Frequency Response


Just wondering if there are some general guidelines/range (minimums) one should look for in regards to frequency response. Is a 30hz-30khz fairly standard?
gwng8
Extension at either end is less important than linearity in-between. Meaning the amount of +/-, or how 'flat' they measure. Personally I'd say at most +/- 3db over it's operating range, and +/- 1.5db being what I insist upon myself.