The Shure SM58 has been the go-to mic in home and professional studios alike for decades, because it’s cheap, versatile and reliable.
Alongside the SM range, Shure also make PG and Beta series microphones. The PG series are essentially cheaper versions of each SM model, and the Beta series are basically a premium version. But if the reliable old SM58 was so great, should we really upgrade to the Beta 58A?
At first glance, the new Beta mic looks very similar to the original but it costs nearly half as much again. So what’s the difference and is it worth the extra cost?
Durability
The SM58 is famously resistant to damage, and the Beta 58A has an even stronger grille of hardened steel which should dent less when dropped. You can also be sure that while the Beta looks shinier on the outside, the electronics inside are just as robust as they always have been.
Frequency Response
This is a major factor in how a mic sounds, and can make or break how successful any particular model of microphone is. The SM58 has always sounded fine to me, and Shure seem to agree because when you look at the technical specification sheets for the SM58 and the Beta 58A, the frequency response curves look incredibly similar. The only noticeable difference is that the high end of the Beta 58A drops off slightly more slowly towards 20kHz than the SM model, so it sounds a little brighter.
Directionality
Just like the ’58, the Beta was designed to be used right next to the source to improve the separation from other instruments, PA, crowd noise etc. which makes it perfect for live use. One of the biggest differences between the two is that the ’58 has a cardioid response, and the Beta has a super-cardioid response. This doesn’t necessarily make either one better than the other, just different; a cardioid pattern rejects sound most at the rear of the mic, whereas a super-cardioid mic rejects sound most at about 60° from the rear. The Beta actually keeps a much tighter pattern in lower frequencies compared to the SM58 which is a bonus, and considering how it’s likely to be positioned for a singer in front of an on-stage monitor it’s less likely to feedback too.
Here are the polar patterns for the Beta 58A and the SM58 for you.
Beta 58A Polar Pattern
SM58 Polar Pattern
Overall, the response pattern is the biggest thing to consider when choosing between these two mics, and for on-stage use the Beta 58A seems to have the edge because you can get more gain out of it before it starts to feedback. However, for the average studio application the differences between the two are very small when you hear them side by side, so you are probably better off with an SM58 and holding on to your hard earned cash.
If it was my money, I think I’d buy three SM58’s instead of two Beta 58A’s any day.
How about you? Would you spend the little bit extra or not?
