Sonic Identity Principles

Sound design philosophy for a tinnitus app. This is the most sensitive design surface Naluma has — every sound the product makes carries meaning for an audience that is hypervigilant about sound. Every principle traces back to the Brand Personality Spectrum and is informed by the therapeutic evidence documented in treatment research. See Visual Identity Direction for the parallel visual framework and Brand Narrative for the verbal identity.

Why This Matters More Than Usual

For most apps, sonic identity is a finishing layer — notification chimes, button clicks, a branded sound logo. For Naluma, sound is product. The audience has a fundamentally altered relationship with sound: they hear a sound no one else can, their auditory system is in a state of heightened gain, and many are hyperacusis-adjacent (sounds that others find normal register as uncomfortably loud or intrusive).

This means every audio decision — including the decision to produce no audio — is a design choice with therapeutic implications. The standard app sound design playbook does not apply.

The Sound Philosophy

Naluma’s relationship to sound mirrors its relationship to the user’s tinnitus: present but not in front of everything. Sound in the app should behave the way the brand promises tinnitus will eventually behave — as background, as texture, as something that is there but doesn’t govern the experience.

This creates three governing principles:

1. Sound as Texture, Not Event

Traced to: Urgent — Still (60% still), Minimal — Expressive (65% minimal)

App sounds should feel like acoustic texture — part of the environment — rather than discrete audio events that demand attention. The brain of a tinnitus patient is already monitoring for auditory signals it cannot control. Adding more discrete signals (chimes, pings, alerts) increases the monitoring load.

When sound is present, it should arrive gradually and leave gradually. No hard onsets. No abrupt terminations. The sound envelope should be slow-attack, slow-release — the acoustic equivalent of the visual motion principle (settling, not snapping).

2. Below the Mixing Point

Traced to: The TRT therapeutic principle that sound enrichment works only when it sits below the level where it starts to mask tinnitus.

Any sound Naluma produces should default to a level where it enriches the acoustic environment without competing with what the user is already hearing — including their tinnitus. This is both a therapeutic principle and a brand principle: Naluma does not overpower. It accompanies.

Practically: default volumes should be low. Volume controls should be prominent and granular. The app should never auto-play sound at a level that surprises.

3. The User Controls the Acoustic Environment

Traced to: Directive — Companion (65% companion), Institutional — Personal (70% personal)

Sound is the one domain where user control is non-negotiable. A tinnitus patient’s relationship with sound is already defined by a loss of control — they hear something they cannot turn off. Naluma must never add to that experience. Every sound the app produces must be:

Optional (can be turned off entirely)
Adjustable (volume, and where possible, character)
Predictable (the user always knows what will happen before it happens)

No surprise sounds. No auto-playing audio on first launch. No sounds that play without explicit user initiation or clear prior consent.

Sound Categories

Notification and Alert Sounds

Recommendation: Minimal to absent.

Push notifications should be silent by default. If the user opts into notification sounds, they should be:

Extremely soft onset (fade in over 200ms+, never a sharp attack)
Low-to-mid frequency range (below 2kHz — away from the 3—6kHz range where most tinnitus sits)
Broadband or noise-based rather than tonal (a tonal notification risks matching someone’s tinnitus frequency, which is both triggering and confusing)
Brief (under 1 second of perceptible sound)
Rounded phonaesthetic character — consistent with the sonorant, open-vowel character established in the brand naming

What to avoid: High-pitched chimes, bell-like tones, anything with energy concentrated in the 3—8kHz range, any sound with a sharp attack transient.

Session Audio (Guided Content)

The therapeutic core. This includes guided sessions, psychoeducation audio, CBT exercises, and any narrated content.

Voice direction:

Warm, mid-range, unhurried. The voice should feel like the Authoritative — Peer position (60% authoritative): knowledgeable and steady, not performatively soothing.
Avoid the “meditation app voice” — the breathy, slow, ASMR-adjacent delivery that the target audience associates with products that didn’t understand their experience. The voice should sound like a real person speaking with care, not a voice actor performing calm.
Pacing should be conversational but with generous pauses. Not slow-motion; not rushed. The pace of someone explaining something important to someone who needs to hear it.

Background audio in sessions:

Broadband, nature-based where appropriate (water, rain, wind through foliage). These are the TRT-validated sound enrichment media with documented ANS relaxation effects and low attentional binding.
Always below the voice. Always optional. Always adjustable independently of voice volume.
No looping patterns short enough to become consciously perceptible as loops. Loop points (if any) should be at least 60 seconds apart and crossfaded.

