Tel: +86-13302916851

China Shenzhen Baichuan electronics Co., LTD

Professional manufacturer of acoustic test instruments.




Technical specification:

Noise Type :

1. White Noise: 

-3dB Bandwidth : 20Hz~100kHz

Roll off : -24dB / Oct.

Flatness : ±1dB

2. Pink Noise: 

-3dB Bandwidth : 20Hz~20 kHz

Roll off : -24dB / Oct.

Crest factor : 4 ( IEEE 219 )

3. Weighted Noise Ⅰ:  

Complies IEEE 219, CNS 4785, JIS C5531.

   4. Weighted Noise Ⅱ:  

Complies EIA 426B,

   5.Weighted Noise Ⅲ : 

Complies DIN 45573.


Voltmeter :

True rms response with Hi / Lo two ranges:

Lo Hi
100 W 0 ~ 6 V 0 ~ 30 V

Accuracy : < ± ( 1% rdg. + 1% F.S. )

Amplifier :

1. 100W output is defined at unclipped maximum output of sine wave.

2.Frequency response : 20 Hz ~ 20 kHz ±0.2dB 20 kHz ~ 100kHz ±1dB

3.Output : With permanent short circuit protection. Load Impedance : ≧3.2Ω

  • Product Detail
  • Features
  • After-sales services

 Model-8121C uses a logic circuit to generate “Pseudo Random Noise”, it is the newest and the most advanced design to generate audio white noise. It has much flatter frequency response than using diode. Model-8121C has: (1)White noise source.(2)Weighting filters.(3)Built-in power amplifier.(4)” TRUE RMS ” voltage meter circuit. It can generate five different kinds of noise’s spectrum, including White Noise, Pink Noise and three kinds of “Weighted Noise”, conforms to following nation’s standards:(1) JIS C5531, IEEE 219, CNS 4785 (2) EIA 426B(3) DIN 45573 

 Since the Noise Generator (Model-8121C) is mainly designed for loudspeaker testing, thus, it is equipped with a 50W or 100W power amplifier, and “TRUE RMS” voltage measuring circuit , to measure the “TRUE RMS” of output noise. Never use a general VTVM, AC millivoltmeter or a digital voltage meter to measure noise voltage, unless when these meters have specially noted that its AC testing function is a TRUE RMS mode, otherwise, the testing result of RMS value is only precise for a sinusoidal signal, because these meters are designed for sinusoidal RMS voltage testing. If these meters are used to test nonsinusoidal signals (including noise signals), the results of measured RMS values will be inaccurate, therefore, the 8121C is equipped with “TRUE RMS” testing circuit, to measure the noise output voltage. Since noise voltage itself is not highly stable, thus, the voltage meter’s indicator needle will have a slight deflection, don’t mistake this as 8121C was faulted.

 Model-8121C has also provide a selectable “Filtered Noise Sig. Output” terminal (9), which has the following two usages: (1) It can connect externally with another power amplifier ; (2) It can connect externally with another weighting filter, usage of an external weighting filter is: When users or other national standards required ” weighting filter network with special specification “;then, users can connect (9) to the external needed filter, for necessary filtering, then, connect the output of an external filter back to the built-in power amplifier input terminal (10) of Model-8121C, for power amplifying, thereby measuring the pre-measure

20 years industry experience 

24 hours Technical Support

Professional engineers on line response   

All life Costs Maintenance



Leave a Reply

Leave a message