Delay delay delay delay - ANALOG or DIGITAL?
So, what is delay?
Delay is an often used but heavily misunderstood pedal. For starters, if you have a lot of pedals going at once you may end up with a really muddy sounding signal if you're adding that output to a live band setting (see the Wampler video about getting a better tone within a mix). You can also add more depth to your signal, if you aren't playing in a mix and want your sound to feel wide and deep.
The main benefit of a digi delay over analog is tap tempo - otherwise, keeping your signal analog means you're adding warmth to your signal instead of losing anything. This isn't as theoretical as it sounds - watch this video to get an idea.
Analog delay pedals usually rely on a bucket-brigade device (BBD) chip that sends the analog signal through a series of capacitors, one step per clock cycle. The repeats of analog delays tend to get a bit warmer and darker and a bit more diffuse (broken up) with each step, which imparts a very particular sonic signature. Due to the limitation of BBD chips, analog delay pedals tend to offer shorter maximum delay times than digital delays.
Analog or Digital?
Digital delay pedals use digital signal processing (DSP) chips to create their echo effects. This means that they can be as colored or transparent, or long or short, as the designers choose to make them. They offer more flexibility than analog delay pedals, some even offering MIDI control. However, your guitar signal must be converted to digital at the front end of the pedal, and then back to analog at the output, and not all digital delay pedals have had the best A/D and D/A converters. These days, however, modern pedals offer 24-bit resolution and quality conversion.