Any analysis of single-channel current events needs sufficient resolution of the signals from the background noise, which is accomplished by reasonable low-pass filtering. An increase of the recording bandwidth is therefore possible only if the background noise in the recording system is reduced. The background noise is determined in a complex manner by a number of individual noise sources. If these noise sources are uncorrelated, the standard deviation of the total noise is given by the square root of the summed squared standard deviations of the individual noise contributions, i.e., reduction of the largest noise contribution would cause the greatest reduction of the total noise. Hence, improved noise performance of patch-clamp amplifiers with integrated headstage technology may only be utilized if all additional noise contributions are reduced to a similar degree or, better, even more.


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Copyright information

© Springer Science+Business Media New York 1995

Authors and Affiliations

  • Klaus Benndorf
    • 1
  1. 1.Department of PhysiologyUniversity of CologneCologneGermany

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