Lynx Recordings – Revisited

You may remember the Blog on Lynx recordings made in Macedonia by Reynard (see posting of 13th Sept 2011). These have been reprocessed by another recordist, but still using WaveLab as the editing software, using two different approaches as described below.

The original recording was made in MS, but the sound seemed ill-focused. It was processed with the following steps.

  1. It was separated back into MS then recombined with less Side mic, to produce a more tightly focused version, with regard to the Lynx calls.
  2. The result was processed with a Sony Audio restoration plug-in (SoundForge 9) to remove the top end hiss.
  3. EQ to further reduce hiss above 10kHz, and also LF below 100Hz.
  4. The interval lengths between Lynx calls were reduced by selecting the individual calls and crossfading them together.
  5. Resample and dither to 16 bit 44kHz
  6. Create an Audio Montage ( i.e. a mix) with the edited file together with background tracks of forest sounds and wind tracks (Just a bit of forest and a bit more wind).
  7. Boost the Lynx calls (only) by 3dB using ‘level envelope’ (A bigger boost produced obvious pumping)
  8. Render down to a final file
  9. Code as mp3.

Listen to the processed recording here:

      Lynx-1

The result is less obviously a mix than Lynx + forest, but probably not as good as Lynx + wind (see blog post of 13th Sept 2011 for comparison recordings). However, looking at the audio spectrum for the final mix, you’d be very hard put to pick up any edit points.

A second approach gave a different result:
As before (see above) the width of the sound stage was reduced and the file length was shortened.

Listen to the processed recording here:

      Lynx-2

A Sony Noise reduction plug-in, in 2 stages was used to process the recording. This captured a noise profile from a background part of the track and then the background was subtracted from the file as a whole. If you listen to the result we hope you agree that it is pretty effective. The point about this approach is that the final recording has had no spectral editing and no mixing with any other file (wind, forest etc) to try and mask the background noise.

Listen to the processed recording here:.

      Lynx-3

Although from a bioacoustic standpoint, the shortening of the inter-call periods is not good practice, this was done for the purpose of illustrating sound processing techniques. What do you think to the quality of the processed recordings, especially when compared to the original field recording?

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