Petra,

You wrote, �g�cvarious types of sounds, but larger quakes make a huge sound and it is much like imagining an electric wire that has a huge amount of electricity attached to it and its sound is bushy or sparking with electricity�h

I take this to mean a crackling sound.

�gTo give a sound reference, the Nisqually sound was the equivalent of standing on a train station next to the track with a freight train passing going 60 or more miles per hour.�h

This would be a sort of rhythmic roar?

The NCH Tone Generator (free download) allows you to create 16 tones (or 32 if you choose stereo). By setting 32 tones (or less) to various arbitrary frequencies under 20Hz, and then setting the Waveform to Impulse, and you will get a crackling sound. Then if you switch the Waveform to Square or Saw Tooth, you will get a roaring sound, which, depending on your mix of frequencies, will sound something like a storm, or a freight train, or in-between. (Freight train sound has predominantly 10Hz-20Hz components, I think, or you could add some >20Hz).

You could play around with it and see what matches most closely. Anyway, I think the sound you hear is a variety of frequencies like this, but probably the mix, waveform, and amplitude are fluctuating. Of course I am referring to my hypothesis that EM radiation at these frequencies is being electrophonically transduced. I do not think you are hearing a �gsound�h, as people normally use the word. Having excellent low-range hearing ability cannot account for hearing such a loud sound with such a bouquet of frequencies which no one else even partially notices.

�gThe easiest way for me to describe what I hear is to imagine a fibre optic wire where the sound goes down the wire to me�cWith that [freight train sound] the fibre optic wire would have increased from tiny to 3 or 4 inches around.�h

This is more of a visual image to me than an aural one. Perhaps you are expressing the feeling of pressure that goes along with distinct sounds?

Do you ever hear sounds that are simply of one frequency, either a single musical pitch, or a simple rhythmic clicking sound?

�gThe sound I had never heard before was the ending sound of the Nisqually quake. I could hear the p-waves spreading out.�h

I assume you were hearing something prior to the quake, so I do not know what you mean by saying you �gcould hear the p-waves�h.

Ara