The amplitude response and gain flatness of the input selector is shown below. As you would expect from a passive preamp, the gain is completely flat and slightly below unity due to the load of the volume pot on the signal source.


More importantly, the left-to-right channel crosstalk is very low as shown below. Note that the crosstalk is the inverse of the channel separation. Thus, the channel separation of the Input Selector is very high.

In addition to providing good separation between left and right channel, the Input Selector must also have good isolation between inputs. Otherwise the signal from an unselected source can leak through to the output. The measurement below shows the leakage from an unselected channel. As you can see, the leakage is very, very low. In fact, it is below the noise floor of the APx525 audio analyzer.
