Step 1: Share your AMR files using the button above or by drag and drop.
Step 2: Click the 'Transform' button to start the transformation.
Step 3: Grab your converted AC3 files.
AMR to AC3 Transformation FAQ
How do I convert AMR audio to AC3 without losing quality?
+
Upload the AMR file and the converter chooses the AC3 codec and bitrate to match the source. Lossless AC3 (WAV / FLAC / ALAC) preserves every sample bit-identically; lossy AC3 (MP3 / AAC / OGG / Opus) defaults to 192 kbps which is transparent for most ears. AMR is a narrowband speech codec running between 4.75 and 12.2 kbps, modelling the human vocal tract rather than the full audio spectrum. AC-3 is lossy multichannel audio, normally 5.1 at 384 or 448 kbps, with metadata for dialogue normalisation and downmixing.
Is converting AMR to AC3 a second round of lossy compression?
+
Yes, and it is worth planning around. Both formats are lossy, so the AC3 encoder is working from audio that has already been through one psychoacoustic pass, and its own decisions compound the first set. At 192 kbps or above the result is still transparent for most listening. If you have a lossless master anywhere, encoding the AC3 from that instead avoids the double pass entirely.
Why does music sound so poor in this conversion?
+
Because one side of it is a speech codec rather than a music codec. It models the human vocal tract and discards everything outside telephone bandwidth, which is fine for a voice memo and destructive for anything with instruments in it. Converting away from it cannot restore the missing frequencies — they were never encoded in the first place. AMR destroys music: its 8 kHz bandwidth removes everything above telephone frequencies, and no amount of re-encoding brings it back.
What bitrate will the resulting AC3 file use?
+
Default is 192 kbps for lossy AC3; pass-through for lossless AC3. 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 AMR to AC3 reduce my audio quality?
+
If AMR is lossy and AC3 is lossless (e.g. MP3 → WAV), the AC3 is no better than the AMR — you cannot recover information already discarded. If AMR is lossless and AC3 is lossy, the AC3 codec recompresses; at 192 kbps the result is transparent for most content.
Does the AMR to AC3 converter keep ID3 / metadata tags?
+
Yes — title, artist, album, year, track number, and album art are read from the AMR container and written into the AC3 container where the format supports tags. All common targets (MP3, AAC, FLAC, OGG) handle tags fine; raw WAV does not. AC-3 is Dolby Digital, the surround format standardised for laserdisc, DVD, ATSC broadcast and cinema in the early 1990s.
Can I batch convert hundreds of AMR files to AC3?
+
Yes — drop a folder of AMR 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 AC3 keep the same sample rate as AMR?
+
By default yes — 48 kHz AMR stays 48 kHz in AC3. 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 AMR to AC3?
+
Yes — the loudness-normalize option applies ITU-R BS.1770 / EBU R128 normalization to the AC3, targeting -14 LUFS (streaming standard) or -16 LUFS (podcast standard). Useful when batching tracks mastered at varying levels.
Will my AC3 play on car stereo, iPod, and Sonos?
+
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 an AC3 codec optimized for your target hardware. AC-3 is the surround track every AV receiver, DVD player and TV decodes natively, which is why it is still the broadcast baseline. AC-3 is inefficient by modern standards and is not accepted by browsers, phones or most web players without a downmix to stereo.
Is my AMR file private during conversion to AC3?
+
Yes — uploaded AMR 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 AMR to AC3 take?
+
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 AMR → AC3 finishes in 6 to 12 minutes. Batch jobs parallelize across workers for further speedups.
