Delay Tactics

Essential effects tips and techniques

Of all the various studio processors, delay is one of the most widely used. From a thickening vocal slapback to an echoey synth line, you’d be hardpressed to find a modern record that doesn’t feature delay or repeating treatments. The humble echo’s ubiquity can be attributed to its versatility. At the mixdown stage, adding delays to a signal can provide everything from subtle widening and mix thickening through to virtual ambience and even ‘glue’ to bind together multiple sounds in a mix. And if you’re more into sound design or composition, delay can provide your creations with overt rhythmic purpose, squealing feedback loops, custom chorus/flanging/phasing, and myriad other creative purposes.

However, while you might think it’s just a case of cranking up the feedback and setting the delay time, you require a firm foundation of knowledge to squeeze the most out of this particular effect.

Back in time

For the uninitiated, a delay device stores an incoming signal in its buffer, then plays back a repeat of that stored signal after a predetermined interval. Initially designed to emulate the echoes heard in everyday life, and famously used to create the short ‘slapback’ guitar effect that defined the

Rockabilly sound in the ’50s, the first studio delay effects used magnetic tape to record the incoming signal and play it back at a momentary interval. Under the hood, an ‘endless’ tape reel is continuously looped, then the incoming signal is recorded onto the tape via a record head and played back by several playback heads. By altering the tape speed or distance between heads, the time between repeats could be changed, with the former process creating a trippy pitchbending effect synonymous with classic tape delay and early Dub Reggae effects. As the tape degrades over time, the delays become ‘aged’, unstable and more lo-fi, giving tape delay its distinctly wobbly, dark sound that’s so sought after in the modern age of full-frequency digital delays. Famous hardware tape delay units such as the Echoplex (1959), Watkins Copicat (1960) and the Roland RE-201 Space Echo (1973) are still highly sought-after on the secondhand market.

As ’70s technology advanced, the ‘bucket brigade device’ (BBD) gave birth to the solid-state delay pedal as we know it. This small BBD circuit could store just enough of a signal to generate convincing echo effects, and could be fitted inside a smaller, more convenient, battery-powered chassis such as a stomp box, giving birth to the ubiquitous guitar pedal suitable for the touring guitarist’s gig bag. BBD echoes are characteristically dark and band- limited, with their extreme 2kHz-ish high frequency rolloff and maximum 500ms delay time contributing to their restricted yet iconic sound.

Of course, once digital technology came into play in the late ’70s/early ’80s, a cleaner, more full-frequency type of delay effect became the norm. Instead of using mechanical tape or analogue circuitry, the digital delay unit was finally able to loop the input signal in its internal digital memory and spit out mathematically-perfect repeats that never de grade or age over time. As with most ’80s digital audio technology, this cleanliness was seen as a huge benefit over the old haggard delays of years gone by – but now, funnily enough, we all seek those crusty, dusty repeats, with most digital delays emulating the degradation and aging of analogue delay.

Skip forward to today, and the majority of studio delay effects are achieved using software plug-ins. These are often preferred for many reasons – namely instant recall, the ability to load up unlimited instances, the multitude of customisation features on offer, relatively low cost, and more. In-the-box delay tools range from basic DAW-bundled affairs through to all-singing, all-dancing behemoths that pack in every feature under the sun. Many are referred to as ‘multi-tap’ delays, as they contain multiple independent delay lines within one interface.

Filters can have a big impact… a low-passed vocal delay can add analogue-style ambience

Whereas reverb effects use multiple short delay lines to replicate acoustic reflections in a physical space, a delay device stores the input signal in a buffer, then repeats it after an amount of time determined by the Delay Time parameter. The time can be set in milliseconds, or in the case of software plug-ins, set in rhythmic divisions (1/4-note, 1/8-note etc) clocked to your DAW’s tempo. Increase the delay’s feedback amount and the delay’s output is fed back into the input, causing the repeats to increase and intensify to create the classic repeating echo effect. Delay traditionally operates in mono by default, but there’s usually an offset dial for delaying the timing of the repeats between the left and right channels by a few milliseconds – ideal for giving mono sound sources instant, impressive width. Plus, many devices feature a ping-pong mode, whereby each repeat is panned to an alternate side of the stereo field for a bouncing left-to-right effect.

Dry/wet control

With most delay applications, you’ll usually want to hear both the target sound and the delayed signal in the mix. Therefore, if a delay effect is inserted in series over a channel, the dry/wet mix control is used to set the balance between the dry source sound and the repeats. Alternatively, a common studio technique is to use send/return set-ups: by placing the delay effect on a mixer’s aux return channel, then sending various amounts of multiple mix signals to this single delay, you can share processing resources across the different tracks, and even apply extra effects such as filtering or EQ to the delayed signal in isolation.

But when should you place a delay directly on a signal, or when to use send/returns? Well, the latter offers maximum mixing flexibility, as you have a separate channel containing just the delayed signal, making it easier to level and sculpt the delay on its own, using additional processes such as filtering, EQ and more. This also helps if you need to print your multi-track mix to stems, as you’ll capture the delay signal as a separate audio file, giving more possibilities for editing and processing come mix time. Also, fading up the delay on a separate channel keeps the dry signal at 100% volume, whereas using an insert delay effect’s dry/wet mix will turn down the dry signal slightly. However, in the current age of super-fast computers and multiple plug-in counts, it can be more convenient to throw separate delays across different channels and dial in

settings quickly.

Change of tone

Many delays feature onboard low-cut/high-pass and high-cut/ low-pass filters for altering the delayed signal’s tone. This simple process can have a big impact upon the effect you’re going for – for example, a low-passed vocal delay can add dark, aged, analogue-style ambience; and extreme high-pass filtering over the same delay might add subtle treble width and sparkling character to the voice. Some delay processors even feature dedicated EQ controls for shaping the delay’s frequencies further.

The more versatile delay plug-ins are able to model the specific tonal characteristics of analogue tape delays, BBD devices and even specific vintage units. Many plug-ins offer a Repitch mode: when the delay time amount is changed, the virtual tape reel’s speed is altered, causing the pitch of the delays to waver for those classic, tape-style pitchwobbling feedback tails heard in genres such as Dub Reggae.

Many delay plug-ins also offer internal saturation stages for dialling in the exact amount of dirt and drive; while others even allow you to switch between various delay algorithms or modes to emulate specific iconic hardware delay units and pedals such as the Echoplex, Roland Space Echo, and ElectroHarmonix Memory Man. SoundToys’ EchoBoy plug-in allows you to choose from one of 30 styles; and FXpansion’s Bloom authentically replicates the effect of either aged tape, BBD or crunchy digital delay.