The Audix f5 is a versatile microphone from the company Audix, that is touted as being able to be used on absolutely everything. This seems like sensationalist advertising, but I will still endeavor to review it fairly.
The Audix f5 has a size and shape not unlike that of the Shure SM57, or rather the PG57 with its grill. The grill is actually nice, because although the diaphragm is slightly removed from the source no matter how close the microphone gets placed to the source. The Audix f5 has a frequency response from 55 Hz to 15,000 Hz. The special factor about the Audix f5 is that, like many of its cousins on the Audix family tree, it boasts a tighter hypercardioid pattern, which makes the Audix less of an area microphone and more of a single source microphone. It can also handle sound pressure levels up to 137 dB, a respectable number. Audix claims that this microphone is perfect for all percussion, snare, toms, guitar and bass cabinets, brass, flute, woodwinds, electric and acoustic instruments, vocals and speech, and many other things.
The microphone is also nice and heavy in the hand, and feels like it was made to last. It is a very robust microphone, and it seems like it could handle quite a bit of punishment.
In use, the Audix f5 honestly seemed quite useful, and I could see people using these to multi mic many different things. I would not be opposed to substituting these for SM57s. However, the SM57 is, in comparison to the f5, extremely cutting and robust sounding, as opposed to the almost forced natural sound of the f5. While the SM57s were not quite authentic, they had a little bit more life to them than the f5's, and I would certainly feel that coughing up $20 more for a 57 would be worth it. I however do not dislike the f5's in any way, and would still recommend them to people a little tired of the hype of the SM57.