Ambient / Sound Enrichment

If Naluma offers a sound enrichment tool (distinct from session audio), the principles are:

Broadband > narrowband. Broadband sounds (rain, pink noise, ocean) work regardless of whether the user’s tinnitus is high-frequency tonal, low-frequency hum, or broadband. Narrowband tones risk matching and amplifying specific tinnitus frequencies.
Nature sounds as the primary palette. Therapeutically validated (Jastreboff & Hazell), low attentional binding, measurable ANS effect. Water-based sounds (rain, stream, ocean) are the strongest candidates.
User-adjustable frequency shaping is a differentiator. If the app offers EQ or frequency-band control, it enables users to shape the enrichment around their specific tinnitus frequency — which is a more sophisticated approach than the flat sound libraries offered by masking apps.
Never positioned as masking. The framing must be “enrichment” or “acoustic texture,” not “masking” or “blocking.” Full masking prevents habituation. This distinction is both therapeutic and brand-critical: Naluma does not suppress the sound. It changes the acoustic context in which the sound sits.

The anti-masking-trap principle: Enrichment audio should not create a perceptual rebound when it stops. This means avoiding narrow-band tones and ensuring that sound offset is gradual (long fade-out, not an abrupt stop).

UI Feedback Sounds (Micro-interactions)

Recommendation: Absent by default, optional.

Button taps, toggles, navigation transitions — these should be silent by default. The user is already in an environment where their brain is monitoring for auditory signals. Adding micro-interaction sounds increases the perceptual load without adding information.

If offered as an option for users who want tactile-audio feedback:

Haptic feedback (vibration) preferred over audio
If audio, use extremely subtle broadband sounds (soft “thud” rather than “click”) at very low volume
Never tonal — no pitched sounds for UI interactions

Silence as a Design Choice

Silence is not the absence of design — it is the most deliberate sonic choice Naluma can make.

However: prolonged silence in-app should be handled carefully. The TRT research is clear that silence amplifies tinnitus perception (auditory gain increases to compensate for reduced environmental sound). The app should never create an experience where the user sits in silence staring at a screen — this is the acoustic equivalent of a loading spinner, but worse.

If a screen has no audio content, the app should not imply that audio is about to start (no loading indicators, no “preparing your session” text with no sound). Expectation of sound followed by silence is the worst acoustic UX for this audience.

Brand Sound Logo

The question of whether Naluma should have a sound logo (a short audio signature, like Netflix’s “ta-dum”) deserves specific consideration.

Arguments for: Brand recognition, emotional anchoring, the name Naluma is phonaesthetically rich (nada = sound, luma = light/settling) and could translate beautifully into an audio signature.

Arguments against: Any discrete, recognisable sound that plays repeatedly risks becoming a new auditory fixation for users whose brains are already hyper-monitoring for sound. The sound logo would need to play at app launch or session start — both moments when the user’s auditory attention is already primed.

Recommendation: If a sound logo is developed, it should be:

Extremely soft, broadband, and short (under 2 seconds)
More of a texture shift than a sound event — the acoustic equivalent of a room changing character rather than a bell ringing
Skippable and disableable from first encounter
Tested specifically with tinnitus patients for adverse response before deployment

Alternatively, consider a visual-only brand signature (an animation, a light transition) that represents the brand’s relationship with sound without producing actual sound. This might be the stronger choice: the brand that understands sound so deeply that its signature is visual.

Frequency Safety Guidelines

These are not absolute rules but strong defaults based on tinnitus audiology:

Frequency Range	Guidance	Rationale
Below 250 Hz	Generally safe	Below most tinnitus presentations; felt as much as heard
250 Hz — 2 kHz	Safe zone for brand/UI audio	Below the most common tinnitus range; perceptible but not in the danger zone
2 kHz — 4 kHz	Caution	Overlaps with some tinnitus presentations; use only in broadband context
4 kHz — 8 kHz	High caution	The most common tinnitus frequency range; avoid concentrated energy here in any discrete sound
Above 8 kHz	Avoid in discrete sounds	High-frequency tinnitus range; acceptable only as part of broadband enrichment

Important caveat: Tinnitus frequency varies enormously between individuals. These guidelines reduce risk for the majority but cannot eliminate it for all users. User-adjustable frequency controls remain the most robust solution.

Anti-Patterns

Sounds and patterns that should never appear in Naluma:

Sharp attack transients (clicks, pops, snaps) — trigger the acoustic startle reflex, which is heightened in tinnitus patients
Narrow-band tones in the 3—8 kHz range — likely to match common tinnitus frequencies
Looping patterns with short cycle times (< 30 seconds) — become consciously perceptible and can create attentional fixation
Sudden silence after sound — creates perceptual rebound (tinnitus appears louder by contrast)
Auto-play at unpredictable volumes — loss of acoustic control is the defining experience of tinnitus; the app must never replicate it
ASMR-style whisper content — high sibilance content (S, SH sounds) has energy concentrated in the 4—8 kHz range, exactly where most tinnitus sits
Binaural beats without disclosure — some users report these worsen tinnitus; never auto-play, always opt-in with clear explanation