SR
https://lh3.googleusercontent.com/-c4sAZLaBqeg/V82cOi4-t_I/AAAAAAAAEo4/BXDcZH8XQgc/s1600/Etymotic%252520Research%252520ER4SR%252520-%252520raw.png
Square Wave
30 Hz 300 Hz
https://lh3.googleusercontent.com/-j711zPFLMTM/V82cegWpxTI/AAAAAAAAEpM/lXNgMk3Lwtc/s1600/Etymotic%252520Research%252520ER4SR%252520-%25252030hz.png
https://lh3.googleusercontent.com/-CG_qh3U1TTo/V82ce1wW2OI/AAAAAAAAEpQ/tpuTCOazZrI/s1600/Etymotic%252520Research%252520ER4SR%252520-%252520300hz.png
S
http://lh3.googleusercontent.com/-p_9QRtu2jgk/VeIFXzl4nrI/AAAAAAAABgw/5QDnN4PHqy0/s1600/Etymotic%252520Research%252520ER-4S%252520-%252520raw.png
Square Wave
30 Hz 300 Hz
http://lh3.googleusercontent.com/-lbC1NzTpYlU/VeIGG6gXUUI/AAAAAAAABhk/1-dEZeJCP3g/s1600/Etymotic%252520Research%252520ER-4S%252520-%25252030%252520Hz.png
http://lh3.googleusercontent.com/-u_qCEeuaVdc/VeIGGnsva1I/AAAAAAAABhc/fzAdi931hKE/s1600/Etymotic%252520Research%252520ER-4S%252520-%252520300Hz.png
えてぃ