Step 6 · Audio

This step sets up the therapeutic sounds and the rules that match the right sound to each participant. It has several parts, worked through in order.

The building blocks

Hearing profiles

The presets that describe a participant’s hearing (for example None, Mild, Moderate, Severe). A participant is matched to one of these.

Stimulus types

The kinds of stimulus used in tinnitus matching.

Modulation bands

The frequency bands a sound can be modulated in (for example 2–4 kHz).

Frequency mapping

The table that maps a participant’s matched tinnitus frequency to the modulation band they should receive, with separate active and placebo columns so sham arms get the control band.

Uploading the sounds

Two kinds of audio are uploaded:

• Matching audio: used during tinnitus matching.

• Therapeutic sounds: what participants listen to during the trial.

Each therapeutic sound is identified by three things: its sound type, the hearing profile it is for, and its modulation band. Files are recognised by name using the convention:

{SoundType}_{HearingProfile}_{ModBand}

for example Amp_Mild_2-4. Unmodulated sounds (used by washout (unmodulated) arms) have no band.

The step shows a coverage summary per sound type, how many of the expected hearing-profile × modulation-band combinations you have uploaded, so you can see at a glance what is still missing.

How a sound is chosen for a participant

When a participant is ready to listen, the portal selects their sound from the sound type of their current arm, their confirmed hearing profile, and the modulation band their matched tinnitus frequency maps to (active or placebo, depending on the arm). The full matching logic is described in Audio pipeline in depth.

Next: Step 7 · Compliance.