The German railroad plans to build 2 additional rails in our town. Since it's cheaper for them, they will build them directly thru a residential area.
We have a citizens' group here protesting against it with all means. As you can imagine there is not only a problem with the building measures (many people
will lose their estate) but also a problem with the very frequent noise of railroad traffic caused by the freight trains (the additional 2 rails are not for
I now would like to design this "sound" for the citizens group. So they can show the full impact of the noise. How would you start doing this?
Go to a location with a similar number of train tracks, and record?
Maybe record yourself trying to have a conversation as a train roars by in order to illustrate the point. That seems like the only scientific way to go about it, because if you're "designing" the sound, it's entirely up to your interpretation of what it will be like, which may or may not be accurate.
"if you're 'designing' the sound, it's entirely up to your interpretation of what it will be like, which may or may not be accurate."
I agree, you want to be careful not to take much license or it will damage the credibility of the exercise. Recording actual locations that have become what you fear your town will become is the best way to make this point and not be dismissed as intentionally exaggerating your concerns.
Take an SPL meter with you when you go to record RadioShack do a digital one that¹s reasonably priced, I think. Make notes of the levels and don¹t forget to select the correct weighting. C-Weighting takes more account of low frequencies and much of the disturbance will be from L.F. Content.
Sub-audible vibration will also play a large part in determining the aggravation level, but this is probably outside your scope. When you do the playback, use a system that can reproduce the levels that you noted on the recordings and use a pink noise source and an analyser to get the system reasonably flat, if you can, so that you¹re not accused of ramping up the bottom end to emphasise the problem.
I agree with John, make sure to use a constant reference point for your measurements (e.g. 3 meters from the sound source). Maybe you could also play other real-world examples of equivalent sounds at the same measured volume to draw a comparison: commercial jet engine, freeway roar, football crowd cheer. Nothing outrageous or spectrally incomparable, just a way to help people relate to decibel values.
Speaking not as a sound designer but as a legal videographer:
- Locate a rail line with similar houses near it
- Locate a position say 1 block away.
- Take spl measurementss there. (Yes it will be very loud next to the tracks, but
your objection is how loud it will be one or more block away.)
While a train passes carry on a conversation with someone several feet away. I would place the mic beside your head pointed as the other person and set the level, without train, for a good recording. Then actually record, same set up with the train passing by.
Even better, video tape the event.
Locate a house and do the same thing inside the house the same way.Now if the house has loose window panes or items inside the house that rattle from the train, so much the better.
Thanks a lot for your feedback. Very informative. I will try to get the best results with all this information.
Thread "Train Sound" from Sound Design List May 2008