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Carl Martin Contour Boost Effects Pedal Low High Pass Filter [Contour] - $215.00 : GuitarBassPro!, Bass Guitars Amplifiers Pro Audio and accessories
![NPD - Broughton Low + High Pass Filter. Does a great job of cleaning up muddy low end and hissy high end frequencies I don't want. Just the creamy middle! : r/BassGuitar NPD - Broughton Low + High Pass Filter. Does a great job of cleaning up muddy low end and hissy high end frequencies I don't want. Just the creamy middle! : r/BassGuitar](https://external-preview.redd.it/z3AAbc7GLSWlmUKQSdtc7fPpjf8YIFLs0vtT9s85h3U.jpg?width=640&crop=smart&auto=webp&s=7f3e54ef139c7145ffe4f7141e14f603f750b146)
NPD - Broughton Low + High Pass Filter. Does a great job of cleaning up muddy low end and hissy high end frequencies I don't want. Just the creamy middle! : r/BassGuitar
![circuit design - Standard ways to make a variable low pass filter - Electrical Engineering Stack Exchange circuit design - Standard ways to make a variable low pass filter - Electrical Engineering Stack Exchange](https://i.stack.imgur.com/11bIv.png)