User's Manual

TITLE:
Product Specification for HS-W1
Revision:
001
Date:
11/30/2011
Prepared by:
Approved by:
Page: 11 of 18
本文件為美律實業股份有限公司專有之財產，非經書面許可，不准透露或使用本資料，亦不准複印，複製或轉變成任何其他形式使用。
The information contained herein is the property of Merry and shall not be distributed reproduced, or disclosed in whole or in part without prior written
permission of Merry.
4.2.4 Idle receive noise (dBA)
The idle receive noise shall be measured at the maximum volume step. This must be measured with
a quite (all zero) signal being sent. The final ERP spectrum must be A weighted and power summed to
achieve the final dBA value. Following the ITU-T p.310 recommendation, It shall not exceed -56
dBPa(A) or 38 dBA SPL measured on an IEC711 coupler with the DRP-to-ERP correction applied.
4.2.5 Send path
The send microphone path is to be measured on a HATS with the send path representing the transfer
function from the pressure at MRP to the microphone signal. Frequently in DSP enabled headsets,
the send path cannot be measured with tones, but must be measured with a broadband artificial speech
signal into the hats mouth simulator.
The send path requirements are to be measured with an in-speech SPL of -4.7 dBPa(A) or
89.3 dBA SPL 3 dB at MRP. The signal sent into the artificial mouth must be equalized to
compensate for the non-flat response of a HATS artificial mouth to achieve a nearly flat response
between the digital representation of the test signal and the MRP pressure.
4.2.6 SLR
The SLR is the loudness loss in the send direction from the acoustic signal at the mouth reference
point to the send signal at the digital reference point. Refer to Annex A and ITU-T Recommendation
P.79.
The SLR shall be calculated using the 1/3
rd
octave sensitivity data collected from the send frequency
response measurement. Use equation [A1] of Annex A and bands 1 to 20, of Table 14. The terminal is
designed to have a SLR = 15 dB 3 dB
4.2.7 Send mask
The headset send frequency response shall fall between the upper limit and the lower limit given in
the following Table and Figure. The limit curves shall be determined by straight lines joining
successive co-ordinates given in the table, when frequency response is plotted on a linear dB scale
against frequency on a logarithmic scale. Note that the frequency response mask is a floating or “best
fit” mask.