Yeah, first off, get a clean, uncompressed reference of that 1985 session – like a high‑res WAV from a verified source. Then run both the cassette bit and your reference through a fingerprinting library like Chromaprint or Acoustid; they’ll give you a hash of the audio content. If the hashes line up to, say, 98% or higher, you’ve got a strong case for authenticity. Now, if you’re hunting for tampering, watch for any hash “jumps” in the middle of a track – that could mean a splice. Also, look at the spectral signatures: a sudden drop in high‑frequency energy or an abrupt change in the reverberation pattern is a classic sign of a cut‑paste trick. Some folks use phase coherence checks; mismatched phase over a short window can flag a digital edit. And don’t forget to check the metadata on the cassette’s recording machine (if you can get it). If the serial number or firmware version doesn’t match the era, that’s a red flag too. I’ll probably over‑analyze all this, but hey, at least I’ll finish the analysis… maybe.