Recording thunderstorms can be very difficult, with the level of difficulty being inversely proportional to their distance away; with the prize capture and most difficult being a direct strike on the microphones, only joking of course!
In my previous post ‘Summer Storms’ I mentioned the fact that my field recording sessions covering the period 14th, 15th, 16th, 23rd & 25th June 2016 at Saham Hills, Norfolk, England did not all go to plan, so I will explain.
The storms during the course of those 5 days mentioned were very sporadic and unpredictable, with them suddenly appearing and disappearing just as quickly. The 23rd June however turned out to be the most productive day, with numerous intense storms accompanied by torrential rain, hail and frequent cloud-ground lightning strikes, but this is all in hindsight; the problem beforehand was of predicting when and where they would appear, or as with the previous days would they merely ‘pop-up’ and pass by some 5 – 10 miles away. Nevertheless, I was prepared and waiting with the Edirol R-4 recorder and RME Quadmic preamp connected to the mid-side stereo microphone array and Sennheiser long shotgun microphone via long cables and also the ‘drop & recover’ field recording package containing the Olympus LS11 with its external XY microphone array of Soundman OKM II Classic capsules and A3 preamp, so what could go wrong – I was completely covered?
What I failed to predict was how quickly the thunderstorm would appear, its intensity and its distance away. As mentioned previously the level of difficulty in recording thunderstorms is inversely proportional to its distance away, and in this case the distance away was zero miles as it appeared directly overhead with cloud – ground lightning strikes within 100 yards, so the level of difficulty was ‘difficult’.
Unfortunately the recordings of the closer thunderclaps captured on the ‘drop & recover’ package were completely distorted as the Soundman Classic II microphone capsules are only rated to 103 dB and I would estimate these close strikes being in the region of 120 – 130 dB; so whatever gain levels, pads or limiters* had been set on the A3 preamp or Olympus recorder , the signal had already been distorted at the microphone.
‘Drop & Recover’ Audio Clip (warning it’s loud!)
However, the mid-side stereo array, RME Quadmic and Edirol R-4 recorder handled the loud thunderclaps much better, although still with some slight distortion, as the Rode NT1A large capsule microphone can handle up to 137 dB.
Edirol R-4 Audio Clip
Despite the frustration of failing to capture those prize close thunderclaps at maximum dynamic range with no distortion, I do prefer the overloaded track captured by the ‘drop & recover’ package, as it’s exciting, full of life and guaranteed to remind me in later-life of what happened and the excitement of that particular day!
* I never use limiters whilst recording as they kill the dynamic range, producing a dull, lifeless recording, and it’s so much more fun trying to get the gain levels set just right!