In this article, Julian brings together our pick of the best modulation effects out there, and complains repeatedly about using chorus on bass…
I’ve always had a complex relationship with modulation effects. I was in my teens in the 80s and the legacy of Andy Summers’ guitar sounds was rife. The blue Boss CE 2 pedal was ubiquitous and with chorus all over bass sounds of the time, for me modulation was chorus.
While some people were completely on board with the (over) use of chorus through most of a decade I found the sickly swooshiness was something that quickly grew tiresome. However there is so much more to modulation than just chorus, and the 80s were a long time ago, I’ve got over it…
Here are 5 modulation plugins that we feel represent the best of what’s out there.
Modulation means change over time and when talking about effects usually, but not always, this refers to cyclic changes which repeat regularly in some kind of up/down, in/out fashion.
The original modulation effect was vibrato, a good singer uses vibrato to add interest and when done well it is an indispensable feature of the performance. Not all singers do it well and vibrato which is too heavy, slow or crosses over too far into tremolo can be distracting and unpleasant. The thing about “real” vibrato is that it modulates in a regular but not identical way. It is applied with variation making it slightly unpredictable. When any modulation starts to sound mechanical and predictable its effect is in danger of becoming more irritating than flattering.
Nowhere is this more in evidence than with vibrato. Automated vibrato effects are too predictable and mechanical for my ears. There are however other ways to introduce some wobble to your sound which can sound great.
Leslie - PSP L’Otary 2
The Leslie speaker cabinet is the granddaddy of modulation. Part vibrato, part tremolo and with dizzying complexity introduced by the interaction between the cabinet and the room into which it throws the sound, this is a simple idea with infinitely complex results.
In brief, a Leslie cabinet is the dedicated speaker cabinet which is designed to accompany a tonewheel organ. It has a high and a low frequency driver. The HF driver horn rotates at speed, imagine putting a trumpeter on a swivelling office chair and spinning him or her round - you get the idea. The bass driver is mounted in a drum with a baffle rotating in the opposite direction to the HF driver. The speed of these motors can be controlled from the organ and the effect is as rich and unpredictable as the Leslie cabinet is impractical and untransportable. I’m sure they were only tolerated for so long by gigging musicians because they were lighter than the organ that went with them!
Disagreements between Leslie aficionados over who manages to do the best job of reproducing this effect in software form are rife and as intense as discussions over guitar amplifiers but if running an audio track through the external input of DB33 isn’t doing it for you (if you haven’t tried this give it a go - great fun) then L’Otary from PSP is a great place to find a more purposeful implementation of the venerable Leslie effect.
As well as the essential controls for speed, it offers separate controls for Inertia, meaning how quickly you go from fast to slow and back again. These speed changes are so important to this effect that you need to be able to get them just right. Mic options, drive and a Stop Mode make this a complete solution but it wouldn’t mean a thing if it didn’t sound good, luckily it does so even if organ isn’t your thing, try out some Leslie. It’s an addictive sound. From Hendrix guitars to Pink Floyd Pianos this is all over recorded music but it has to be right to hit the spot.
Tremolo - Goodhertz Trem Control
In spite of the misnomer the tremolo arm received in the early days of Fender, tremolo is a modulation of amplitude, not pitch. I love tremolo. Where many reach for chorus or phasers on electric pianos, I’ll always reach for tremolo and on clean electric guitar it just adds instant Americana cool.
Once the appropriate depth and rate of your tremolo is set, something which really lifts tremolo is having control over the shape of the modulation. If you want to get in on some tremolo experimentation then try the free Adam Monroe Tremolo which offers different LFO shapes for amplitude modulation and panning. Did I mention that good tremolo has to be stereo?
However I’m going to recommend Trem Control from Goodherz which in one of the few places you can create Harmonic Tremolo. Harmonic Tremolo is a style of tremolo where as the high frequency information reduces in level, the low frequency goes up and vice versa. This is a very cool effect and one I drove myself slightly mad trying to create using stock plugins in a free tutorial some years ago.
Check out this overlooked sound which used to be available on old Fender amps but seems to have been largely forgotten and if you like it then this and any of a plethora of other tremolo effects are available using Trem Control.
Chorus - Arturia Chorus JUN-6
No discussion of modulation effects is complete without chorus and however much I avoid chorus, there are many people who enjoy it (even is some of them insist on using it on bass…). I think it’s the defocusing effect it has on sources like guitars and the slightly drunken tuning too much chorus introduces which offends me - don’t get me started on early 80s records which tried to use chorus to disguise poor intonation on saxophones!
If you want inoffensive, general purpose chorus I’d look to any of the many excellent emulations of the Roland Dimension D from the likes of UAD. However somewhere where swooshy chorus is very appropriate is thickening up synth sounds. I owned a Juno 106 for many years and the chorus installed in this synth has become revered by many as a classic. It sounded nice, though it was comically noisy. If you want a good plugin version of the Juno Chorus you can get a free version by trying the TAL-Chorus LX which with its I and II buttons offers all the facilities found on my Juno. If you want a more tweakable version with a flexible Manual mode with control over rate, depth and phase we recommend the Chorus-Jun6 from Arturia.
Phasing Vs Flanging
There is a persistent confusion about the distinction between Phasing and Flanging. This is because they both started as alternative names for the same effect. Tape phasing/flanging was an iconic effect of the late 60s (think of “Itchycoo Park”) which was created by feeding identical audio to two tape machines and varying the speed of them relative to each other causing comb filtering due to destructive interference or “phasing”. In his article 3 Ways To Create Lo Fi Sounds Using Stock Plugins Luke Goddard gives an excellent explanation of how to create this effect.
The reason for the confusion is that, because real tape flanging/phasing was cumbersome to create, other methods for creating these effects were born. Notably by Eventide who created the Instant Flanger and Instant Phaser hardware effects. These names came to denote the two alternative approaches used. Delaying the signal using bucket brigade delay circuits or using all pass filters. Both gave effects which were similar to the original but created two ways of achieving the same goal.
Our own William Wittman can be found blaming Eventide for creating this confusion in this short video from the Eventide website
Phaser - Eventide Instant Phaser
If we’re looking for a phaser effect which captures this divergence from tape techniques we might as well go to what is purportedly the first studio phaser, the Eventide Instant Phaser plugin is a recreation of the hardware box from 1972 and is as much about the irregularities of the analogue components of the day as it is about the phasing effect. Things which definitely set this apart from the stock phasers most DAWs feature is the Age control which dials in the decades of drift into the modelled components, and the four methods of controlling the phasing from standard LFO control to manual.
This style of phasing works using all pass filters, which produce different phase rotations at different frequencies, a different approach from using a delay.
Flanger - Softube Fix Flanger
To illustrate the other side of the phasing/flanging schism, rather than feature the equally significant Instant Flanger from Eventide, the counterpart to the Instant Phaser and coincidentally William Wittman’s software product of 2020
I’m going to go with the Fix Flanger from Softube. This is a re-creation of a hardware unit designed by Paul Wolff in 1979 and it is included here over the many alternatives because as well as sounding suitably thick and analogue, it includes a manual mode for controlling the relative speeds of the virtual “tape machines”. If you want a cyclic, LFO-driven flange then you can have that but the real fun starts when you play with the big knob in the top right. Controlling the plugin in manual mode and using the Flange Null display you can tease the audio to advance or drag behind itself and get that gorgeous through-the-null “suck” which you only get with through-zero effects.
It’s hard to do and unpredictable, which is what makes it fun. Map to a knob on your controller and lose a few hours to experimentation.
That’s our pick of modulation effects. There are loads we didn’t cover but these are our favourites. What would you have included?