How do I convert AMR audio to Opus without losing quality?
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Upload the AMR file and our converter picks a Opus codec / bitrate combination matched to the source. Lossless target (Opus = WAV / FLAC / ALAC) preserves every sample; lossy target (Opus = MP3 / AAC / OGG / Opus) defaults to 192 kbps which is transparent for most ears.
What bitrate does the Opus file use?
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Default 192 kbps for lossy Opus; pass-through (no bitrate dial) for lossless Opus. Override to 320 kbps for audiophile output, or 96 kbps for voice / podcast where smaller files matter more than fidelity at the extremes.
Will going from AMR to Opus reduce my audio quality?
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If AMR is lossy and Opus is lossless (e.g. MP3 -> WAV), the Opus file is no better than the AMR — you cannot recover information that was already thrown away. If AMR is lossless and Opus is lossy, the Opus codec recompresses; at 192 kbps this is transparent for most content.
Does the AMR to Opus converter keep ID3 / metadata tags?
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Yes — title, artist, album, year, track number, and embedded album art are read from AMR and written into the Opus container where the Opus format supports tags (which all common ones do).
Can I batch convert hundreds of AMR files to Opus?
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Yes — drop a folder of AMR files in and we process them in parallel. Pro has more parallel workers and no per-file size cap, so a 500-file batch finishes in minutes rather than tens of minutes.
Will the Opus keep the same sample rate as AMR?
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By default yes (48 kHz AMR -> 48 kHz Opus). If you need to downsample for compatibility (e.g. 96 kHz -> 44.1 kHz for CD burning) the advanced sample-rate option handles this with a high-quality polyphase resampler.
Can I normalize loudness in the AMR to Opus step?
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Yes — the loudness-normalize option applies ITU-R BS.1770 / EBU R128 normalization to the Opus output, targeting -14 LUFS (streaming standard) or -16 LUFS (podcast standard). Useful when batch-converting tracks with varying mastering levels.
Will the Opus play on my car stereo / iPod / Sonos?
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MP3 plays universally. AAC plays on Apple, most Android, and Sonos. FLAC plays on Sonos and modern Android, less well on older iPods. WAV plays on everything but is huge. The advanced options include device presets for these common targets.
Is my AMR file private during conversion?
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Yes — uploaded AMR files are processed in isolated workers and deleted within minutes. We never play, store, or share audio content. See /privacy/ for the data retention window.
How long does converting a 1-hour AMR to Opus take?
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Same-codec re-mux: 10-30 seconds. Re-encode to a different codec: typically 10-20% of source duration, so a 1-hour AMR -> Opus finishes in 6-12 minutes on the standard pipeline.
Why is the Opus file louder / quieter than the AMR source?
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No automatic gain change happens unless you turn on the normalize option. If you do see a level change, your audio player or media library is probably applying ReplayGain or per-track normalization on playback — not us.
Can I convert AMR downloads to Opus?
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If the AMR download is unprotected (no DRM), yes. DRM-encrypted streaming files (Spotify, Apple Music) are encrypted at the bit level and we cannot process them. Sources from Bandcamp, SoundCloud, and personal recordings convert fine.