Agilent U8903A VEE Sample Program for Creating Your Own Notch Filter - Application Note Notch Filter Design free download

File name U8903A VEE Sample Program for Creating Your Own Notch Filter - Application Note Notch_Filter_Design_

Three Easy Steps to Create Your Own Notch Filter for the Agilent U8903A audio analyzer using the Agilent VEE software Application Note Introduction This application note assists you in creating your own customized notch filter for your audio analysis by using a VEE program. The VEE program will help you to create an FIR digital filter to be used in your U8903A. You can have the option of installing the notch filter permanently into your U8903A nonvolatile memory or of recalling the filter when it is needed from a PC through IO connectivity. Back to Basics What is an audio filter? Digital or analog filter? Any medium that an audio signal An analog filter is any filter that operates on continuous-time signals. In other passes through, whatever its form, respects, it is just like a digital filter. Analog filters were used successfully for can be regarded as a filter. Filters are decades before digital filters come along. Although analog filters are excellent usually used to discriminate between in some aspects, especially in cost, they do have some serious drawbacks. One a frequency or a band of frequencies of the drawbacks of analog filters is the non-linear phase characteristics. This from a given signal, which is normally does not affect most of the common applications, but it is heavily involved in a mixture of both desired and applications like telecommunications and voice processing. Another drawback undesired signals. The undesired in analog filters is the lack of sharpness at the cut-off frequency. It is possible portion of the signal commonly comes to increase roll-off rate by cascading filter stages, but this will increase the cost from noise sources such as power and complexity of the system. On the other hand, it is possible to achieve all line hum, which are not required for a these characteristics fairly by using a digital filter. particular application. A digital filter is just a filter that operates on digital signals, such as sound However, we do not usually think represented inside a computer. It is a computation, which takes one sequence of something as a filter unless it of numbers (the input signal) and produces a new sequence of numbers (the can modify sound in some way. filtered output signal). The filters mentioned are not for digital signals only as For example, a speaker wire is not they can be operated on signals that are not digital as well. It is important to considered a filter, but the speaker realize that a digital filter can do anything that a real-world filter can do. That is. The tone control circuit in an is, all th