As a DJ, I got tired of record pool tracks that looked like WAVs but were actually upscaled MP3s. On a proper sound system, the high-end distortion is obvious. So I built Spectro: a macOS app that instantly tells you if a file is Lossless, Lossy, or Fake Lossless. Batch analysis, Finder integration, Quick Look support, and 100% offline. Perfect for checking unreleased promos before a gig. $39 one-time purchase.