On an iPhone, the Audio Equalizer runs in the browser, applies Bass, Mid, and Treble changes from −12 to +12 dB locally, and downloads the processed track as a new PCM16 WAV.
This iPhone workflow is for editing one file and exporting a separate copy; it does not alter the equalizer in the iPhone Music app or add an EQ preset to your library. The source is processed in the current browser tab, and the browser must be able to decode the actual codec in the file you choose.
For a direct workflow, open the Audio Equalizer, select one local track, make measured band changes, inspect the output readings, preview it, and save the completed WAV.
Choose the iPhone browser workflow
Use the browser tool when you want to alter a particular recording, voice note, podcast, or music file on the iPhone and then use the processed WAV elsewhere. It is more useful than a playback-only setting when your real goal is to export a changed file. The source audio stays local: Lizely does not receive the audio bytes, decoded samples, EQ settings, filename, or result.
Because this is file-based editing, the result is a new object. The original file is not overwritten, and the tool does not turn its three settings into a reusable preset for the Music app.
Check whether the iPhone can decode your file
Choose one browser-decodable file. The tool can work with MP3, WAV, M4A, AAC, Ogg, WebM, or FLAC only when the current browser and operating system support the codec inside the container. A familiar file extension is not a guarantee, so an M4A or WebM that fails to decode is not automatically accepted.
- Input cap: 50 MiB maximum for the selected file.
- Decoded duration: five minutes or less; the end is never silently truncated.
- Channels: one through eight accepted channels.
- Decoded sample rate: 8,000 through 192,000 Hz.
- Sample budget: no more than 30 million channel samples.
Over-limit input is rejected before filtering. A decode failure produces an error and no stale download, which prevents an older file from being mistaken for the new result.
Equalize and export a track on iPhone
- Open the page and select the source. In the browser on the iPhone, open Audio Equalizer and choose one local file. Check the type and size against the limits above; do not assume a long or high-channel-count recording will be accepted.
- Set Bass, Mid, and Treble. Enter or choose whole-number gains from −12 through +12 dB for each control. Positive values boost energy around the band center, while negative values cut it. Bass is centered at 100 Hz, Mid at 1,000 Hz, and Treble normally at 10,000 Hz when the decoded sample rate permits it.
- Apply the equalizer locally. Run the equalizer after choosing the file and settings. The tool cascades the three deterministic peaking-filter sections in Bass, Mid, then Treble order using fixed Q=1 biquads based on the W3C Audio EQ Cookbook equations. With all three controls at 0 dB, it follows a genuine flat path and copies the decoded channel samples without running a nonzero filter section.
- Check the reported output. Read the raw peak, output peak, safety scale, decoded sample rate, and frame count before deciding whether to keep the result. The tool also reports the effective band centers and output bytes. Every accepted channel keeps the same number of sample frames and is filtered independently with identical settings.
- Preview, compare, and download. Use the preview on the iPhone speakers or headphones that matter, compare it with the original at a similar perceived level, and then download the complete PCM16 WAV. The browser determines where a download is saved and may offer a Files destination; if not, use its Downloads or share workflow before opening the WAV in another app.
If a file will be imported into an iPhone audio or video app, confirm that the destination accepts WAV before relying on the transfer. The tool creates a file, not an editing session that can be reopened later.
Understand the three frequency controls
Each control is a broad peaking adjustment, not a switch that turns every frequency below or above it on or off. The fixed Q=1 setting determines how widely each adjustment spreads around its center; it is a disclosed product choice and cannot be changed on the page.
| Control | Gain range | Center frequency | What the change affects |
|---|---|---|---|
| Bass | −12 to +12 dB | 100 Hz | Energy around the low-frequency center |
| Mid | −12 to +12 dB | 1,000 Hz | Energy around the middle-frequency center |
| Treble | −12 to +12 dB | Normally 10,000 Hz; otherwise min(10,000 Hz, floor(decoded sample rate × 0.45)) | Energy around the high-frequency center |
The low-rate treble rule prevents an invalid digital filter from operating outside the available spectrum. A peaking filter changes a region around its center rather than enforcing a hard boundary. Strong boosts may emphasize noise, sibilance, rumble, or distortion already present, so a cut is often safer than stacking several boosts.
Interpret the peak and safety scale
Equalization can create samples above digital full scale even when the source did not clip. The tool measures the absolute peak across every processed sample and every channel before WAV encoding; it does not inspect and repair individual peaks in isolation.
| Check | Tool behavior | Practical meaning |
|---|---|---|
| Raw peak | Peak of the fully processed result before safety scaling | Shows how far the combined bands pushed the signal |
| Trigger | Protection is applied only when the raw peak exceeds 0.99 | Prevents the PCM encoder from chopping individual peaks |
| Output peak | When scaling is needed, the largest processed magnitude becomes 0.99 | Confirms the peak after one uniform adjustment |
| Safety scale | One factor applies across the entire processed result | The whole mix can become quieter while channel balance is retained |
A scale below 1 therefore means a protective gain reduction, not a failed preview. It is not loudness normalization and does not target LUFS, RMS, ReplayGain, or a streaming-platform specification. This is why a heavily boosted result can sound quieter after processing even though one or more bands were raised.
Review the result and plan the WAV handoff
Use the preview and reported numbers as checks, not proof of a desirable mix. Listen on the iPhone speaker, wired headset, or earbuds you will actually use, and compare against the original at a similar perceived level rather than judging only from louder output. For a device-focused comparison, the three-band equalizer workflow for earbuds explains how to keep the listening check meaningful.
- Listen for unwanted emphasis. Strong boosts may make hiss, sibilance, rumble, or existing distortion more obvious.
- Prefer a measured cut when appropriate. Negative gain can reduce a problem without forcing the combined output as high.
- Keep the source separate. Download and check the processed WAV before replacing or importing anything in your Files library.
The download is a new, uncompressed PCM16 WAV. Float samples are converted to signed 16-bit little-endian PCM and interleaved by frame. Its header records the actual channel count, decoded sample rate, byte rate, block alignment, bit depth, and complete data length. Web Audio may resample while decoding, so the displayed and written sample rate are the decoded rate, not a claim that the source container rate survived unchanged.
Know what the WAV does not preserve
The WAV keeps the complete processed sample stream, but it is not a copy of the source container. It does not retain the original MP3 or AAC bitrate, compression mode, tags, artwork, chapters, loop markers, or other container-specific metadata. It also does not preserve the original codec. If those details matter, keep the source file and use a full editor that explicitly supports metadata and codec workflows.
This tool is deliberately a compact three-band equalizer. It is not a graphic 10-band system, linear-phase mastering processor, automatic room-correction system, or a guarantee that one setting suits every recording. Use a full audio editor when you need precise center frequencies, adjustable Q, spectrum analysis, automation, linear-phase processing, loudness metering, dithering controls, codec selection, or metadata preservation.
Fix common iPhone import problems
- The browser cannot decode the file. Confirm the actual codec, not just the extension, and convert it to a format supported by your iPhone browser.
- The page rejects the recording. Compare the input size, decoded duration, channel count, rate, and sample budget with the limits.
- The preview is quieter. Check the safety scale and raw peak; a value below 1 reflects uniform protection.
- The WAV is not where expected. Check the browser’s downloads, share sheet, and Files location because destination handling belongs to the browser, not the equalizer.
If you need to diagnose a band-specific problem rather than a file-handling issue, the Audio Equalizer troubleshooting guide provides a focused checklist.