Delay

Delay is a simple effect similar to an echo. It simply records and repeats whatever you are playing, delayed by a time setting. Where the "magic" comes in of highly regarded delay units vs. budget units are the extras - these may be additional controls, desirable artifacts left by the delay mechanism (or simulations of them), or the delay's use in combination with other gear, such as other delays or a reverb.

Common Controls

Delay effects typically come with the following controls:

• Time/Rate - Sets how long to wait before replaying the input signal.
• Feedback - The volume at which the delayed signal is fed back into the delay unit. This boils down to how many times you hear your playing audibly repeat. 0% = 1 repeat. 100% = infinite repeats. 50% = many repeats, but 50% as loud for each iteration.
• Mix - The volume of the delayed signal relative to the input signal. For some delays, 100% mix means an equal mix of the input signal and the delayed signal. For others, 100% mix means muting the input signal and only playing the delayed signal.

Additional Features

Tap Tempo

Many delays allow you to tap a switch 2 or more times in order to determine a tempo. Rather than define Time/Rate in terms of ms, it's specified in terms of note duration. For example, rather than say 500 ms, we could say 1 quarter note, which equals 500 ms when playing in 4/4 at 120 bpm.

The advantage of tap tempo is that you can align your delays to occur on the beat, leading to a more coherent-sounding rhythm, without knowing exactly what the tempo will be. This is essential for live situations where there is no click track or other device to make sure everyone is playing exactly at the desired tempo. For instance, if the drummer pushes the beat by just 1 bpm, eventually your delays would be far off the beat. Tap tempo prevents this, allowing you to adjust the delay's timing on the fly.

Modulation

Some delays can apply a chorus-like modulation to the delayed signal, making it more distinguished from the original signal. This can make for a bigger sound, without hurting the clarity of your real-time playing.

Tone

Whether it's implemented as a dampening control, more traditional bass/mids/treble, or even a fully parametric EQ, some delays allow you to adjust the tone of the delayed signal. This also helps distinguish your current playing from your delays. I find I prefer my delays to be darker than my original signal, which makes them sound more like real echoes - the farther the distance sound travels, the more highs it loses. But you can also get some interesting cave or room-like sounds by focusing in the midrange or upper midrange area.

Many tone controls simply apply to the output of the unit, so all your delay trails sound equally dark/bright. Some units incorporate tone-shaping (or it is inherent from the delay mechanism) that really affects the feedback loop vs. the final output. This allows the tone of the delay trails to change over time.

Stereo Delay

Some delays function like 2 delays in one, outputting two different signals, each with their own delay settings. This significantly widens the stereo spectrum, without impacting your real-time playing like some choruses or similar effects would. You can do interesting things like use one really short delay (100-200 ms) to thicken up the sound like a quasi-reverb, while adding the more spacy echo sound on the other side (~600-700 ms).

Some delays only give you a ratio between the stereo delays, rather than independent time controls. This means the delays will sync up and "collide", giving a metallic, ringing sound. For longer delays, this can actually sound quite nice, but for shorter delays it tends to sound a bit weird. To avoid this as much as possible, choose ratios that have high least common multipliers and count how many delays the shorter delay will make before "colliding" with the other delay. For instance, a ratio of 3:5 has a LCM of 15, with 5 delays on the short one before colliding. 3:7 has an LCM of 21, with 7 delays before collision. A 6:7 ratio has an LCM of 42 with 7 delays before collision. These are all pretty good. On the other hand, 1:2 has an LCM of 2 with only 2 delays before collision.

Tape/Bucket Brigade Mode

Most delays are digital units, capable of buffering the input audio without any loss or impact to tone. Earlier analog delay units used tape or bucket brigade technology to create delays, and these had significant impact on tone. Many players associated these units with a certain warmth or vintage quality that was missing in the digital units. Thus, many delays now have switches for analog/tape/bucket brigade operation, simulating the tonal impact these mediums had on the tone.

In addition to simple frequency changes, these could provide certain artifacts like tape crackle or slight distortion. And multi-head tape delays could add some reverb-like "smearing" to the delays, making them a bit softer, allowing them to fill the mix without having too much chaotic direct echoes.

Advice/Tricks

~10-20 ms for a fake doubled guitar sound

600-700 ms for a distinct echo

dampening/darkening tone for a more realistic sound

Changing rate/time with an expression pedal for the chipmunks sound.

Infinite feedback for an intense build-up of sound.