WRITTEN BY JACOB COOK
ASSISTANT EDITOR, BOOM BOX POST
Here at Boom Box Post we do a lot of wild sound effects recording. In the last year we’ve recorded props as varied as children’s ball pits, seed pods from trees, laser swords, metal impacts, metal screeches with dry ice, christmas lights, human and non-human screams, zombie moans, body drags, two different Ford Mustangs and of course: farts. We’ve used a wide variety of different equipment to accomplish these recording goals. For our most recent vehicle recording(blog post coming soon) we rented a few additional microphones and took advantage of the new gear to set up a brief microphone shootout. The microphones we compared were the Sennheiser MKH 8050, a compact super-cardiod condenser, the Sennheiser MKH 8060, a short shotgun based on the same capsule as the 8050 and the Neumann KMR 82i, a highly directional short shotgun. All three are popular choices for sound effects and film production recording. We wanted to test the timbre and character of each microphone as well as how they interacted with the acoustics in our edit bays. To test the mics we recorded a variety of sample material similar to the type of recordings we make.
For this test we recorded both male and female reading of Harvard Sentences, sample phrases that were originally created for the testing of intelligibility of telephone and audio systems. None of the samples are processed or edited outside of level adjustments and trimming.
One of the things we are testing for is compatibility with the acoustics in our edit bays. Some shotgun microphones can be more susceptible to early reflections and phase-cancellation when used indoors. From that perspective I think the Sennheiser MKH 8060 has a less roomy sound than the other shotgun mic in our test, the Neumann KMR 82i. The MKH 8050 appears to have the fullest and least-roomy sound, likely because of it’s tight polar pattern.
We record quite a few monster vocalizations, so this particular test was of the utmost importance. It was also a lot of fun to watch Jeff and Tess make faces while they imitated zombies. These samples are great for the test because unlike the Harvard Sentences, they show changes in pitch and timbre, especially the male sample. The first part of the male moan shows a distinct difference in microphone performance. The MKH series microphones have a pleasant fatness and full sound, whereas the KMR 82i sounds a little thin, possibly the result of the small room or just the sound character of the mic.
Similar to the monster samples these tests show changes in pitch and timbre. They also help show how the microphone captures the sound of the room. The sudden short screams in the male sample show this especially well.
All three microphones captured a slight tail on the end of the screams. In this test, the Neumann KMR 82i was my favorite. Despite having a slightly more scooped sound than the other two mics, it captured less of a reverb tail on the end of the samples.
The metal tests show us a lot about the tone of the microphones, especially the high frequency response. The MKH 8050 sounds a little thin and harsh on these, whereas the 8060 has a slightly fatter sound, but still a little harsh. The KMR 82i seems to soften the high frequency a little, giving slightly less harsh edge to the sound.
Ultrasonic Frequency Content
In my previous post about Designing Sound Effects with High Sample Rates I talked about using microphones that record above the range of human hearing, and the value this has in sound design. Pitch and time manipulation are two of our most powerful tools as sound designers, and ultrasonic-capable microphones can help us retain quality and high frequency content when manipulating sound in this way. To demonstrate, I slowed down several of our samples by more than 50%.
Each microphone captures a different amount of ultrasonic sound. The more high frequency content the slowed-down sample has, the greater its frequency range(each microphones spec sheet will reflect this). In this test the Sennheiser MKH 8050 is the clear winner. It’s ultrasonic recording capabilities allow the samples to retain strong high frequency content, whereas the other mics sound a little more lo-fi, due to loss in that frequency range.
All three of the microphones allowed for excellent recording quality, and any of the three could be used to record great sound effects, but each has it’s strengths and weaknesses based on sound source, and environment.