SENSE AND SENSITIVITY

摘要

According to the Audeze website [in late June] the sensitivities of the LCD-2, LCD 3 and LCD X are 93dB, 93dB and 95dB respectively for 1mW input; and their impedances are 70,110 and 22ohm. Translating into the more relevant voltage sensitivity that we measure, these figures are equivalent to 104.5dB, 102.6dB and 111.6dB SPL for 1Vrms input. But our measurements tell a rather different story: sensitivities of 106.0dB, 109.4dB and 115.1dB respectively for 1Vrms input at 1kHz, and impedances of approximately 59,48 and 20ohm. To what extent the progressive increase in sensitivity is due to the progressive decrease in impedance we can assess by calculating current sensitivity instead - since it is the current flowing through the voice coil that gives rise to the force on the diaphragm. Doing this we find the figures are 107.4dB, 109.0dBand 107.1dB, all for 20mA rms. On this basis there's little to choose between the LCD-X and LCD-2.