A
A
Audible
A modulated signal in the human-audible range (roughly 1.5 to 2.5 kHz). The highest throughput of the three modes. Best for quiet environments.
+ Highest throughput- Audible to anyone nearby
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Acoustic
Data over sound
Two devices, one room, no network required.
Channel modes
B
B
Resilient
A lower-frequency signal with enhanced forward error correction. Designed for noisy places including traffic, background conversation and general ambient noise.
+ Noise-tolerant- Reduced throughput
C
C
Ultrasonic
A signal above the human hearing range (roughly 18 to 20 kHz). Nobody in the room can hear it. Throughput is equivalent to the audible mode.
+ Inaudible to humans- Speaker variation may reduce effective range
Strong points
- Effective from close range up to about eight metres under normal indoor conditions.
- Eight selectable tiers across three mode families: audible, resilient and ultrasonic. Each tier balances throughput, noise tolerance and audibility for a specific environment.
- Automatically falls back to a more resilient tier when ambient noise is high.
Trade-offs
- Both devices need to be within hearing range of each other.
- Throughput is approximately 20 to 100 bytes per second depending on the mode. Not suitable for video or large files.
Acoustic channel modes
Measured performance parameters for each acoustic channel mode.
| Tier | Type | Throughput | Effective range | Audible? | Recommended for |
|---|---|---|---|---|---|
| Voice-call resilient | Audible | Under 1 byte per second | Up to 8 m | Yes | Transmission through an active phone call or extreme acoustic interference |
| Voice-call standard | Audible | Approximately 2 bytes per second | Up to 8 m | Yes | Transmission through a phone call with moderate quality |
| Audible rugged | Audible | Under 1 byte per second | Up to 8 m | Yes | Extremely difficult acoustic environments where reliability matters more than speed |
| Audible long-range | Audible | Approximately 1 byte per second | Up to 8 m | Yes | Larger rooms where maximum range is needed |
| Audible balanced | Audible | Approximately 5 bytes per second | Up to 6 m | Yes | Standard indoor transfers |
| Audible quick | Audible | Approximately 15 bytes per second | Up to 4 m | Yes | Quiet environments where higher throughput is needed |
| Ultrasonic long-range | Ultrasonic | Approximately 1 byte per second | Up to 4 m | No | Silent environments requiring maximum range |
| Ultrasonic balanced | Ultrasonic | Approximately 5 bytes per second | Up to 3 m | No | Standard silent transfers: offices, libraries, secure meetings |
Values measured using standard mobile device speakers and microphones at one metre under indoor conditions. Real-world performance ranges from 50 to 100 per cent of these values depending on the acoustic environment.
Get started
Two devices. One shared password. No intermediary.
Install Taftan on both devices, agree on the password through a separate channel beforehand, and run a quick test transfer using whichever channel fits your situation.