ePanorama.net

Is the cartridge a MM (moving magnet) or MC (moving coil)?
From your post i guess that the cartridge is a MC, and your receiver has only an input for MM.

If that is the case, you have 3 options:
1. Get a better receiver/amplifier with a MC input.
2. Get a MC pre-amp and connect the output to appropiate input on the
receiver (could depend of the type of preamp, read the manual)
3. Buy a MM cartridge for the turntable. Mind that MC cartridges produce better sound, but if your receiver is a sub 200 euro unit (which it probably is, if it lacks an MC input ), i don't think you will hear the difference.

I recently inherited an old 1976 Panasonic Technics SL1700 turntable in almost mint condition. The cartridge on it is an unknown Audio-Technica (I would also like to know the type of quality Audio-Technica cartridges provide). Anyways, the reciever it is connected to is a cheaper Sony reciever that is around 5 years old.

When playing records, it sounds almost as if the sound is un-amplified (with the volume all the way up it sounds as if it is only half way).

I have heard things about it matters which channel you run through, other things about using different connectors, some things on pre-amps.
Not to mention this is my first attempt at the turn-table, and am not even aware what a bad cartridge or bad needle even effects.

I guess my question is, how/what do I fix or what should I try to fix first(the cheaper the better for now). PLEASE HELP... I CANT LISTEN TO ZEPPELIN THAT ISNT LOUD.