Record a pad that’s one measure longer than what you want to loop. For example, record five measures to create a loopable four-measure pad. Normalize, then reduce the level by -3 dB or so to accommodate peaks that may result from later crossfading. Then, bounce the clip to itself to make this level change permanent.

Step 2. Copy the clip, and then paste it (or alt+drag the clip) so the first measure of the copy overlaps the last measure or the original clip. In this example, the overlap extends across measure 5.

Step 3. Shift+click on the original clip and the copied clip so they’re both selected, then type X to create a crossfade. Move the crossfade nodes up to create a logarithmic fade.

Step 4. With both clips still selected, bounce to create a single clip. Split at the end of the first measure and at the end of where the clips overlapped (in this case, measure 6). Delete both ends so what’s left extends from the start of measure 2 to the end of measure 6. Bounce what’s left to itself, loop it, and you’ll hear a perfect 4-bar loop.

Note: In some particularly challenging cases, you may need to overlap the clip’s first two measures over the clip’s last two measures to create a suitable crossfade. However, if the pad is relatively consistent you almost certainly won’t encounter any issues.

Friday Tip: Reverb Chord Progressions? Why Not!

The more I play with Harmonic Editing, the more I find it can do things I never expected. Check this out…
One very useful Studio One feature is being able to record a track output into another track’s input. I take advantage of this sometimes by recording effects like reverb or envelope filter (set to effect sound only) into a track. This allows using Inspector features like transpose and delay, as well as have easier control during the mix.


So imagine my surprise when I set the reverb-only track to follow the Chord Track—and ended up with a tuned reverb chord progression! The following audio example gets the point across. The first four measures have the original reverb sound, the second four measures have the reverb processed by the Chord Track…pretty amazing.



There’s one caution: The only Follow chords mode that works for this is Universal. The Tune Mode doesn’t seem to matter, so I just use Default.


Extra bonus coolness tip! Drums can follow the Chord Track, again in Universal Mode, for a “drumcoded” effect (i.e., similar to drums “vocoding” something like a pad). Although there’s no way to do a wet/dry balance of the melodic and non-melodic components, you can copy the track, have only the copy follow the Chord Track, and adjust the mix between the dry and Chord-Track-following track.


The mind boggles.