Rear-Rejection Sound


Q I’ve been primarily using Sennheiser microphones, including the MKH 416 and MKH 50, for the past few years as the main mics in my sound-mixing package. I recently landed a new client for whom I’ve been mixing sound on a lot of sports events shoots where we shoot interviews on the sidelines of games at large stadiums. Depending on the location, sometimes the crowd noise is acceptable, but in the larger stadiums, the noise often is too loud and we’re forced to use the lavalier to obtain usable sound. I’ve tried most of the Sennheiser shotguns and cardioids, but I’m not up on what else is out there that might work better for this.
Cole G.
Via email

A Rear- and side-angle rejection always has been a challenge for the users of shotguns and cardioid microphones. We use shotguns for their supposedly longer "reach," a term that really means a narrow angle of acceptance in the polar (pickup) pattern of the microphone. The challenge is that if you examine the polar pattern on most popular shotgun and cardioid microphones, you quickly discover that, with that narrow angle of acceptance at the front of the microphone, there’s usually a smaller, but noticeable amount of pickup at the rear of the microphone.

At NAB 2014, Sanken, a Japanese company whose microphones have become popular with many sound mixers, introduced a new microphone that was specifically designed to reject considerably more sound from the rear of the microphone than most normal shotgun mics would reject. The Sanken shotgun lineup was already fairly well populated, with the CS-1E, a short shotgun for boom pole and camera mounting, the CS-2, a longer, higher-end shotgun, the CS-3E, a location and studio shotgun featuring exceptional off-axis rejection, the CS-S5, a three-mode stereo shotgun microphone and, finally, the CS-S10, a mono/stereo switchable camera-mounted shotgun. The new Sanken Rear Rejection Shotgun Microphone has been on the market for a few months and isn’t receiving rave reviews.

So why did Sanken add the CSR-2 to the lineup when they already had the CS-3E? Simple, the CSR-2 features a rear-rejection switch. You leave the switch off when you’re shooting in normal situations and want the fullness and richness with the slight amount of ambient sound recorded that you would obtain with a normal shotgun. But once you flip the switch on, about 60% to 75% of the sound from the rear of the shotgun magically seems to disappear. The CS-3E utilizes a similar off-axis array of other elements, but it uses three additional elements versus the CSR-2’s dual elements, and the side- and rear-rejection factor in the CS-3E can’t be switched on and off as it can be on the CSR-2. The selling price between the two microphones is the same, which is $1,450.

I had a chance to put the CSR-2 through its paces, shooting interviews next to a noisy freeway, and the noise rejection with the microphone’s rear-rejection switch in the on position is very impressive. This is accomplished by canceling background sensitivity with two microphone capsules at the low-mid frequency range, combined with a more narrow-angle directivity method at the mid-high frequency range. Narrow-angle directivity is created by the use of a long acoustic tube and a very space-efficient, square microphone element. This technology is simple, yet it really works. It’s nice to be able to switch this feature on and off for those times when rear rejection isn’t needed.

I own the Sennheiser MKH 50 and have recorded quite a bit with the MKH 416 also, and I feel that the sound quality of the Sanken CSR-2 is the same level of quality as the Sennheisers. The CSR-2, frankly, sounds a bit better than the MKH 416 to my ears, but it’s not as "big and dramatic" as the MKH 50, so my suggestion would be to borrow or rent a Sanken CSR-2 to see if it accomplishes what you need while giving you the basic sound quality that you and your clients expect.