Tempo Calculator Beta

Delays that lock to the groove. Tempo Calculator turns any tempo into delay, reverb and modulation times — in milliseconds, Hz or samples. Type the tempo, tap it, or read it from Pro Tools. Then click a value to copy it into your plugin.

Requires StudioTools 2.4.0 or later. Coming soon to the Mac App Store — beta testers have it now.

What it's for

A delay that repeats on the beat sits in the mix. One that's a few milliseconds off fights it. Many plugins sync to the host tempo — but not all of them, and not every setting does. Hardware units and older plugins want a number.

Tempo Calculator gives you that number. Set the tempo once, and it shows:

• Note values from whole notes to 1/64 notes — straight, dotted and triplet — for delay times, LFO rates, tremolo and auto-pan.
• Reverb times — pre-delay and decay that fit the tempo, so the tail ends before the next note.

It works on its own — no Pro Tools, no DAW needed. With Pro Tools 2025.06 or later, it can also read the tempo straight from your session.

Open it

1. Choose Utilities… in the StudioTools menu.
2. Click Tempo Calculator in the sidebar (the metronome icon).

The summary at the top says it all: Delay, reverb and modulation times for any tempo — type it, tap it or read it from Pro Tools. Click a value to copy it.

Set the tempo

There are three ways to set the tempo. Whichever you use, the line under the Tempo field tells you where the tempo came from — for example Typed, Tapped · 6 taps or From Pro Tools · bar 12 · 6/8 · 48 kHz.

The tempo is always in quarter notes per minute (BPM), from 20 to 400 BPM.

Type it

Type the tempo in the Tempo field. The table follows as you type.

• Decimals work with a point or a comma: 92.5 and 92,5 are the same.
• You can type "bpm" after the number — 120 bpm is fine.
• If the text isn't a tempo, the field says so — Enter a tempo in BPM, for example 120. or Enter a tempo between 20 and 400 BPM. The table keeps the last values, dimmed, until the tempo is valid again.

÷2 and ×2 next to the field halve and double the tempo — handy for half-time and double-time feels. They're disabled when the result would fall outside 20–400 BPM.

Tap it

Don't know the tempo? Tap along. Click the Tap pad on the right in time with the music — or press T or Space.

• The pad has focus when the utility opens, so you can start tapping on the keyboard right away. Typing in the Tempo field never taps.
• The pad shows Click or press T or Space, then counts your taps: 6 taps.
• The tempo is the average of your last 8 taps, rounded to 0.1 BPM. Keep tapping and it settles.
• Pause for more than 2 seconds to start over.
• Missed a beat? A tap that's far off (more than 40 % from the average, after the first 3 taps) restarts the count from the tap before it — so one slip doesn't ruin the result.

Read it from Pro Tools

Working in Pro Tools? Click Read from Pro Tools to take the tempo from the session. StudioTools connects to Pro Tools automatically — see Pro Tools connection.

• Where it reads. At the start of your timeline selection — or at the edit cursor if nothing is selected. The caption under the button reminds you: Uses the tempo at the start of your timeline selection. On a tempo ramp, you get the average tempo over that quarter note.
• Sample rate too. It also sets the sample rate for the Samples column to the session's rate.
• One read, not a live link. The tempo is read once, when you click. If the tempo changes in the session — or you move to a part with a different tempo — click the button again.

The button needs an open session and Pro Tools 2025.06 or later. If something is missing, the button is disabled and a line under it says why: Open a session in Pro Tools to read its tempo. or that reading the tempo needs Pro Tools 2025.06 or later (with the version you're running). Typing and tapping always work.

Note values

The Note values table has a row for each note from 1/1 (a whole note) to 1/64, and three columns:

• Straight — the plain note value.
• Dotted — one and a half times as long. A dotted 1/8 delay is the classic rhythmic echo.
• Triplet — two thirds as long, for shuffles and swung feels.

At 120 BPM, for example:

Units: ms, Hz or Samples

Switch units with ms | Hz | Samples above the table. The caption under the table says which unit you're looking at — for example Values in milliseconds. Click a value to copy it.

With Samples, a sample-rate menu appears: 44.1, 48, 88.2, 96, 176.4 or 192 kHz. Pick your session's rate — or click Read from Pro Tools, which sets it for you.

Copy a value

Click any value to copy it. A message confirms what you copied, for example Copied 500 ms. Then paste it into your plugin.

Only the number is copied — no unit, a point as the decimal separator, no thousands separators and no trailing zeros. So 500, 187.5 or 24000 paste straight into a plugin field.

Reverb

A reverb tail that dies away before the next note keeps the mix clear. The Reverb section gives you a starting point for four sizes:

The values above are for 120 BPM with a 1/64 pre-delay.

• Pre-delay is a note value you choose in the Pre-delay menu: None, 1/128, 1/64 (the default) or 1/32.
• Decay is the note length minus the pre-delay — so pre-delay and decay together end exactly on the next note.
• Total is pre-delay plus decay — the full note length.
• A "bar" is a bar of 4/4.

All values are in milliseconds, and you can click any of them to copy it. As the caption says: A starting point — trust your ears.

Tips and troubleshooting

• It remembers. Tempo Calculator keeps the tempo, the unit, the sample rate and the pre-delay choice for next time.
• Tapping gives a wobbly tempo. Tap at least 8 times — the result is the average of the last 8. If you're way off, pause for 2 seconds and start again.
• Pressing T or Space doesn't tap. The pad needs focus — click it once. Keys typed into the Tempo field never tap.
• Read from Pro Tools is disabled. The line under it says why: open a session in Pro Tools, or update to Pro Tools 2025.06 or later.
• An error starting with Couldn't read the tempo from Pro Tools. Check that Pro Tools is running with the session open, then click the button again.
• The tempo didn't change when the song did. Read from Pro Tools reads once. Select a spot in the new section and click it again.
• The 1/4 row doesn't match the beat in 6/8. Tempos here are per quarter note, but Pro Tools counts eighth notes in x/8 meters. One beat of 6/8 is the 1/8 row.
• Need the Logic Pro tempo? Type it, or tap along — reading the tempo works with Pro Tools only.