although installation can contribute to good sound, if you start with poor equipment, there is really not much room for improvement.

also, "poor" equipment does not necessarily mean "cheap" price. similarly, "good" equipment does not necessarily mean "expensive" price.

if limited budget, go for "bang-for-the-buck" brands. research and research. or buy 2nd hand "good" brand equipment.

if wala masyado alam sa brands at setup, do consult a reliable car audio shop.