VOX Converter — Convert VOX Audio Files to MP3, WAV and More

VOX files come from telephone systems, IVR platforms, and digital dictation machines — and they will not open in any standard media player. The format stores raw ADPCM audio with no header, so players have no way to determine the sample rate or channel count. Total Audio Converter reads VOX files directly and converts them to MP3, WAV, FLAC, or any other format you need.

Key Features

• Reads headerless VOX files. Total Audio Converter lets you specify the sample rate (8 kHz, 6 kHz, or custom) before conversion, so the ADPCM data is decoded correctly.
• Batch processing. Convert an entire folder of VOX recordings in one run — hundreds of files without manual steps.
• Multiple output formats. Export to MP3, WAV, FLAC, OGG, AAC, M4A, and other common formats. Pick the one that fits your archive or playback system.
• Command-line interface. Automate VOX conversion from scripts or scheduled tasks. Useful for call center systems that generate VOX files daily.
• Adjustable output quality. Set bitrate and sample rate for the output file. Upsample 8 kHz telephony audio to 44.1 kHz WAV for editing in audio workstations.
• No internet required. All conversion happens locally. Call recordings and voice logs never leave your machine.

What Is VOX Format?

VOX is a raw audio format used almost exclusively in telephony. It encodes audio using ADPCM (Adaptive Differential Pulse-Code Modulation), a codec designed for compressing voice at low bitrates. A typical VOX file stores mono audio at 8 kHz — the standard sampling rate for telephone-quality voice.

The defining characteristic of VOX is that it has no file header. Standard audio containers (WAV, MP3, FLAC) include a header block that identifies the codec, sample rate, channel count, and bit depth. VOX has none of this. The file is a bare stream of ADPCM-encoded samples. A media player that opens a VOX file has no information about how to decode it — which is why VLC, Windows Media Player, and most other players either refuse to open VOX files or produce distorted noise.

VOX files originate from IVR (Interactive Voice Response) systems, analog and digital dictation machines, telephony gateways, and call recording software. Formats like Dialogic VOX (used in Dialogic telephony boards) and Rhetorex VOX follow the same headerless ADPCM convention. The typical file extension is .vox, though some systems use .adpcm or even no extension at all.

To decode a VOX file correctly, the player or converter must be told the sample rate (usually 8000 Hz) and that the audio is mono. Without those parameters, the decoded audio will play at the wrong speed or sound like scrambled noise.

How to Convert VOX Files

1. Download and install Total Audio Converter. The 30-day trial is fully functional — no email or credit card required.
2. Open the program. The left panel shows your folder tree. Navigate to the folder containing your VOX files.
3. Check the boxes next to the files you want to convert. Use Ctrl+A to select all files in the folder at once.
4. Click the target format in the toolbar — MP3, WAV, FLAC, or another format.
5. In the conversion settings dialog, set the sample rate to 8000 Hz (or the actual rate your recording system used) and verify the channel setting is Mono. Choose the output folder and click Start.
6. The converter decodes each VOX file and saves the output to the folder you selected. A progress bar shows status per file. The converted files open in any standard media player.

Command-Line Conversion

Total Audio Converter includes a command-line version for server use and scripted automation. Example command:

TotalAudioConverter.exe C:\CallRecordings\VOX\ C:\CallRecordings\MP3\ -c MP3 -b 64 -freq 8000

This converts all VOX files in the source folder to MP3 at 64 kbps with an 8 kHz input sample rate. You can wrap this in a .bat file and run it with Windows Task Scheduler — useful when a call center system deposits new VOX files to a folder nightly and you need them archived as MP3 by morning.

Why Use Total Audio Converter?

Handles the headerless format correctly

Most audio tools fail on VOX files because there is no header to read. Total Audio Converter treats VOX as a raw ADPCM stream and uses the sample rate you specify. This produces correctly-paced audio, not the chipmunk-speed or slow-motion distortion that results from wrong rate assumptions. The setting is saved per conversion profile, so you only configure it once for a batch.

Processes large archives in one pass

Call centers and dictation systems accumulate VOX files over months or years. Converting them individually is not a realistic option. Total Audio Converter processes entire folder trees in a single operation. Enable recursive mode and it descends into every subfolder, converting and replicating the directory structure in the output location.

Output quality is under your control

The default 8 kHz source audio is telephone quality — adequate for voice intelligibility but not ideal for archiving or editing. Total Audio Converter lets you upsample to 16 kHz or 44.1 kHz WAV for use in audio editors. For storage-efficient archives, 64 kbps MP3 mono preserves voice quality at a fraction of the WAV file size.

Works without an internet connection

Call recordings often contain sensitive business or medical information. Total Audio Converter runs entirely on your machine. No files are uploaded to any server. This is a practical requirement for healthcare, legal, and financial environments where data residency matters.

Scriptable for automated workflows

The command-line interface accepts all conversion parameters as arguments. You can build a fully automated pipeline: IVR system writes VOX files to a watch folder, a scheduled .bat script converts them to MP3, and the MP3 files are moved to a playback or archiving location. No manual steps, no GUI required.

Online Converters vs Desktop Converter

When Do You Need a VOX Converter?

• Archiving call center recordings. Call center platforms record conversations in VOX to save disk space. After a retention period, recordings need to be archived in a standard format. MP3 or WAV can be opened by any compliance or quality-assurance team without specialized telephony software.
• Retrieving dictation machine recordings. Older digital dictation devices — used by doctors, lawyers, and executives — store voice memos as VOX files. When the device is replaced or the software is discontinued, the VOX files become inaccessible. Converting to MP3 or WAV makes them permanently retrievable.
• Re-encoding IVR audio for a new system. When migrating to a new IVR platform, existing VOX prompt files must often be re-encoded in the format the new system expects — typically WAV PCM at a specific sample rate. Batch conversion handles the entire prompt library at once.
• Editing voice recordings in an audio workstation. Applications like Adobe Audition, Audacity, and Reaper do not open raw VOX files. Converting to WAV first is the standard step before any editing, noise reduction, or transcription work.
• Sending recordings to transcription services. Transcription platforms and speech-to-text APIs accept MP3 or WAV. VOX files must be converted before upload, and the sample rate must be declared correctly or the transcription will be garbled.

Total Audio Converter Customer Reviews 2026

"We had seven years of call recordings stored as VOX files from our old Dialogic system. The new platform uses MP3 exclusively and none of our compliance team could open the archived calls. Total Audio Converter batch-converted over 40,000 files in a weekend. Setting the sample rate to 8000 Hz in the profile was the key step — after that every file came out clean and playable. The command-line mode let us script the whole thing."

Sandra Kowalski Call Center Operations Manager

"The clinic switched dictation systems and left us with a backlog of VOX recordings that the new software could not read. I needed WAV files for our transcription service, which does not accept VOX. Total Audio Converter handled the conversion without any issues — I pointed it at the archive folder, set 8 kHz mono, chose WAV output, and let it run. Every recording transcribed correctly afterward. Straightforward and reliable."

Dr. Michael Reinhardt Medical Transcriptionist

"We manage an IVR system that generates VOX prompt files, and every time the marketing team wants to edit a prompt they send me a VOX file I have to convert before they can open it in Audacity. I set up a scheduled .bat script using Total Audio Converter's CLI that auto-converts any new VOX file dropped in a watch folder to WAV. Saved me from doing it manually. Would give 5 stars but the documentation for the command-line parameters could be more detailed."

James Oduya IT Administrator, Telecom Company

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