A fake 320kbps MP3 is a file first encoded at a low bitrate such as 128kbps, then re-encoded at 320kbps. The tag and the file size say 320, but the audio still stops where the low-bitrate encode stopped. In Bangerz Army's own test on 8 September 2026, a 128kbps encode stopped at 16.87 kHz and a genuine 320 at 20.25 kHz.
What is a fake 320kbps MP3?
A fake 320 is a 320kbps MP3 whose audio came from a lower-bitrate MP3. The file is also called an upscaled MP3. MP3 is a lossy format: a 128kbps encode deletes most of the high-frequency detail (the air on hi-hats, cymbals and vocal sibilance) to make the file small. Re-encoding that file at 320kbps makes it bigger and rewrites the tag, but the deleted detail never comes back.
A photocopy of a blurry photo on a high-resolution setting is the same problem. The copy is bigger, and the blur is still there.
Why does a fake 320 show 320kbps in rekordbox or Serato DJ Pro?
rekordbox and Serato DJ Pro read the bitrate from the file header, and a re-encode writes a correct 320kbps header. The file size matches a 320 too, because the re-encode spent 320kbps of data describing the same missing top end. Nothing in the track list can show a fake 320. Only the audio itself can.
What frequency cutoff does each MP3 bitrate leave?
Each MP3 bitrate leaves a cutoff: a hard edge above which the audio is silent. At a 44.1 kHz sample rate, 128kbps stops at 16.87 kHz, 192kbps at 18.93 kHz, 256kbps at 19.58 kHz and 320kbps at 20.25 kHz. The table below is Bangerz Army's own measurement, made on 8 September 2026 for the Tune Check tool: a full-band pink-noise source encoded with ffmpeg 8.1.1 (LAME encoder) at each bitrate, then measured by the same detector Tune Check runs in the browser.
| MP3 bitrate | Cutoff at 44.1 kHz | Cutoff at 48 kHz | |---|---|---| | 96kbps | 15.50 kHz | 15.37 kHz | | 128kbps | 16.87 kHz | 16.87 kHz | | 160kbps | 17.56 kHz | 17.61 kHz | | 192kbps | 18.93 kHz | 19.09 kHz | | 256kbps | 19.58 kHz | 19.81 kHz | | 320kbps | 20.25 kHz | 20.54 kHz | | Source FLAC | No cutoff (full band) | No cutoff (full band) |
A re-encode keeps the cutoff of the first encode. A fake 320 made from a 128kbps file still stops near 16.87 kHz, about 3.4 kHz below a genuine 320.
Does a low cutoff prove the exact bitrate of a file?
No. A cutoff proves how much of the frequency range a file holds, not which bitrate made it. In the same 8 September 2026 test, pink noise encoded at 192kbps stopped at about 19 kHz, but a dense, loud music track encoded at 192kbps stopped at 16.0 kHz, because the encoder drops the top band first when the music needs the bits elsewhere. For that reason Tune Check says "its audio stops where a 128kbps encode stops", and never "this file is 128kbps".
Tune Check passes a file as a real 320 when its audio reaches 19.5 kHz. The bar sits below the measured 20.25 kHz on purpose: some encoders other than LAME place their 320 cutoff a few hundred hertz lower, and calling a genuine file fake costs a DJ more than letting a borderline file pass.
How do you check if an MP3 is really 320kbps?
To check an MP3, look at its frequency content, not its tag. Three ways work, from quickest to slowest:
- Run the file through Tune Check. Tune Check is a free Bangerz Army tool that analyses up to 20 files per run on your own device, so the audio never leaves your computer, and shows the spectrogram behind each verdict: "Real 320", "Not actually 320", or "Lossy hiding inside" for a lossless file made from an MP3.
- Open the file in any free spectrogram viewer. A genuine 320 shows activity up to about 20 kHz. A fake 320 shows a flat, dark band above a straight horizontal edge, usually between 16 and 17 kHz for a file that started at 128kbps.
- A/B the file against a known genuine copy on a club PA or good studio headphones. The fake 320 sounds duller on cymbals, hi-hats and vocal sibilance. This test needs a reference copy and a track you know well.
Where do fake 320s come from?
Most fake 320s come from a chain of conversions, not from fraud. A track is ripped from a low-bitrate stream, shared at 128kbps, then converted to 320kbps by someone who wants a uniform library format. Every later copy inherits the same cutoff and the same wrong label.
DJ pools and download sites differ in how they check source quality before a file reaches a subscriber. A DJ pool that batch-converts promo files without checking them can ship fake 320s that nobody spots in a file browser. The missing top end only shows on a sound system good enough to expose it, which at a paid gig is the system you play on.
Bangerz Army delivers 320kbps MP3 files. Run any download through Tune Check if you want proof.
Frequently asked questions
Can you hear the difference between a real and a fake 320?
On laptop speakers or cheap earbuds, often not. On a club PA, a monitor system or good studio headphones, yes: a fake 320 has a duller top end, most audible on cymbals, hi-hats, vocal sibilance and reverb tails, and easiest to hear in a direct A/B against a genuine 320 of the same track.
Does converting a fake 320 to WAV or FLAC fix it?
No. Converting a lossy MP3 to WAV or FLAC keeps every bit that is left and adds nothing back. A 128kbps MP3 converted to FLAC still stops near 16.87 kHz; the FLAC only stops further loss from that point on.
Can a FLAC or WAV file be fake too?
Yes. A FLAC or WAV file made from a low-bitrate MP3 keeps the MP3's cutoff inside a lossless format. Tune Check reads FLAC and WAV files the same way as MP3 files and labels a lossless file whose audio stops at an MP3 cutoff "Lossy hiding inside".
Is a 256kbps MP3 a fake 320?
No. An MP3 honestly tagged at 256kbps is a lower-bitrate file, not a fake. Tune Check reports such a file as "This is not 320 kbps" and keeps the "Not actually 320" verdict for files whose tag claims 320kbps while their audio stops lower. A file tagged 320 whose audio stops between 18.2 and 19.5 kHz is flagged as doubtful too, because that range is where 160 to 224kbps encodes land.
Is it illegal to label a fake 320 as a real one?
A wrong bitrate label is a quality problem, not usually a legal one. The cost for a working DJ is a track that sounds thin in front of a paying crowd, and a library where every file needs checking by hand.
Sourcing tracks you do not have to double-check is the subject of how to build a DJ music library. To check the files you already own, open Tune Check: free, and the audio stays on your device.
Image credits. All photos via Pexels under the Pexels free-to-use licence. Hero: Hendrik B. Inline 1: Egor Komarov. Inline 2: Erik Mclean.