Sound Engineering
Whilst working on the rough cuts for DownStage, I realised that there is a few bits of sound which needed working on. Either the sound had a strange high frequency humming sound, which I assume to be from a phone interference, or you can hear the noise of a heater in the background during the school hall scenes (which during production we tried to turn off however were unable to due to it being set on a timer). However, I began to research how I could possibly eradicate these sound problems.
Removing Background Noise from the Radiator
After googling the best ways to remove the background noise of the radiator, I eventually came across a video on YouTube from a channel named MDTV3 which focuses on tutorial videos for Premiere. The video is called 'How to reduce Hum and Noise from video using Adobe Premiere' and it done exactly what it said by focusing primarily on one tool - altering the EQ of a sound clip.
To reduce this noise, the video explains how you should loop the part of a clip that has the noise problem, and then add the 'EQ' effect to the clip, as shown below:
Once adding the effect, the video then says to press 'Edit', which will bring up a graph showing the EQ of the clip. This will come up with one straight line - the way to remove the noise is to move part of the graph by altering primarily the mid tones, and then the low and high tones. This alters the frequency of the sound clip, helping to eradicate any noise which has either low or high frequencies. As the clip is playing on loop, this gives you enough time to find out roughly what frequency the noise you want to remove is.
In this case, as the radiator is a low-pitched sound, it meant that the frequency will appear to the right hand side of the graph (as the frequency increases the more left you go on the graph). Nonetheless, below is the EQ graph which I first originally changed to remove the low pitch sound.
The video then suggests to widen the tone you are changing to give you a much smoother sound, otherwise it may sound sharp and not work as effectively, which you can see below:
And there we have it. As already mentioned, you can alter the low and high tones within the graph to remove any other noise. For example,I had a couple of sound clips which had a high and low frequency, meaning I had to alter both sides of the EQ graph to remove this sound. However, altering this sound does have an effect on the quality of the audio - a couple of clips like previously explained which had both high and low frequency problems (from the radiator and some form of interference, perhaps from a phone) left the quality of the clip to be noticeably effected.
As the majority of DownStage was filmed in the school hall which had the radiator problem, I then perfected the EQ to eradicate the noise problem without ruining the quality of the clip. As you can see below, I made a preset and named it 'Stage EQ'.
All in all, this effect proved very beneficial for DownStage, as we had numerous amounts of minor sound issues. Additionally, altering the EQ can help to boost the quality of some of actor's voices - using the EQ generally enabled me to create a balance in pitch of our cast's voices by altering say low frequencies to alter the boost of their voices.
Phone Interferences/ High Frequency Humming Removal
The video then explains how to use the Dehummer tools on Premiere. However, on the version of Premiere I am using, there are two types of DeHummer - one in which the video explains, and then one which I preferred to use. This is mainly because the version I used gives you much more access in terms of finding the frequency of the humming, whereas the one in the video only enables you to alter it through the hertz, instead of actually finding the hum yourself.
Nonetheles, as you can see above, I moved the line on the effect until you can hear the humming sound of the clip begin to fade -this meant that I had found where on the graph this high frequency was coming from. I then dragged the graph down to an extent that it removes the frequency, but not too much that it begins to cut out all frequencies of that level, which inevitably distorts the quality of the clip by making it sound quite tinny - similar to the previous EQ effect.
This too proved to be a problem on some clips that had a much louder interference than others - for John's scene where he picks his phone up in his car, the frequency was really high, and to remove it completely, it meant that the quality of the clip would be effected, due to the need to remove the majority of the frequency.
Conclusion
All in all, this video proved very beneficial and enabled me to eradicate the majority of the sound problems that I had previously worried about. Although not quite perfect, this proved to be a great start for the sound engineering process.
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