In general, the subject matter described in this disclosure can be embodied in methods, systems, and program products for changing the manner in which an input signal is filtered based on a characteristic of an electronic test instrument. The method includes receiving, by the electronic test instrument, user input that modifies a characteristic of a channel of the electronic test instrument, and as a result changing the electronic test instrument from having the first digital filtering configuration to having a second digital filtering configuration, the first digital filtering configuration specifying that all or a majority of digital filtering occurs after the acquisition memory in the channel and the second digital filtering configuration specifying that all or a majority of digital filtering occurs before the acquisition memory in the channel.