The output from the desk could hardly be described as “Line Level” since with the camera input set to ‘Line’ the on board control had to be set full-up to 10 to register a half-decent level. With the microphone input level set to -41dB, I got a more realistic signal, however, anticipating concert sound levels increasing during the course of the evening, I calibrated the input as low as it would go (-65dB). The concert got under way with full audio modulation at a midway setting of 5 on the camera, so everything seemed spot on, although neither my trusty old headphones nor my ears can cope with excessive acoustic levels these days, so I was relying on visual monitoring of sound levels. By the end of the night, this had never wavered, so seemed fine, although I was shocked to note that towards the end, the signal appeared very highly compressed. That should have alerted me to a potential problem.
Imagine my disappointment upon discovering that as the audio level was increased (perhaps 20dB) during the course of the concert, my recording had become more and more clipped due to overloading the input. However, at no time did the viewfinder monitor reach the red markers, because the input level had clearly been close to clipping from the start. Luckily I had backup from three microphones, so all was not lost, but this was a preventable problem.
I have since invested in some excellent noise-cancelling headphones (only £40 from Lindy) and will stick to the real ‘Line’ input for similar projects from now on, even if this means whacking up the gain on the camera. As for my ears, I’ve lived with them for nearly 59 years, so they’ll have to do.
HDW : It is important when recording live audio from a sound desk to record a back-up onto an audio recorder like a Tascam DR100 which records onto SDHC cards, that way if your camcorder gives you a bum recording as happened to Chris you have a clean back-up.
When I film the odd theatre production I always use a solid state audio recorder to back-up my sound, most sound technicians will give you a clean feed out of their mixing desk but you have to be prepared to have a bag of gender changers ie. XLR male to XLR male. The obvious lead would be a 1/4″ jack to XLR as some older desks only give you 1/4″ jack outs.
It’s a bit like the Scouts “BE PREPARED” arrive with a professional attitude to the job and you won’t go wrong, another expression is “BELT AND BRACES”
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