Lossless audio checker for macOS
The Lossless Audio Checker That Tells You What Your Files Actually Are
Spectro is a lossless audio checker for macOS that automatically detects fake lossless files in DJ libraries. Drag a folder in, get a verdict per file. Free trial for 100 files.
In short
Spectro checks whether your WAV, AIFF, and FLAC files are genuinely lossless or an MP3 in disguise. Drag a folder in — it returns a LOSSLESS, FAKE, or MEDIUM verdict per file automatically. Detection is backed by peer-reviewed research (ACM MM&Sec 2009) with 99% accuracy across 2,512 songs.
Manual check vs Spectro
| Feature | Manual check | Spectro |
|---|---|---|
| Works on entire folders at once | ✗ | ✓ |
| Automatic verdict — no interpretation needed | ✗ | ✓ |
| Supports WAV, AIFF, FLAC, MP3 | Varies | ✓ |
| Native Apple Silicon | Varies | ✓ |
| Finder tag integration | ✗ | ✓ |
| Offline — files never uploaded | ✓ | ✓ |
| Free to try | ✓ | ✓ (100 tracks) |
Who this is for
- - DJs preparing USB sticks for club gigs who need to verify 50–100 tracks fast.
- - Audiophiles who want to confirm a purchase before storing it permanently.
- - Producers checking files received from collaborators or sample packs.
What Spectro does
- - Reads the frequency spectrum of each file and detects the hard cutoff left by lossy encoding.
- - Returns LOSSLESS, FAKE, or MEDIUM verdict per file with a confidence score.
- - Batch scans entire folders — no opening files one by one.
- - Tags files in Finder with color labels for fast triage.
FAQ
What does a lossless audio checker actually check?
It analyzes the frequency spectrum of each audio file and looks for a hard cutoff above 15 kHz — the fingerprint left when a lossy encoder like MP3 discards high-frequency data. Genuine lossless files have energy that gradually rolls off toward 22 kHz. Fake lossless files show a flat wall at the original encoder's cutoff point.
Is losslessaudiochecker.com still working?
The original Lossless Audio Checker project is no longer maintained and the site no longer offers the tool. Spectro is a native macOS app actively maintained in 2026, with support for Apple Silicon, batch processing, and automatic verdicts.
Can Spectro check FLAC files as well as WAV?
Yes. Spectro supports WAV, AIFF, FLAC, and MP3. FLAC files are analyzed the same way — spectral content determines the verdict, not the container format. A fake FLAC (FLAC wrapping an MP3 source) shows the same hard cutoff fingerprint as a fake WAV.
How accurate is Spectro at detecting fake lossless files?
Spectro's detection method is based on peer-reviewed research (D'Alessandro & Shi, ACM MM&Sec 2009) that achieved 99% accuracy on transcoding detection across 2,512 songs. The only ambiguous case is 256 kbps CBR vs. high-quality VBR, which Spectro flags explicitly as MEDIUM rather than guessing.
Related guides
- How to detect fake lossless audio files on Mac
- What is fake lossless audio?
- Fake lossless checker for Mac
- Spek alternative for macOS
- Best Spek alternatives for Mac in 2026
Spectro is an independent macOS app.