Question about cassette player settings


Bought a used Nakamichi cassette player (LX-5) with no manual. The player offers 3 Tape Selections - EX, SX, and ZX. I'm familiar with Type I, II and IV tapes, but not with the Nakamichi settings. What do I use? Also, the player offers 2 EQ settings - 70 and 120. Again I'm at a loss about which to use since neither my pre-recorded nor blank tapes indicate an EQ setting. Can anyone give me some guidance? Thanks and have a Merry Christmas.
rockyboy
Just a little to add to the above. I've been making tapes with the same H-K deck since 1987 & have to agree with Celtic66 on not using Dolby. I also *push* the recording level so it hovers between 0 and +1 dB with peaks reaching into the red. Depending on what you use to playback the tapes with I would suggest changing the playback settings to experiment with in regards to hiss & rolloff points.

I've had very good success with Maxell XLII-S and even have some UDXLII from 1982 & '83 that still play OK. I made all my tapes to take over the road with me so only made a few metal ones, but they definitely were of better quality.

I've played these tapes in Pioneer, JVC, Alpine, Concord & Soundstream decks & they all played back differently. Have fun with it.
Good point about the equalization settings being named for and optimized to, Nak tape formulations. If the bias and equalization cannot be tweaked from the front panel like some of the better vintage 3 head decks (both my Aiwa and my NAD can), then you are WAY ahead if you pick a tape and then have a local technician adjust the bias and EQ to match the tape (just make sure it is a major brand/long running formulation).
Thanks for all the responses. I've gotten quite an education. I'm blown away by the quality of sound coming from the LX-5 using pre-recorded tapes (a variety of brands of both CrO2 and metal) that I made back in 1991 on a relatively inexpensive Nak (CRA-1 I think). I'd swear the dynamics and high and low end are better than the source CD.
Again, thanks for your help.

Rockyboy