Cassette decks. How good can it get?

It's a specialist area but during the 80's in particular musicians used to demo to cassette and rough alternate versions of many famous or unreleased tracks only exist on cassette. I was in A&R back then and have demo versions of song ranging from major artists (George Michael) to unreleased tracks of very niche bands (obscure but important ones such as The Raincoats) in my collection. The Pixies distributed a cassette of their original recordings to record companies when searching for a deal. I've seen it for sale for $1,000 plus!

Nakamichi ZX9. Metal tape and the heads adjusted correctly after a degaussing.

I'm an electronic engineer that has worked in recording studios. I've worked on hundreds of professional reel-to-reel tape machines as well as digital audio recording systems - lining them up as well as repairing them. I also worked on hundreds of cassette decks (most studios had a couple of professional cassette decks and we also had rooms of domestic cassette decks for spinning out limited runs of duplicates).

If I was to setup a professional reel-to-reel deck I would expect it to record and playback accurately for months. This is not the case with cassettes. If you line up a deck accurately then take the same cassette out and play it again, the results will be different! This is because: a) the tape is too narrow; b) the cassette makes it almost impossible to reliably guide the tape evenly over the heads; c) the pinch roller is too small (but you can't fit a bigger one in the hole. The result is a great deal of speed variation, "wow and flutter".

Audio wise you can almost get a cassette to record and play OK, but only for a short while after setup. Audio wise: 1) the speed is too slow resulting in too much noise; 2) the tape is too narrow causing limitations in the bass (separation) 3) the top end is limited due to head and bias constraints; 4) single record/playback heads restrain the ability to check recordings; 5) split record/playback heads are very small and need to be manufactured with high precision (rarely achieved in practice). Also, of course each play results in oxide shed, so the tape quality declines with every play. Just about every domestic cassette player I've ever encountered leaves the factory with something wrong in it's alignment.

All of these limitations are immediately audible. I could record sound onto a studio-quality reel-to-reel and struggle to hear the difference between what comes out of the microphone and what's comes back off the tape. This is not the case with cassettes, the noise and dynamic range limitations are obvious as are the unreliable speed and limited frequency response (and that's on a perfectly lined-up device)

So, of all the popular domestic sources, cassette is the worst. And it's bad in so many ways.

My Aiwa AdF770 3 head cassette deck with Dolby B, C, Hx Pro, micro grain dual capstan, blah blah blah...makes copies that are nearly indistinguishable from the original source. No joke (as Biden would say).

Aiwa made some fantastic decks in the early 80's, ahead of their time. The one above mine, the f990, rivaled the best Nakamichi decks. I have owned mine since New in 1983. I use it often, I love it. 

Just curious: Dragon vs ZX9?