Audio Calc
Loudness maths: gain to a LUFS target or platform, resulting true peak vs ceiling, or combining segment loudness.
MediaLiveeip155:8453Exactvia cdp
AudioLufsLoudnessMastering
Calls · 30d
1
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 4 snapshots so far.
$24.31
Verified settled volume
1,175 settlements proven x402 by their on-chain EIP-3009 marker.
$0.020
Listed price
As published in the catalog. Always read the live 402 before paying.
1
Calls · 30d
Upstream's own call count for this endpoint, not ours.
1
Unique payers · 30d
Last called 2026-10-20 20:58Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0xb531320805C5BED1D46AEaDcF4F008FDF172DBDaThe wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.
Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
Provider
The payTo wallet does not resolve to a registered ERC-8004 agent. That is not a verdict on the service — most of the catalog is unregistered.
Live 402 challenge
Captured by the enrichment pass, not read just now. Prices can change — always read the 402 the endpoint answers with.
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"reasons": [
"Loudness changes dB for dB with gain, so the gain is simply target minus measured.",
"Turning down never raises the peak."
],
"summary": "-9.5 LUFS to -14 LUFS (spotify): -4.5 dB. True peak -0.3 becomes -4.8 dBTP, 3.8 dB under the -1 dBTP ceiling.",
"verdict": "TURN_DOWN",
"degraded": false,
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"disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
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"Turning down never raises the peak."
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"verdict": "TURN_DOWN",
"degraded": false,
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"reasons": [
"Loudness changes dB for dB with gain, so the gain is simply target minus measured.",
"Turning down never raises the peak."
],
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"verdict": "TURN_DOWN",
"degraded": false,
"platform": "spotify",
"disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
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"BS.1770 gating (absolute -70 LUFS and relative -10 LU): combining segments here averages ALL energy ungated, so measure a whole programme with a meter for a delivery value",
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"alsoAvailable": {
"llms": "https://audio-calc.x402tookit.com/llms.txt",
"catalog": "https://audio-calc.x402tookit.com/catalog",
"message": "Audio Calc has 12 pay-per-call endpoints (Audio engineering maths for agents: sample rates, bit depth, bitrates, dB sums, SPL, LUFS, latency, tuning ratios and room modes.), from $0.02 a call. See the full menu and send your agents our way.",
"openapi": "https://audio-calc.x402tookit.com/openapi.json",
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"url": "https://audio-calc.x402tookit.com/sample-rate",
"path": "/sample-rate",
"what": "Nyquist frequency for a sample rate, plus the alias frequency and samples per cycle of a…",
"price": "$0.02"
},
{
"url": "https://audio-calc.x402tookit.com/tuning-temperament",
"path": "/tuning-temperament",
"what": "Frequencies, cents and ratios of the 12 notes in equal, 5-limit just, Pythagorean or quar…",
"price": "$0.02"
},
{
"url": "https://audio-calc.x402tookit.com/bit-depth",
"path": "/bit-depth",
"what": "Dynamic range, levels and smallest step for a PCM bit depth, theoretical SNR, and the bit…",
"price": "$0.02"
}
]
}
}Accepts
The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.
0.02USDC≈ $0.02 USD
on Base · exact scheme
Pay 0.02 USDC on Base to 0xb531…2DBDa. The signed payment is good for 5 minutes.
- Paid to
- 0xb531…2DBDa
- USD Coin contract
- 0x8335…02913
- Payment window
- 5 minutes
- As published
- 20000 smallest units
20000units
on solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp · exact scheme
That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.
- Paid to
- DUPiup…eEm8s
- Token contract
- EPjFWd…TDt1v
- Payment window
- 5 minutes
20000units
on Polygon · exact scheme
That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.
- Paid to
- 0xb531…2DBDa
- Token contract
- 0x3c49…c3359
- Payment window
- 5 minutes
20000units
on Arbitrum · exact scheme
That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.
