VOB to AMR Converter

How to Convert VOB to AMR Online

1. Upload Your VOB File: Drag and drop or click "+ Add Files" to select VOB files from your DVD rip (typically capped at 1 GB per VOB segment). Batch uploads are supported, so you can queue VTS_01_1.VOB, VTS_01_2.VOB, etc. in one job.
2. Pick Constant Bitrate: Default is AMR Narrow Band (8 kHz mono, 4.75–12.2 kbps). Switch the Audio Codec to AMR Wide Band (16 kHz mono, 6.6–23.85 kbps) if you need clearer speech. Common picks: 12.2 kbps (AMR-NB max) for voicemail-style ringtones, 12.65 kbps (AMR-WB high quality) for podcast-style speech clips.
3. Set Audio Channel, Sample Rate, and Trim (Optional): AMR is mono-only at 8 kHz (NB) or 16 kHz (WB) — the dropdowns lock to those values once AMR is selected. Use Trim to pull just the line of dialogue or jingle you want (set Start and Duration in seconds) instead of converting the whole 60-minute VOB.
4. Convert and Download: Click Convert. Files process on our servers, then download stays on our servers — no watermark, no sign-up, no email required.

Why Convert VOB to AMR?

VOB (Video Object) is the DVD-Video container used inside the VIDEO_TS folder of every commercial and home-burned DVD. It muxes MPEG-2 video at up to 9.8 Mbps with AC-3, DTS, or 48 kHz Linear PCM audio in a single.vob file, segmented at 1 GB to satisfy the UDF/ISO 9660 file-system limit. AMR (Adaptive Multi-Rate) goes the opposite direction — it is a 3GPP speech codec adopted in October 1999 for GSM/UMTS voice calls, encoded at 4.75–23.85 kbps mono. Pulling AMR out of a VOB is how you turn a 4 GB DVD into a 30 KB voice clip you can drop into a 3GPP voicemail system, an Asterisk PBX prompt, or an old feature phone's ringtone slot.

• Voicemail and IVR prompts — Asterisk, FreePBX, and most 3GPP-based PBX systems play.amr natively; converting a DVD-recorded greeting straight to AMR avoids a re-encode through MP3.
• Feature-phone ringtones — Pre-smartphone Nokia, Samsung, and LG handsets read.amr from the SIM or 3GP container; a 12.2 kbps AMR-NB clip is roughly 1.5 KB per second.
• Audio evidence and dictation — Police bodycam DVDs and dictation devices from the 2000s often output VOB; AMR is the storage format mandated by some 3GPP-compliant transcription workflows.
• Archive size reduction — A 60-minute AC-3 track from a VOB is ~200 MB; the same dialogue re-encoded to AMR-NB at 7.4 kbps is ~3.3 MB. Useful when you only need intelligibility, not music fidelity.
• Android voice-memo compatibility — Android's MediaRecorder writes.amr by default for the AMR_NB encoder; matching format means no re-encoding when importing DVD audio into a voice-memo workflow.
• Embedded device playback — Garmin, older Sony Ericsson, and many automotive head units predating Bluetooth audio support AMR but not modern AAC profiles.

VOB vs AMR — Format Comparison

AMR Bitrate Quick Guide

Frequently Asked Questions

Why is my AMR file so much smaller than the VOB?

A 1 GB VOB usually carries a 192–448 kbps AC-3 track plus a 4–9 Mbps MPEG-2 video stream. AMR-NB tops out at 12.2 kbps mono and discards everything outside the 200–3400 Hz speech band, so a 10-minute dialogue clip shrinks from roughly 750 MB (full VOB) to about 900 KB. The video is dropped entirely, the audio is downsampled from 48 kHz to 8 kHz, and music fidelity is sacrificed for speech intelligibility — that is the codec's design intent, not a bug.

Should I pick AMR Narrow Band or AMR Wide Band?

AMR-NB (8 kHz, 4.75–12.2 kbps) is universally supported by GSM phones,.amr file containers, and most legacy 3GPP voicemail systems. AMR-WB (16 kHz, 6.6–23.85 kbps) doubles the temporal resolution and audibly improves speech clarity, but support is patchier — older feature phones and some PBX builds will refuse the file. Use NB unless you have confirmed the destination device or service handles WB; AMR-WB was standardized as 3GPP TS 26.171 and is also published as ITU-T G.722.2.

Will music in the VOB sound bad after AMR conversion?

Yes, intentionally. AMR is optimized exclusively for speech — it uses an algebraic code-excited linear prediction (ACELP) model that assumes a vocal tract. Music, applause, sound effects, and surround mixes all collapse into garbled artifacts at AMR-NB rates and only modestly improve at AMR-WB 23.85 kbps. If you need music, use VOB to MP3 at 128–192 kbps instead.

Can I extract only a 10-second clip without converting the entire DVD?

Yes — set Trim in Advanced Options. Enter Start (seconds from the beginning of the VOB) and Duration (length of the output clip). The conversion job decodes only the requested range, so a 10-second AMR clip from a 60-minute VOB finishes far faster than a full extract. For frame-accurate cutting before conversion, you can also pre-trim with Audio Cutter on a higher-quality intermediate.

Why does my DVD have multiple VOB files (VTS_01_1.VOB, VTS_01_2.VOB)?

DVD-Video splits each title into 1 GB segments because the original 1996 spec targets the UDF and ISO 9660 file systems, both of which have practical 1 GB or 4 GB per-file ceilings on older players. The segments are designed to play back-to-back as one continuous title, so upload them in numeric order if you want the full audio track converted in one job.

My converted AMR file is mono — can I get stereo?

No. AMR is mono-only by design, both NB and WB. The 3GPP standard does not define a stereo mode because the codec was built for one-mic cellular handsets. If you need a stereo voice file, convert to VOB to AAC at a low bitrate (48–64 kbps) instead — AAC-LC handles speech well and supports stereo.

What sample rate should I pick — 8000 Hz or 16000 Hz?

The Audio Sample Rate dropdown locks to 8000 Hz when AMR-NB is selected and 16000 Hz when AMR-WB is selected; the codec specs (3GPP TS 26.071 and TS 26.171) do not permit other rates. If you change one, the other follows automatically.

Can I keep the original AC-3 audio instead of re-encoding?

Not in this tool — output is AMR. If you want the raw DVD audio without quality loss, demux the VOB to AC-3 with VOB to AAC or convert to a lossless intermediate first. AMR conversion always re-encodes because the source codec (AC-3, DTS, PCM) and the target codec (AMR ACELP) are completely different mathematical models.