Hi,
I know very little about sound recordings, but would be grateful for any help with this problem.
I am working with recordings of some bird sounds. These are male bitterns which make a loud booming sound to attract females.
The booms are around 150Hz. and have been recorded as .wav files.
I can hear these booms very loud and clear on the speakers of my Windows 7 desktop.
I have emailed a shortened version of the sounds to two colleagues (as a .wav file) and they can hear the booms loud and clear.
I was talking to a friend on the telephone and describing my work and he wanted to hear the booms.
I held my phone close to the bass speaker and played the file - but he could hear nothing.
I emailed the file to him, and again he could hear nothing. I have since emailed the file to 3 other friends and all have been able to hear some faint higher frequency bird sounds, but not the loud low frequency booms.
I’ll attach a screenshot of what I can see on Audacity and the sound file.
Any explanation or suggestions how I can convert this sound file so that it can easily be heard by anyone would be appreciated.
I suspect that the problem is simply that small speakers can rarely reproduce low frequency sounds. Perhaps a Christmas gift card for purchasing headphones could be a solution?
(my laptop speakers are about 30 dB quieter at 500 Hz than at 1000 Hz, and below 100 Hz there is no audible sound at all. Phones are generally optimised for the 300 Hz to 5000 Hz frequency range).
If your screenshot/sample file is representative of the entire file, your signal level is low (not surprising with a bird recording). The Amplify effect can bring-up the volume, which may help a little. Boosting the volume will also boost the background, but no worse than if you turn-up the volume during playback.
This is exactly why the Audacity LF-Rolloff AudioBook Voice filter works so well. It strips off any tones lower pitch than 100Hz which can screw up the company sound technical measurements…but absolutely nobody can hear them.
I’ve never found a solution. Part of the problem is you think your system is perfect and everybody else must be crazy. I so want to create a test sound clip that can tell you how well your speakers are doing.
I once called it the sound a large pillow makes when somebody hits you with it.
