so, i recorded a type 1, normal bias, on a 70s cassette deck, and it sounds FANTASTIC

Now you are going to havta record everything you want to listen to.
Better you than me.
I quit that baloney last century.

That's nice...

been there , done it , wore the tee shirt.

8-Tracks provided better bass and highs as Dolby variants outside of "A" decreased volumes in the cassette era. Spent many hours making my own mix tapes and used whatever was available including the Memorex brand. I preferred 90's, which as I recall was 45 minutes a side. 30 minutes on a 60 is not much music compared to what CD brought about. Personally, I think Dolby was a gimmick or a way to charge more money. While it reduced noise, some music lost the luster after the fact. I recall some of the later Cassette Decks - especially Nakamichi - that had quite the technological extreme look to them and were pieces of art, but all cassette decks could eat your tape. Tape eating was especially bad on 8-tracks, which is a great reason not to buy one. Even when I used alcohol and a q-tip to clean the head and spinners, some decks had a mind of their own and would eat tape for inexplicable reasons. 

Mix tapes on 8-tracks were The bomb.They mostly came apart when the splicing tape let go. Easily fixed back in the day.

My homemade 'mix tapes' from the 80s-90s still sound great on my early 90's Denon deck. 

I am surprised those old tapes still even work without jamming.  I am also surprised you aren’t getting “print through” on the tapes being that old.  

Cassette tapes were never designed for music.  Tape speed and size were for voice recordings.  Like lps.  Reel to reel tapes were designed Ed for music with limitations.   Dolby was a bandaid for the tape hiss.  Transistor radio to Walkman to portable cd players , mp3.  All compromises for audio on the go.  

I still listen to cassettes. On a Revox B 215. It doesn't get any more analogue then tape. Pre-recorded chrome tapes are fantastic.

*than

I also still listen to prerecorded tapes from the 80's primarily. They were the format.of the day. Have a big Pioneer CTF 9191 that plays beautifully. All in on analog, whatever the format, and they have held up remarkably well. And I have scored some real nice finds at my LRS for like a quarter!

ozzy62,
You beat me to it!

This is a gross exaggeration. It might sound ok at best. If you want excellent that will be different tape, and if you want fantastic - that will be better reel to reel deck.
Pre-recorded tapes sound inadequate but sometimes are listenable.

" I recall some of the later Cassette Decks - especially Nakamichi - that had quite the technological extreme look to them and were pieces of art, but all cassette decks could eat your tape. "
I bought my Nakamichi ZX7 in 1984.  I still have it.  It has never eaten a single tape.  That might be because I made all my own tapes from LPs, and used only top quality tape.