TURNTABLE SETUP AND ALIGNMENT
Turntables are very finicky about setup and alignment, and the better the turntable and cartridge, the more finicky the they will be. A cheap turntable with a conical stylus will not vary much in sound quality from being slightly out of alignment, but a good table with a more radically-shaped stylus will sound terrible unless it is aligned just right. Still, even the cheapest and simplest of turntables should be aligned, not only to get the best possible sound, but to avoid damage to your records. Imagine making do with a $79 turntable for a year while you save up to buy a better unit, and then discovering that your old table damaged all your records!
Amongst the types of alignment necessary to make sure your turntable is playing at its best are:
Vertical tracking angle
And all this assumes that your cartridge is properly matched to your tonearm, and that the stylus is in good condition!