OK. I got around to it. As you might expect, it's going to get down to personal preferences here.
I broke out my little Mackie ProFX 8 and hooked it up to a JBL PRX 612M powered PA speaker cab. Channel EQ set flat, global graphic EQ bypassed. I put the Heil PR22 into Channel 1 and comparison mics into Channel 2.
I compared the following mics, singing my backup part to "The Sad Cafe".
Shure SM58
Shure Beta 58A
Shure Beta 87C
Shure KSM9
Right off the bat, the Heil has its own sound and doesn't sound similar to any of the others tested, even the condensers (Beta 87C and KSM9). If you look at the graphs below, that big hump at about 115 Hz on the Heil graph is very evident. The bottom is further emphasized by the steepness of the curve from 50 Hz to 100 Hz. It's a bit boomy down there. Likewise, the rise from about 3K Hz to 10K Hz is prominent. The higher component of that is pretty sibilant and, to my ear, would start to get annoying in a short time.
The flat part of the curve runs from about 300 Hz to 1,300 Hz, essentially the mid range. When I was testing the Heil, my impression was that it emphasizes the lows and highs, effectingly giving it a natural mid scoop. So you get this apparent richness down low (which may be good for miking a bass cab) and glassiness up top. If I were going to use this mic on vocals, particularly female vocals, I'd EQ some of the top off it. You'd probably want to do the same if you were miking a bass cab. In all, it's a decent-sounding mic, especially if you like the characteristics I've described. If judiciously EQ'd, I think it might do a better job than an SM57 for miking a bass cab.
As far as handling noise, it is only slightly louder than that of the Beta 58A - fairly noticeable, but not a deal-killer. The Beta 87C and KSM9 have very low handling noise.
Generally speaking, none of the Shure mics had the high frequency response of the Heil. I recognize that the Shure condenser mics (at $249 and $699 MAP) are higher-end mics, and logically "should" sound better than a $100 mic. To my ear, the Shure condensers were the best sounding of the bunch but, as I said, if you like boomy lows and glassy highs, you may feel differently.
For some voices, I might prefer the PR22 over an SM58 but, as other reviewers have noted, it's sometimes necessary to tame the high end a bit to get the harsh edge off the Heil. I'll try the Heil at practice this week on our girl singer and see how it sounds, then report back. Bottom line, I won't be sending out for more PR22s soon. They're OK, but not my flavor. The PR22 does however, expose some limitations of the SM58, which doesn't seem as lively in comparison.
My trio has been using Beta 58As, which work very well for us, but we're going to switch to Shure Super 55s, which have the same capsule and add a touch of nostalgia to our look (as if that were necessary - we're all over 55).
I'll report back with more.
BTW, what if Bob Heil had a brother Sig?
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