- Paid to
- 0xb531…2DBDa
- Token contract
- 0xaf88…e5831
- Payment window
- 5 minutes
The catalog’s raw entry
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{
"bazaar": {
"info": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"lufs": -9.5,
"target": "spotify",
"ceilingDbtp": -1,
"truePeakDbtp": -0.3
}
},
"output": {
"type": "json",
"example": {
"asOf": "2026-10-11T14:38:34.877Z",
"mode": "gain",
"gainDb": -4.5,
"source": "ITU-R BS.1770 / EBU R128 loudness arithmetic (level offsets add in dB; energies average linearly); platform targets as commonly published, computed locally",
"reasons": [
"Loudness changes dB for dB with gain, so the gain is simply target minus measured.",
"Turning down never raises the peak."
],
"summary": "-9.5 LUFS to -14 LUFS (spotify): -4.5 dB. True peak -0.3 becomes -4.8 dBTP, 3.8 dB under the -1 dBTP ceiling.",
"verdict": "TURN_DOWN",
"degraded": false,
"platform": "spotify",
"disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
"gainLinear": 0.595662,
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"BS.1770 gating (absolute -70 LUFS and relative -10 LU): combining segments here averages ALL energy ungated, so measure a whole programme with a meter for a delivery value",
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"youtube": -14,
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"ebu-r128": -23,
"apple-music": -16,
"arib-tr-b32": -24,
"amazon-music": -14
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}
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},
"schema": {
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"type",
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"type": "string"
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"queryParams": {
"type": "object",
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"lufs": {
"type": "number",
"description": "Measured integrated loudness in LUFS (negative), for example -9.5"
},
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"type": "string",
"description": "Target LUFS or a name: spotify, youtube, apple-music, amazon-music, tidal, podcast, ebu-r128, atsc-a85, arib-tr-b32"
},
"segments": {
"type": "string",
"description": "To combine: lufs:seconds pairs, for example -20:30,-10:30"
},
"ceilingDbtp": {
"type": "number",
"description": "True-peak ceiling in dBTP (default -1)"
},
"truePeakDbtp": {
"type": "number",
"description": "Measured true peak in dBTP, to predict the peak after the gain"
}
}
}
},
"additionalProperties": false
},
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}
}Provenance
- Seen in the source catalog
- 2026-10-20 20:58Z
- Last indexed by Roundhouse
- 2026-10-22 12:40Z
- Last enriched (probe, favicon, geo)
- 2026-10-20 22:15Z
- x402 version
- 2
- Max timeout
- 300s
- Liveness probe
- HTTP 402
Hand this page to an agent
Copy the prompt and paste it into Claude, an MCP client or your own agent — it will vet this service and call it over the free read API. No key, no account.
GET api.roundhouseai.io/v0/endpoints
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 4 snapshots so far. Verified volume counts only settlements with an on-chain EIP-3009 marker.
Show the promptHide the prompt
Using Roundhouse, look up the x402 service Audio Calc and tell me whether it is worth paying: what a call costs, whether the endpoint answered when last probed, and what its payment record actually shows. curl -s 'https://api.roundhouseai.io/v0/endpoints?q=Audio%20Calc' curl -s 'https://api.roundhouseai.io/v0/merchants/<the payTo wallet returned above>' Then call it: read the price from the live 402 at https://audio-calc.x402tookit.com/lufs-math, never from a cached figure, and pay with an x402 client. The /v0 API needs an API key (`authorization: Bearer rh_live_…`) on everything except /v0/unified* and /v0/endpoints. Either pay over x402 (mint a personal key for $0.01 at GET https://api.roundhouseai.io/v0/test/x402), or ask me for an organization key, which I create at https://roundhouseai.io/dashboard/connections. If you have neither, ask before going further. If you do not have Roundhouse tools or skills installed, read https://roundhouseai.io/skill.md first — it is the whole procedure.