# Music Production Calc – Feedback Delay Tail Calculator

> Music Production Calc – Feedback Delay Tail Calculator is a paid API for AI agents from music-production-calc.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-29).

Calculates dB lost per repeat, number of repeats to fall a target dB, and total tail time in milliseconds from a delay time and feedback percentage.

## Facts

- Endpoint: GET https://music-production-calc.x402tookit.com/delay-tail?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/music-production-calc-feedback-delay-tail-calculator-c7eff06d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_McdQ-Qq3I8v04LyKG1jgG

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 music-production-calc-feedback-delay-tail-calculator-c7eff06d
```

Example prompt: What's the total tail time and dB lost per repeat for a delay set to 250ms with 70% feedback, decaying down 60 dB?

## When to prefer this

Use this endpoint when you need precise mathematical computation of delay echo decay characteristics — specifically dB-per-repeat attenuation, number of audible repeats, and total tail duration in ms/seconds — given a delay time and feedback percentage. Ideal for music producers, audio engineers, and DAW automation agents that need to programmatically reason about delay effect parameters without opening a DAW or plugin.

## Known failure modes

- Missing required delayMs or feedbackPercent query parameters returns an error
- feedbackPercent of 0 or 100 (or outside 0–100 range) is invalid and will be rejected
- Very high feedback values (e.g. 99%) yield extremely long tail times and many repeats — response may include a disclaimer
- Negative or zero delayMs is invalid and will be rejected

## How this service works

Feedback delay decay: dB lost per repeat, repeats to fall 60 dB and total tail time in ms from delay and feedback.

## Output

Returns the dB lost per repeat, the number of repeats required to reach the decay target (default 60 dB), the total tail time in both milliseconds and seconds, the feedback ratio, and a table of the first several repeat levels with their time offsets in ms and level in dB. Also includes a summary string and optional disclaimer or degraded-mode flags.

## 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": [
      "delayMs",
      "feedbackPercent"
     ],
     "properties": {
      "decayDb": {
       "type": "number",
       "description": "How far the tail must fall to count as finished, in dB (default 60)"
      },
      "delayMs": {
       "type": "number",
       "description": "Delay time in milliseconds"
      },
      "feedbackPercent": {
       "type": "number",
       "description": "Feedback as a percent of the previous repeat, above 0 and below 100"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "asOf": {
       "type": [
        "null",
        "string"
       ]
      },
      "source": {
       "type": [
        "null",
        "string"
       ]
      },
      "tailMs": {
       "type": [
        "null",
        "number"
       ]
      },
      "delayMs": {
       "type": [
        "null",
        "number"
       ]
      },
      "reasons": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "summary": {
       "type": [
        "null",
        "string"
       ]
      },
      "verdict": {
       "type": [
        "null",
        "string"
       ]
      },
      "degraded": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "disclaimer": {
       "type": [
        "null",
        "string"
       ]
      },
      "notChecked": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "dbPerRepeat": {
       "type": [
        "null",
        "number"
       ]
      },
      "tailSeconds": {
       "type": [
        "null",
        "number"
       ]
      },
      "decayTargetDb": {
       "type": [
        "null",
        "number"
       ]
      },
      "feedbackRatio": {
       "type": [
        "null",
        "number"
       ]
      },
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/music-production-calc-feedback-delay-tail-calculator-c7eff06d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from music-production-calc.x402tookit.com](https://www.zero.xyz/host/music-production-calc.x402tookit.com/llms.txt)