"A throaty noise when I press the gas peddle past half or hard" acceleration. It is hard to tell exactly what you mean. Is there a specific place you think the noise is emanating from?
Could be the previous owner altered the exhaust pipes or muffler. If you have no Diagnostic Trouble Codes, DTC then you should be fine. You can get free scans at most auto parts store, but they will try to sell you something you probably don't need.