Upload your 3GP video. PDF.to pulls the audio track out, encodes it to AC3, and gives you a AC3-only download. The video stream is discarded.
Will the audio in the AC3 match the original 3GP quality?
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If the source audio is already in a codec compatible with AC3, we stream-copy without re-encoding — bit-identical to the original. Otherwise we re-encode at 192 kbps by default for near-transparent quality.
What bitrate is the AC3 output?
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192 kbps by default. The options panel exposes 96, 128, 192, 256, and 320 kbps — pick higher for music, lower for voice.
Can I extract only part of the 3GP as AC3?
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Yes. Use the trim controls on the upload preview to set start and end times before extracting, and only that range becomes AC3.
Does the converter handle 3GP files with multiple audio tracks?
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Yes. If your 3GP has several language or commentary tracks, you can pick which one(s) to extract as AC3 in the options panel.
Will the AC3 output have the same sample rate as the source?
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Yes by default. We do not resample unless you explicitly request it. 48 kHz is preserved from movie sources, 44.1 kHz from music sources.
Is the 3GP to AC3 extraction free?
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Yes for files under 100 MB. PRO supports larger 3GP files (5 GB) and parallel batch extraction.
Does PDF.to read or store my 3GP content?
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No. The 3GP video and the AC3 audio output are deleted within an hour. Conversion runs in an isolated worker.
Can I batch-extract audio from multiple 3GP files?
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Yes — drop a folder of 3GP videos and you will get a ZIP of AC3 files back, one per source video.
Will the AC3 preserve tags and metadata?
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Title, artist, and album tags are populated from the 3GP container metadata when available. You can edit them after extraction with our audio-tag tool.
Does the converter work on streaming video URLs?
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No — PDF.to converts files you upload, not third-party stream URLs. Download the 3GP legally first, then upload it for AC3 extraction.
Why is the AC3 file much smaller than the 3GP video?
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Because the video stream (typically 90%+ of file size) is discarded. Only the audio track ends up in the AC3, which is why it can drop from gigabytes to a few megabytes.