Re: Test what you think you know: Part 2
Jay,
1) 2 1/2 inches of closed cell foam wrapped with tape certainly would be different than wind screens, which do have different high frequency attenuation and diffraction effects. Good wind screen material (open cell foam) hardly has any effect on frequency response in the usual bass region. Some test examples using different materials covering a mic below.
2) An upright bass miced from the bridge position is a boundary, as is a large speaker baffle. A mic close to the skin of a drum would have a boundary, on the side of a drum head as is common, the drum would not form a boundary. The Crown PCC (Phase Coherent Cardioid)mic element is perpendicular to the source, the Crown PZM (Pressure Zone Microphone) element is is parallel to the boundary. Both are just smaller updated implementations of the old EV "Mike Mouse" concept, which is exactly what a bridge mounted bass mic emulates if done properly.
3) Pink noise is a good source, but the proximity (1 and 3 feet) and size of the pink noise source (a small monitor) you used are not similar to a bridge miced upright bass. A dynamic cardioid mic placed on a speaker baffle of similar dimensions to an upright bass would show a completely different frequency response to your tests, and be more similar to what you ostensibly were trying to test.
4) I wrote "using closed cell foam for wrapping a mic sucks", the wrap you were "talking about" but did not post a photo of in your OP is an example of that sucky approach. Similar to people that wrap SM 57 wind screens with tape (blocking the ports behind the element)because they lost the screen retaining clip, people do a lot of sucky sound shit.
5) I wrote "tailpiece" by mistake, the tailpiece is the string attachment point at the bottom of the bass. The correct place to mount the mic is under the bridge, where the soundboard is generally loudest and has the most balanced tone, combining the body resonance and the string tone.
I certainly would not suggest that an SM58 is the ultimate microphone choice for an upright bass, though properly mounted under the bridge it can give quite good results.
There are many microphones that may do better in that position.
What are you convinced is much better?
Art
