{ "title": "Audio equalizer", "human_url": "https://happytails.ai/en/media-tools/audio-equalizer/", "agent_url": "https://happytails.ai/agents/en/media-tools/audio-equalizer/", "language": "en", "markdown_url": "https://happytails.ai/en/media-tools/audio-equalizer.md", "content": "Audio equalizer\nShape the tone of a recording with up to 10 filter bands, see the combined response curve and compare the result at matched loudness.\nHow to use Audio equalizer\nChoose the recording.\nWrite one band per line: the filter type, the frequency in Hz, the gain in dB and the Q.\nApply the bands and inspect the response curve.\nCompare the original and processed sound with loudness matching, then download the WAV.\nHow can we improve this tool?\nReport a problem or share an idea.\nPlease leave out private information. Your message and the tool name go to our team via PostHog.\nUseful next steps\nAudio hum filter\nAudio de-esser\nRemove background noise\nOne recording up to 256 MiB and 10 minutes, up to 10 bands written in at most 10,000 characters. WAV is read with every sample intact; other formats are decoded by your browser at 48 kHz. Everything is processed on your device and nothing is uploaded. Download: WAV in the source format or the format you choose, a JSON report and a CSV response curve.\nBand format\nEach line is type, frequency, gain and Q, for example peak 1000 -3 1.4. Types are peak, lowshelf, highshelf, highpass, lowpass, bandpass and notch. Gain is ignored by pass and notch filters. Q defaults to 0.707 and gain to 0. Lines starting with # are ignored.\nFilters\nEach band is a second-order filter from the RBJ Audio EQ Cookbook by Robert Bristow-Johnson, applied in order. Settings that would make a filter unstable, or a frequency at or above half the sample rate, are rejected. Gains run from -48 to 48 dB and Q from 0.05 to 100.\nComparing fairly\nBoosting makes a sound louder, which can make it seem better. Use loudness matching in the player for a fairer comparison. It attenuates the louder version during playback and leaves your download unchanged. The chart shows the combined filter response; the full table and CSV contain all 120 measured frequencies.", "content_format": "text/plain", "visibility": "public", "links": [ { "name": "Audio hum filter", "url": "https://happytails.ai/en/media-tools/audio-hum-filter/" }, { "name": "Audio de-esser", "url": "https://happytails.ai/en/media-tools/audio-de-esser/" }, { "name": "Remove background noise", "url": "https://happytails.ai/en/media-tools/remove-background-noise/" } ], "tool": { "id": "audio-equalizer", "category": "media-tools", "built": true, "requirements": "One recording up to 256 MiB and 10 minutes, up to 10 bands written in at most 10,000 characters. WAV is read with every sample intact; other formats are decoded by your browser at 48 kHz. Everything is processed on your device and nothing is uploaded. Download: WAV in the source format or the format you choose, a JSON report and a CSV response curve.", "implementation": { "fields": [ { "key": "encoding", "label": "WAV sample format", "value": "match", "type": "select", "values": [ "match", "pcm16", "pcm24", "float32" ], "labels": { "match": "Same as source", "pcm16": "16-bit PCM", "pcm24": "24-bit PCM", "float32": "32-bit float" } } ], "registrationFamily": "audio-dsp-dynamics-filters", "presentation": "metrics", "files": true, "accept": ".wav,.mp3,.m4a,.aac,.flac,.ogg,.oga,.opus,.webm,audio/*", "maxFileBytes": 268435456, "inputMaxLength": 10000, "inputErrorCode": "AUDIO_DSP_DYNAMICS_FILTERS_TOO_LONG_BANDS", "note": "Runs locally in your browser. Applies up to 10 bands to one recording up to 10 minutes.", "experience": { "automatic": false, "single": false, "inputMaxLength": 10000, "inputMode": "text", "label": "Equalizer bands", "placeholder": "peak 1000 -3 1.4", "help": "One band per line: type, frequency