# Audio Calc: Sound Wavelength & Speed Calculator

> Audio Calc: Sound Wavelength & Speed Calculator is a paid API for AI agents from audio-calc.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-30).

Calculates speed of sound, wavelength, period, and delay-per-metre for audio frequencies at a given air temperature, with bidirectional frequency/wavelength/delay/distance conversions.

## Facts

- Endpoint: GET https://audio-calc.x402tookit.com/sound-wavelength?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/audio-calc-sound-wavelength-speed-calculator-d99742bb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_jqPeFDzxZbIdYdn2GDGzd

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability audio-calc-sound-wavelength-speed-calculator-d99742bb
```

Example prompt: What's the wavelength and quarter-wavelength of a 1 kHz tone at 20°C, and how long is the delay per metre at that temperature?

## When to prefer this

Choose this endpoint when you need precise acoustic physics calculations — speed of sound at a specific temperature, wavelength/frequency conversions, or delay-to-distance mapping — rather than a general physics formula or table lookup. It is purpose-built for audio engineering contexts and returns all derived quantities (quarter-wave, delay per metre, feet per ms) in a single call, making it ideal for speaker placement, room acoustics, and live sound delay alignment tasks.

## Known failure modes

- Missing all optional query params (frequencyHz, wavelengthM, delayMs, distanceM) may return an error or empty calculation
- Extremely high or low temperatures outside physical plausibility may produce unexpected results
- Conflicting inputs (both frequencyHz and wavelengthM supplied) may cause ambiguity in the response
- HTTP 402 returned if payment is not attached or USDC balance is insufficient

## How this service works

Speed of sound in air at a temperature, wavelength and period for a frequency or the reverse, with delay per metre.

## Output

Returns a JSON object with speedOfSoundMs, wavelengthM, wavelengthCm, halfWavelengthM, quarterWavelengthM, periodMs, delayMs, distanceM, delayPerMetreMs, metresPerMillisecond, feetPerMillisecond, temperatureC, and frequencyHz — covering all computed acoustic properties for the given inputs.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [],
     "properties": {
      "delayMs": {
       "type": "number",
       "description": "A delay in ms to turn into a distance"
      },
      "distanceM": {
       "type": "number",
       "description": "A distance in metres to turn into a delay"
      },
      "frequencyHz": {
       "type": "number",
       "description": "Frequency in Hz (use this, or wavelengthM, or delayMs)"
      },
      "wavelengthM": {
       "type": "number",
       "description": "Wavelength in metres"
      },
      "temperatureC": {
       "type": "number",
       "description": "Air temperature in C (default 20)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "asOf": {
       "type": [
        "null",
        "string"
       ]
      },
      "source": {
       "type": [
        "null",
        "string"
       ]
      },
      "delayMs": {},
      "reasons": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "summary": {
       "type": [
        "null",
        "string"
       ]
      },
      "verdict": {
       "type": [
        "null",
        "string"
       ]
      },
      "degraded": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "periodMs": {
       "type": [
        "null",
        "number"
       ]
      },
      "distanceM": {},
      "disclaimer": {
       "type": [
        "null",
        "string"
       ]
      },
      "notChecked": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "frequencyHz": {
       "type": [
        "null",
        "number"
       ]
      },
      "wavelengthM": {
       "type": [
        "null",
        "number"
       ]
      },
      "temperatureC": {
       "type": [
        "null",
        "number"
       ]
  
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/audio-calc-sound-wavelength-speed-calculator-d99742bb/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from audio-calc.x402tookit.com](https://www.zero.xyz/host/audio-calc.x402tookit.com/llms.txt)