The Wonders Of The Delay Pedal

These are my delay pedals and I’m going to make them sing for you this evening.

Delay is one of the most common effects in the arsenal of many modern guitarists.  The idea is simple:  it takes the dry input signal, makes copies of the signal, delays them in time, and puts the quieter copies on top of the original.  The result is a sort of echo that gives the signal a nice body and depth.  Although it’s so simple conceptually, the potential sounds any delay can make with the twist of a knob or two are nearly endless.  Though there’s an almost overwhelmingly diverse selection of delay pedals to choose from in any music store  or online boutique, they’re all controlled pretty much the same way.  There are three knobs or some variation thereof on every delay pedal:

1. Output/Mix/Volume: This controls how loud the echos come out of the output.  Tweaking this knob allows you to dial in everything from a subtle reverberation echo to making it sound like there’s another player copying your notes as you play them.
   
2. Delay Time: This controls how quick the pedal pumps out echos.  Tuning this down gives a slap-back effect and pushing it all the way up makes it echo like you’re playing straight into the grand canyon.
3. Feedback/Regen(eration): This controls how loud the individual echos are as they’re fed back into themselves.  It’s loosely “how many” echos you hear every time you play a single note and how loud the echos are in relation to each other.  At the lowest setting, this gives one echo and makes the others almost entirely inaudible.  How it behaves at the highest setting depends heavily on the specific pedal, but I’ll get to that later.

The above controls are described pretty intuitively by this neat block diagram courtesy of Wikipedia:

 There are two kinds of delay on the market today:  analog and digital and while each has their own particular sound and operational characteristics, the differences are subtle and they serve essentially the same purpose.

Analog:

Aptly named, the analog delay is made of exclusively analog components.  Analog components in audio devices are characteristically warmer and more natural sounding since they essentially let the original signal pass through without effecting its quality.  This is as opposed to digital components, which take the signal, sample it, assign discrete values to the samples and then process the signal as a series of samples.  This makes the signal seem pretty much the same, but if you squint really hard, you can see the signal gets all jagged and blocky after all the processing.  Digital devices often sound more “sterile” than analog but often also produce cleaner outputs with less noise.  In addition, there are many things that digital components can do that analog can’t, so many digital effects have a wider range of potential applications.  Despite all of this, many players and nerds such as myself swear by analog even in this modern age of digital everything.  Many in the gear world agree that the pinnacle of modern analog delay technology delay is the MXR Carbon Copy, pictured on the left of the photo at the beginning of this post.  If you crack it open and analyze its insides, it will look something like this:

Click if you’re interested. Don’t worry if you aren’t.

Simple, isn’t it?  Even if this is nothing to you but a mass of scary looking lines and blocks, how it looks isn’t important.  How it sounds is much more interesting:

That is how a typical delay pedal sounds with mix at 12:00 and the regen and delay around 10:30 (knobs on pedals are often described as if they were hands on a clock, most knobs range from 7:00 on the low end to 5:00 when cranked all the way).  This echo is nothing fancy, but it adds a significant amount of presence to the signal.  It draws attention to itself in the mix and can give the illusion of sounding louder when the signal is at the same volume.  You can easily dial in a funky slap-back echo by turning the regen down to 7:00 and the delay down to about 9:00:

The slap-back makes an interesting out of phase sound, like your notes are hitting a puddle and splashing water up at you.  You can even harmonize with yourself by setting regen to 12:00, the delay to 10:00, and pushing the mix to 3:00:

This final feature is what sold me on this particular pedal:  you can make it explode.  No, really.  Listen:

Figuratively, of course.  This monstrosity was made by pushing the regen all the way up and turning the delay time all the way down.  This is unique to analog delays due to how their feedback controls can be designed.  When the regen knob is perfectly set to 12:00, the echos are made to be exactly as loud as the signal that made them was.  This leaves a whole half of the knobs range usually unexplored.  With regen past 12:00 noon, you actually get a positive feedback loop with this pedal.  This just means that the echos are actually louder than the input signal itself, and each subsequent echo is louder than the last since it keeps feeding boosted signals back into itself.  Positive feedback is the same concept behind the ear piercing squeal you get if you hold a microphone too close to the speaker that it’s playing out of.  If done improperly, an effect like this can be dangerous to both equipment and ears, but I have years of experience making strange noises with electronics.  In the recording, I can be heard playing with the regen and delay knobs to control this beast.  Decreasing the regen brings the feedback loop back to reality and stops the vicious cycle while increasing the delay time makes it so that fewer repeats per second fly through the feedback loop, all of which allows me to control how wild the signal gets.  There’s also a cool pitch bending effect to the echos as I move the delay knob back and forth.

Digital:

As described above, the Boss PS2 Digital Pitch Shifter/Delay works on the same principle but in a different way.  Note that even though it does have pitch shifting capabilities, I am using only the digital delay part of this pedal in the recordings:

The differences are subtle, but noticeable to those with discerning ears.  The echos sound more “perfect”, but at the same time also sound thinner and less warm the the analog delay.  One of the big advantages of digital delay though, is that there is a much wider range of possible delay times.  Here’s the digital delay at it’s longest delay time setting:

Things really start to get interesting with you play with the two of them together:

The beginning is a side to side comparison of the analog and digital delays.  The first delay you hear is the analog which is fed into the digital delay.  When each plays individually, it’s pretty easy to hear the differences in quality.  The delay times are set so that the digital delay is repeating at a quarter note pulse and while the analog echos at a quarter note triplet pulse to the digital delay.  This creates a cool rhythmic pattern by playing a single note and adds an interesting set of layers to the passage.

Delay is definitely one of favorite effects as it imparts so much atmosphere and depth to the sound.  Though analog and digital both have their respective uses in different situations, I almost always prefer analog when I’m not using both together.  The natural warmth of analog cannot be beat by the cold, lifeless sound of digital to me.  I’ve always found having a deeper understanding of the inner workings of the equipment I’m using opens up a lot of possibilities for using these devices creatively and effectively and I hope I’ve granted some deeper insight into the wonderful world of delay here this evening.

The Gear Nerd