Type 8405-C (Replaces Types 8706 And 7771)  BK Connect CPB

Type 8405-C (Replaces Types 8706 And 7771) BK Connect CPB

This BK Connect application performs 1/n-octave – or constant percentage bandwidth (CPB) – analysis. Data can be acquired from just one and up to hundreds of channels connected via data acquisition hardware to a PC, which records the signals. This software analyses the time data as it is replayed. It can perform multiple types of parallel analysis on the same data, such as analyzing vibration data at a different bandwidth to acoustic data.

1/n-octave analysis using 1/1, 1/3, 1/6, 1/12 and 1/24 octaves is often preferable to fast Fourier transform (FFT) analysis when analyzing noise.


  • Analysis of recorded sound and vibration time data
  • Vehicle noise, vibration and harshness (NVH) investigations, such as benchmarking
  • Acoustic measurements for calculating equivalent sound level (Leq) spectra on household consumer items such as washing machines

The software displays time data in an intuitive interface where users can efficiently get an overview of the data. To find relevant recordings, you can search for signals in the file name, such as ‘Drivers ear’. By playing back audio and viewing the complete time history, you can make an intelligent selection of signal groups and time ranges for analysis. Features like synchronized cursors help make selections.


  • Simultaneous calculation of overall level, both weighted and unweighted
  • Exponential or linear averaging
  • Spectrum and level vs time
  • Exponential averaging includes slow and fast modes, covers tau range from 1/2048 s to 512 s
  • Overall weighted or unweighted level (A, B, C, D or G) weighting
  • Level vs time via frequency band extraction

This software has an overall level analyzer that performs a broadband analysis equivalent to a sound level meter, fulfilling relevant requirements of IEC 651, IEC 61672 and IEC 60804 for a Class 1 instrument. This software fulfils the requirements of the standards DIN 45651 and ANSI S1.11–2004.


  • Graphical, drag-and-drop analysis process chain
    All BK Connect analyses use a graphical process-chain concept for setting up the post-recording analysis process. This includes individual elements for filtering, analysis, display and storage of results. each is individually configurable. Process chains can be exported to a file and emailed to allow others to repeat a defined, standardized process.
  • Automated processing
    To maximize productivity, BK Connect enables batch processing of sequenced or parallel analysis of multiple sets of imported data. Time data can also be automatically imported from a network drive, and you even have the option of automatic reporting.


  • 1/n-octave spectrum vs RPM – with BK Connect Order Analysis Type 8405-E
  • Pseudo real-time analysis when linked to BK Connect Time Data Recorder Type 8400


  • BK Connect Time Data Recorder Type 8400
  • BK Connect Data Processing Type 8403 or BK Connect Data Processing Specialist Type 8404