1. Channels: Two independent output channels
2. Air conduction:
(1) Frequency: 250Hz,500Hz,750Hz,1000Hz,1500Hz,2000Hz,3000Hz,4000Hz,6000Hz,8000Hz;
(2) -10dB≤Hearing level for Testing≤110dB.
3. Bone Conduction:
(1) Frequency: 250Hz,500Hz,750Hz,1000Hz,1500Hz,2000Hz,3000Hz,4000Hz,6000Hz.
(2) -10dB≤Hearing level for Testing≤60dB
4. Signal for testing:  Pure tone, warble and narrowband noise.  
5. Frequency accuracy: The allowable error of frequency for this audiometer is ±2%.
6. Microphone: Built-in microphone or external gooseneck style microphone (optional) for easy communication with the testee. (Volume: 0-20 adjustable)
7. Display: LCD display, double-line accurate numerical display.
8. Distortion: Air conduction less than 2.5% while bone conduction less than 5.5%
9. Accuracy: Continuous attenuation / stepping 5dB, error 1dB
10. Masking: masking on the opposite side of the tested ear during air conduction and bone conduction tests.
11. Protection function: Protect the testee’s hearing from damage as much as possible
12. Computer interface: USB 2.0 data transmission interface, can be connected to the workstation forprinting test report
13. Online diagnosis: self-analysis and generation of occupational noise-induced hearing loss diagnosis report according to the “National Occupational Health Standards of the People’s Republic of China”
14. Operating environment: Temperature 10 °C ~ 40 ° C, relative humidity 30% ~ 90%, pressure 86 kPa ~ 106 kPa
15. Warm-up time: 5 to 10 minutes
16. Mean time between failures ≥1000h
17. Host size: 325mm*195mm*27mm
18. portable, lightweight: weight: the host is about 910g, the gross weight is about 4.6kg
19. Power adapter: Input 100V-240V ~ 50/60Hz 1.5A; Output DC 12V/4A
20. Built-in battery: nominal voltage 7.4V/5000mAh; continuous operation≥8 hours, standby operation mode≥1 week
21. Output: TDH 39 air conduction earphone, B71 bone conduction earphone
22. Safety standard: GB 9706.1-2007 GB/T 14710-2009
23. Audiometer reference standard: GB/T 7341.1-2010 JJG 388-2012
24. Production license number: Guangdong Food and Drug Administration Production No. 20091764
25. Standard configuration: TDH39 air conduction headset, B71 bone conduction headset, responder, powercable, USB data cable, software, audiometer, aluminum box