Hi Shana!
First, lets talk about the deck you already have; it may serve you well enough for now, if it’s just a matter of making copies of your work, and not some big recording enterprise. You asked me about metal tape; cassette decks have a knob or button on them that will change your BIAS. The bias tells the recorder what type of tape you’re using and will adjust it’s internal settings accordingly. It should give you 3 options: normal, chrome, and metal. If your deck does not have these options, then yes, you will most certainly need a better deck. I’ve not been out shopping for a deck in years, and this is mostly due to buying a good one years ago, that’s held up well. Mine is an NAD, and I’ve always been very happy with it. I can make dubs from CD’s that sound so close to the original, that I would challenge anyone to tell the difference. Metal tape by the way is just a type of tape formulation, just like chrome or normal. Browse through the blank tape section the next time you’re at the music store and see what different kinds you can spot. I’ve always been real partial to Sony for metal and normal bias, and TDK for chrome. If you want to make tapes for other people to hear on their own little walkmans and that type of thing, then you should make their copies from normal bias tapes recorded with Dolby B. Most of these cheap walkman as well as car decks don’t have a very good frequency response, especially in the high end, so if they play back a tape that’s been encoded with Dolby B, and leave the noise reduction OFF, they’ll get a boost in the high end that can be helpful. On the other hand, if they play the tape back on a good home cassette deck, then they will probably want to engage the Dolby B, so that they’ll hear less tape hiss. Stay away from Dolby C and S when making tapes for other people to hear, because if they play them back on cheap units without the noise reduction turned on, the tape will sound awful.
If you’re making actual two-track mixdowns on tape for yourself and want a good one from which to dub copies for others, then you should of course make the best sounding tape possible, and this will entail using metal tape and engaging Dolby C or S. Make sure you have a good hot level on the tape deck; recorded slightly above O VU on average, and only clipping the highest range on the meters occasionally.
Since you have a computer, you might want to simply run a line out of your multi-track machine into the line input of your computers soundcard, and burning wav files. After you get things sounding the way you want, you could then run a line out of the soundcard into your cassette deck for making copies. Recording on computer takes a bit of know-how though, along with some special software and at least a SoundBlaster Live card. The SB card is about a hundred bucks, and some software for recording comes with it, but you’ll want to use some better software eventually for editing purposes. I would recommend downloading Cool Edit for that. It’s 70 dollars and well worth it.
By the way, you might also look at DAT stand alone decks for mixing down to. I’ve seen them as cheap as 300 or so, and they sound great and would sure make the job easier for you. You could always dub cassette tapes from the DAT’s.
Lot’s-o-luck