Digital vs Analogue Guitar Pedals

Let's start by addressing the elephant in the room. Digital vs analogue guitar pedals: which are better?

Well the truth is, neither! Much like cars or guitars, it's not a manufacturer's philosophy that matters, but how they implement it. There are great digital pedals and awful analogue pedals, and vice-versa.

But what are digital pedals and what are analogue pedals?

It all comes down to how the guitar signal is processed. Back in the day, before microchips existed, pedals were built with analogue circuitry: resistors, capacitors and transistors. 

 

Transistors are responsible for providing a pedal's gain, and come in various flavours: BJTs, MOSFETs, JFETs, silicon, germanium and opamps.

Clipping diodes can be used to simulate tube distortion by "clipping" or squaring-off the tops and bottoms of the waveform. They are used in conjunction with a transistor (which produces the waveform to be clipped by the diode) to achieve the distortion effect. 

Resistors and capacitors are responsible for shaping the sound, maybe knocking off some top end or adding a midrange boost.

For more complicated analogue effects such as delays, phasers and choruses, bucket brigade delay (or BBD) integrated circuits are used. Consisting of thousands of transistors, BBDs are responsible for the desirable signal degradation found in so many analogue pedals.

The many different circuit layouts and individual component values can drastically affect the sound of an analogue pedal, and they can also be sensitive to voltage changes, heat and dynamics, so a fading battery, dodgy mains or wet weather can play havoc with stability!

Famous examples of analogue pedals include the Dunlop Fuzz Face, Ibanez TS-808 Tubescreamer, and Dunlop Cry Baby Wah.

Going digital

In the 1980s, mass-produced, affordable microchips changed the landscape forever. Along with the first calculators and home computers, microchips found their way into guitar pedals.

Some of the signature sounds of the era are a result of this change. These early microchips were pretty basic and couldn't manage the high sample rates of modern equivalents, meaning the sampled guitar signal could often be compressed and low fidelity, in the same way a low quality mp3 sounds less realistic and expansive than hi-res lossless audio.

Once the signal is sampled and converted to digital 0s and 1s, effects can then be applied using digital signal processing (DSP). The abilities of early digital pedals were limited due to the processing power required, but as processing power has increased, so has the ability for pedals to apply a multitude of effects at high resolutions.

Today we are spoilt for choice, with multi-fx units able to provide users with a whole rig, and digital effects pedals offering users plenty of tonal options.

This is where the big difference between analogue and digital pedals is felt: whereas analogue pedals are favoured for their imperfections, analogue warmth and amp-like distortion, digital pedals have given guitarists access to unique effects that the analogue realm can't achieve. At its simplest, this means longer delay times in a delay pedal, while at the more complex end of the spectrum it means realistic cab and amp sims that can be loaded from a large database of digitised gear.

Famous digital pedals include the Line 6 Pod, Boss DD-3 Digital Delay and DigiTech Whammy.