in Hz, gain in dB and Q. Up to 10,000 characters. Review the settings before running.", "helpParts": [ "One band per line: type, frequency in Hz, gain in dB and Q.", "Up to 10,000 characters.", "Review the settings before running." ], "action": null }, "mode": "explicit", "interactive": false }, "execution": "Browser interface", "api": null, "browser_agent": { "supported": true, "name": "run_current_tool", "discovery": "WebMCP on the human page in a supporting browser", "verification": "See audit/API-AUDIT.md; availability is not verification" } }, "markdown": "# Audio equalizer\n\n- Human page: https://happytails.ai/en/media-tools/audio-equalizer/\n- Markdown: https://happytails.ai/en/media-tools/audio-equalizer.md\n- Structured JSON: https://happytails.ai/agents/en/media-tools/audio-equalizer/index.json\n- Visibility: public\n\n## Tool capabilities\n\n| Property | Value |\n| --- | --- |\n| Tool ID | `audio-equalizer` |\n| Category | media-tools |\n| Implementation | Registered implementation. Registration alone is not a production-quality guarantee. |\n| Browser execution | Use the visible action or interactive controls. |\n| Browser processing | Browser; see tool notes for network behavior. |\n| HTTP API | Not callable through HTTP. |\n| Browser-agent interface | run_current_tool |\n\n### Implementation notes\n\nRuns locally in your browser. Applies up to 10 bands to one recording up to 10 minutes.\n\n### Inputs and settings\n\nText input: Equalizer bands.\n\nExample or placeholder shown in the interface (not a validated fixture):\n\n```text\npeak 1000 -3 1.4\n```\n\nOne band per line: type, frequency in Hz, gain in dB and Q. Up to 10,000 characters. Review the settings before running.\n\nAccepted browser files: `.wav,.mp3,.m4a,.aac,.flac,.ogg,.oga,.opus,.webm,audio/*`. Choose one file.\n\nBrowser file-input limit: 268435456 bytes in total. HTTP limits can differ.\n\n| Setting | Meaning | Control type | Default | Constraints |\n| --- | --- | --- | --- | --- |\n| `encoding` | WAV sample format | select | \"match\" | Allowed: match, pcm16, pcm24, float32 |\n\n### Browser-agent workflow\n\n1. Open the human page in a browser that supports WebMCP.\n2. Discover the interface exposed by that page; use its actual schema.\n3. Select files on the page first when the tool requires files.\n4. Call `run_current_tool` with valid input and settings.\n5. Inspect the returned result or error and the displayed output. Retrieve files from the displayed download links.\n\nCalls do not automatically copy or download results. Browser permissions still apply. Interface availability alone is not proof of successful execution.\n\n### Planning specification\n\nOne recording up to 256 MiB and 10 minutes, up to 10 bands written in at most 10,000 characters. WAV is read with every sample intact; other formats are decoded by your browser at 48 kHz. Everything is processed on your device and nothing is uploaded. Download: WAV in the source format or the format you choose, a JSON report and a CSV response curve.\n\nThis describes intended requirements. Use the implementation notes, interface schema and observed output to determine current support.\n\n### Complete machine-readable capability record\n\n```json\n{\n \"id\": \"audio-equalizer\",\n \"category\": \"media-tools\",\n \"built\": true,\n \"requirements\": \"One recording up to 256 MiB and 10 minutes, up to 10 bands written in at most 10,000 characters. WAV is read with every sample intact; other formats are decoded by your browser at 48 kHz. Everything is processed on your device and nothing is uploaded. Download: WAV in the source format or the format you choose, a JSON report and a CSV response curve.