ステップ1: アップロード Opus 上記のボタンを使用するか、ドラッグ アンド ドロップでファイルをアップロードします。
ステップ 2: 「変換」ボタンをクリックして変換を開始します。
ステップ3: 変換したファイルをダウンロードする AIFF ファイル
Opus に AIFF 変換に関するよくある質問
How do I convert Opus audio to AIFF without losing quality?
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Upload the Opus file and the converter chooses the AIFF codec and bitrate to match the source. Lossless AIFF (WAV / FLAC / ALAC) preserves every sample bit-identically; lossy AIFF (MP3 / AAC / OGG / Opus) defaults to 192 kbps which is transparent for most ears.
What bitrate will the resulting AIFF file use?
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Default is 192 kbps for lossy AIFF; pass-through for lossless AIFF. Override to 320 kbps for audiophile or 96 kbps for voice / podcast. The choice trades file size against audible fidelity; below 96 kbps lossy artifacts become noticeable on music.
Will going from Opus to AIFF reduce my audio quality?
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If Opus is lossy and AIFF is lossless (e.g. MP3 → WAV), the AIFF is no better than the Opus — you cannot recover information already discarded. If Opus is lossless and AIFF is lossy, the AIFF codec recompresses; at 192 kbps the result is transparent for most content.
Does the Opus to AIFF converter keep ID3 / metadata tags?
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Yes — title, artist, album, year, track number, and album art are read from the Opus container and written into the AIFF container where the format supports tags. All common targets (MP3, AAC, FLAC, OGG) handle tags fine; raw WAV does not.
Can I batch convert hundreds of Opus files to AIFF?
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Yes — drop a folder of Opus files in and we process them in parallel. Premium 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 AIFF keep the same sample rate as Opus?
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By default yes — 48 kHz Opus stays 48 kHz in AIFF. If you need to downsample for compatibility (96 kHz → 44.1 kHz for CD burning), the sample-rate option applies high-quality resampling in the same encode pass.
Can I normalize loudness when converting Opus to AIFF?
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Yes — the loudness-normalize option applies ITU-R BS.1770 / EBU R128 normalization to the AIFF, targeting -14 LUFS (streaming standard) or -16 LUFS (podcast standard). Useful when batching tracks mastered at varying levels.
Will my AIFF play on car stereo, iPod, and Sonos?
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MP3 plays everywhere. AAC plays on Apple, most Android, and Sonos. FLAC plays on Sonos and Android but not on older iPods. WAV plays on everything but is huge. The advanced device-preset dropdown picks a AIFF codec optimized for your target hardware.
Is my Opus file private during conversion to AIFF?
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Yes — uploaded Opus files are processed in isolated workers and deleted within minutes. We never play back, store long-term, or share the audio content. The full retention window is in /privacy/.
How long does converting a 1-hour Opus to AIFF take?
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Same-codec re-mux: 10 to 30 seconds. Re-encode to a different codec: typically 10 to 20% of source duration, so a 1-hour Opus → AIFF finishes in 6 to 12 minutes. Batch jobs parallelize across workers for further speedups.
Why is the AIFF louder or quieter than the Opus source?
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No automatic gain change happens unless you enable the normalize option. If you observe a level change, your audio player or media library is likely applying ReplayGain or per-track normalization on playback — not us. Disable that to hear the true AIFF levels.
Can I convert Opus downloads from streaming services to AIFF?
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If the Opus download is unprotected (no DRM), yes. DRM-encrypted streams (Spotify, Apple Music tracks) are encrypted at the bit level and we cannot process them. Bandcamp, SoundCloud downloads, personal recordings, and podcast files convert cleanly.