Tension Support: Tapping, Readings and Accuracy

How to tap for a clean reading

Lay the drum on a rug, a pillow or your lap, so the other head cannot ring. Turn the snares off.
Put the phone on the floor or a chair 30 to 60 cm from the drum. On iPad the microphones are on the top edge; point that edge at the drum.
Tap lightly with the tip of a stick about an inch (2.5 cm) in from the rim, right next to a lug. For the fundamental (Center mode), tap in the middle of the head.
Resting a finger lightly in the middle of the head makes lug readings cleaner.

What the messages mean

MessageWhat to do

Tap a little lighter: the pitch was still fallingA hard hit raises the pitch for a moment. Tap softer; Tension reports the pitch once it settles.

Tap again: that sounded like an overtoneAnother ringing pattern was about as strong as the lug pitch. Tap a little closer to the rim, lighter.

Too quiet: tap a little harderMove the phone closer or tap a bit harder.

Too loud: tap lighter or move the phone backThe microphone clipped. Move the phone back.

Too noisyBackground noise covered the tap. Find a quieter moment.

Lug 3 is far from the other lugsThe reading stays on the ring. If it surprises you, tap that lug again.

AirPods or a headset connected

Tension needs the phone's own microphone. If AirPods or a headset take the input, it shows a warning with a Use iPhone microphone button.

How accurate is it?

We do not own a drum set, so we tested the measuring engine three ways and publish all of it, including what did not pass.

TestResult

3,740 simulated taps with rooms, background noise (white, pink, talking, a fan), snare wires, a previous lug still ringing and a phone microphone that loses bassWith the tap at least 10 dB above the noise: 97% of the numbers shown were within 0.3 Hz or 3 cents of the true pitch (95% of them within 0.19 Hz). In the noisiest band we tested (10 to 15 dB) it was 93% for lug taps. 0.4% picked the wrong mode or octave. 86% of taps gave a number; the rest said Tap again.

Same drums without room reverb99.4% within 0.3 Hz or 3 cents.

10 taps on the same lugTypical spread under 0.01 Hz; worst of 32 drums 0.09 Hz.

Two lugs 2 Hz apart155 of 155 pairs in the right order when both taps gave a number.

Background noise only, no drum0 numbers from 148 noise bursts.

Physical model of a drum head with uneven tension (finite differences, 90 cases)Every reading fell inside the true pair of lug-pitch frequencies. Beating was found in 9 of 9 cases where it can be heard in one ring (split of 1 Hz or more), and never reported falsely.

77 public recordings of real toms, snares, kicks, rototoms and timpani (CC0 / CC-BY)Every number shown matched a real frequency of the drum found by two separate spectrum tools. It showed a number for 31 of 77 recordings: hard hits whose pitch was still falling and most timpani hits got Tap again.

What we could not test: a real drum in front of a real iPhone. Results depend on the room and how you tap. Very small differences between lugs (for example one lug 3% tighter) make a beat too slow to hear in one tap, so a clean result means close, not perfect. Low drum mode is in beta. Timpani are not supported well yet.

Restore your purchase

Pro is tied to your Apple Account. On a new iPhone or iPad open Settings in Tension and tap Restore Purchases, signed in with the same Apple Account. Family Sharing is on. If Pro is refunded, you can still measure everything; only the Pro extras close.

Where are my readings?

On screen for the current session only. Tension saves no drums, no history and no recordings. Use Share on the Summary tab to keep a copy in Notes, Files or a message.