\",\n \"implementation\": {\n \"fields\": [\n {\n \"key\": \"encoding\",\n \"label\": \"WAV sample format\",\n \"value\": \"match\",\n \"type\": \"select\",\n \"values\": [\n \"match\",\n \"pcm16\",\n \"pcm24\",\n \"float32\"\n ],\n \"labels\": {\n \"match\": \"Same as source\",\n \"pcm16\": \"16-bit PCM\",\n \"pcm24\": \"24-bit PCM\",\n \"float32\": \"32-bit float\"\n }\n }\n ],\n \"registrationFamily\": \"audio-dsp-dynamics-filters\",\n \"presentation\": \"metrics\",\n \"files\": true,\n \"accept\": \".wav,.mp3,.m4a,.aac,.flac,.ogg,.oga,.opus,.webm,audio/*\",\n \"maxFileBytes\": 268435456,\n \"inputMaxLength\": 10000,\n \"inputErrorCode\": \"AUDIO_DSP_DYNAMICS_FILTERS_TOO_LONG_BANDS\",\n \"note\": \"Runs locally in your browser. Applies up to 10 bands to one recording up to 10 minutes.\",\n \"experience\": {\n \"automatic\": false,\n \"single\": false,\n \"inputMaxLength\": 10000,\n \"inputMode\": \"text\",\n \"label\": \"Equalizer bands\",\n \"placeholder\": \"peak 1000 -3 1.4\",\n \"help\": \"One band per line: type, frequency in Hz, gain in dB and Q. Up to 10,000 characters. Review the settings before running.\",\n \"helpParts\": [\n \"One band per line: type, frequency in Hz, gain in dB and Q.\",\n \"Up to 10,000 characters.\",\n \"Review the settings before running.\"\n ],\n \"action\": null\n },\n \"mode\": \"explicit\",\n \"interactive\": false\n },\n \"execution\": \"Browser interface\",\n \"api\": null,\n \"browser_agent\": {\n \"supported\": true,\n \"name\": \"run_current_tool\",\n \"discovery\": \"WebMCP on the human page in a supporting browser\",\n \"verification\": \"See audit/API-AUDIT.md; availability is not verification\"\n }\n}\n```\n\n## Page guide\n\nShape the tone of a recording with up to 10 filter bands, see the combined response curve and compare the result at matched loudness.\n\n### How to use Audio equalizer\n\n1. Choose the recording.\n2. Write one band per line: the filter type, the frequency in Hz, the gain in dB and the Q.\n3. Apply the bands and inspect the response curve.\n4. Compare the original and processed sound with loudness matching, then download the WAV.\n\nHow can we improve this tool?\n\nReport a problem or share an idea.\n\nPlease leave out private information. Your message and the tool name go to our team via PostHog.\n\n## Useful next steps\n\n- [Audio hum filter](https://happytails.ai/en/media-tools/audio-hum-filter/) ([Markdown](https://happytails.ai/en/media-tools/audio-hum-filter.md))\n\n- [Audio de-esser](https://happytails.ai/en/media-tools/audio-de-esser/) ([Markdown](https://happytails.ai/en/media-tools/audio-de-esser.md))\n\n- [Remove background noise](https://happytails.ai/en/media-tools/remove-background-noise/) ([Markdown](https://happytails.ai/en/media-tools/remove-background-noise.md))\n\nOne recording up to 256 MiB and 10 minutes, up to 10 bands written in at most 10,000 characters. WAV is read with every sample intact; other formats are decoded by your browser at 48 kHz. Everything is processed on your device and nothing is uploaded. Download: WAV in the source format or the format you choose, a JSON report and a CSV response curve.\n\n## Band format\n\nEach line is type, frequency, gain and Q, for example peak 1000 -3 1.4. Types are peak, lowshelf, highshelf, highpass, lowpass, bandpass and notch. Gain is ignored by pass and notch filters. Q defaults to 0.707 and gain to 0. Lines starting with # are ignored.\n\n### Filters\n\nEach band is a second-order filter from the RBJ Audio EQ Cookbook by Robert Bristow-Johnson, applied in order. Settings that would make a filter unstable, or a frequency at or above half the sample rate, are rejected. Gains run from -48 to 48 dB and Q from 0.05 to 100.\n\n### Comparing fairly\n\nBoosting makes a sound louder, which can make it seem better. Use loudness matching in the player for a fairer comparison. It attenuates the louder version during playback and leaves your download unchanged. The chart shows the combined filter response; the full table and CSV contain all 120 measured frequencies.\n" }