Room Modes

{
  "asOf": "2026-10-11T14:38:35.142Z",
  "coincidentModePairs": 140,
  "degraded": false,
  "disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
  "firstAxialHz": {
    "height": 57.202,
    "length": 34.321,
    "width": 42.902
  },
  "heightM": 3,
  "lengthM": 5,
  "lowestModeHz": 34.321,
  "maxHz": 300,
  "modeCountBelowMaxHz": 230,
  "modes": [
    {
      "hz": 34.321,
      "order": "1,0,0",
      "type": "axial"
    },
    {
      "hz": 42.902,
      "order": "0,1,0",
      "type": "axial"
    }
  ],
  "notChecked": [
    "real rooms: non-rectangular shapes, furniture, openings and flexible walls shift and damp modes",
    "rigid-wall assumption (modes in the real room are somewhat lower and wider)",
    "…2 more"
  ],
  "reasons": [
    "Axial modes (one dimension) are the strongest; tangential (two) are about 3 dB weaker, oblique (three) about 6 dB weaker.",
    "140 modes lie within 1 Hz of the previous one (coincident modes build up strongly): rooms with simple dimension ratios do this."
  ],
  "schroederFrequencyHz": 182.574,
  "source": "Rectangular-room normal modes f = c/2 sqrt((p/L)^2 + (q/W)^2 + (r/H)^2) and Schroeder frequency 2000 sqrt(RT60/V), computed locally",
  "speedOfSoundMs": 343.2146,
  "summary": "5 x 4 x 3 m (60 m3), c = 343.21 m/s: lowest mode 34.321 Hz; 230 modes below 300 Hz; Schroeder frequency 182.6 Hz.",
  "verdict": "COMPUTED",
  "volumeM3": 60,
  "widthM": 4
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://audio-calc.x402tookit.com/room-modes?height=3&length=5&rt60=0.5&temperatureC=20&width=4'

# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - 'https://audio-calc.x402tookit.com/room-modes?height=3&length=5&rt60=0.5&temperatureC=20&width=4' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode

// npm i @x402/fetch @x402/evm viem
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

// Pays at most $0.02 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.02" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.02 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Faudio-calc.x402tookit.com%2Froom-modes
const res = await pay("https://audio-calc.x402tookit.com/room-modes?height=3&length=5&rt60=0.5&temperatureC=20&width=4");
console.log(res.status, await res.text());

# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client

# Pays at most $0.02 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.02"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.get("https://audio-calc.x402tookit.com/room-modes?height=3&length=5&rt60=0.5&temperatureC=20&width=4")
    print(res.status_code, res.text)