Why does the panel tell me how many repeats fit?

Because a delay only produces as many repeats as the file has room for. A five hundred millisecond delay on a three second file gives five repeats at most, and everything after that falls past the end. Knowing the count is the quick way to see whether the effect will be heard as an echo pattern or as a single tap.

What does the summed tap energy figure mean?

It is the total of the repeats' amplitudes, which for a constant feedback is a geometric series. At a hundred percent echo level and high feedback the total grows quickly, which is the arithmetic reason a heavily fed delay can build up to something much louder than the dry signal.

How do I get a rhythmic echo rather than a wash?

Choose a delay time that is a note division of the tempo, keep the feedback moderate so the repeats are countable, and keep the echo level below the dry sound. A dotted eighth at a moderate feedback is the classic setting for a wide, rhythmic repeat.

Why is feedback capped?

Because at a hundred percent the loop would never decay, and above it the recursion would grow without limit and the output would run away into noise. The cap keeps the effect inside the range where it behaves predictably.

Can I make the repeats darker than the original?

Not with this tool, since each repeat is a copy of the dry signal at a reduced level. To soften them, apply a gentle equaliser or the old tape effect to the whole result, which colours the repeats and the dry sound together.

Echo / Delay Generator

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Echo Delay Generator repeats a sound at a chosen interval, with feedback setting how many repeats follow. It is the simplest way to add depth or a rhythmic echo to a recording.

What is Echo / Delay Generator?

Set the delay time, the feedback and the echo level, drop a file, and process; the panel reports how many repeats fell inside the file.

The controls:

A delay time from twenty to twelve hundred milliseconds in five millisecond steps, defaulting to two hundred and fifty.
Four presets naming the usual musical settings: a slapback at eighty milliseconds, an eighth note at two hundred and fifty, a dotted eighth at three hundred and seventy five, and a quarter note at five hundred.
A feedback control from nothing to ninety five percent in five percent steps, defaulting to thirty five.
An echo level from nothing to everything, defaulting to forty percent, which sets how loud the echoes are against the dry sound.

The arithmetic is short enough to write out. Each output sample is the dry sample plus the echo level multiplied by the echo signal at that point, and the echo signal is the dry sample from one delay earlier plus the feedback multiplied by the echo from one delay earlier. That recursion produces a tap at every whole multiple of the delay time, with amplitudes that fall by the feedback factor each time, so a feedback of thirty five percent gives repeats at the set level, then thirty five percent of that, then thirty five percent of that again. The panel reports how many of those taps actually fall inside the file, counted as the largest whole multiple of the delay that fits, and it also gives the summed tap energy: a geometric series which is the honest measure of how much echo has accumulated at any moment. That count is worth looking at, because a long delay on a short file produces one or two repeats at most, and the tail beyond the end is simply dropped rather than appended as it is with a reverb. The presets exist because the delay time is usually chosen against a tempo rather than by ear, and the four named settings cover the intervals that come up most often. Feedback above about ninety percent starts to sound less like echo and more like a sustained tone, since the repeats stop decaying at a rate the ear can follow.

Where it is limited:

No tempo detection, so the musical presets assume the usual hundred and twenty.
Repeats past the end of the file are dropped rather than appended.
No ping-pong routing between the channels.
No filtering of the repeats, so each one is as bright as the dry sound.
Feedback is capped below the point where the recursion could run away.
Output is sixteen bit WAV.

Use it to put a slapback behind a vocal, to add rhythmic depth to a guitar, or to make a single hit feel like a pattern. When the repeats should be worked out against a tempo rather than guessed at, the delay time calculator gives the note divisions, and when the repeats should be smeared into a space instead of staying distinct, the reverb simulator is the tool for that.

How to use Echo / Delay Generator

Drop an audio file onto the panel.
Set the delay time, using a preset if you want a musical interval.
Choose the feedback for how many repeats should follow and the echo level for how loud they are.
Press process and check the reported number of repeats that fit inside the file.

When to use Echo / Delay Generator vs related tools

Echo Delay Generator is the tool for discrete repeats, which is what makes it rhythmically useful. Reverb Simulator and Convolution Reverb smear the repeats into a space instead. When the delay time has to be a note division rather than a guess, Delay Time Calculator supplies it, and Chorus Effect uses much shorter delays to thicken a sound rather than to repeat it.

Privacy & Security

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