[maxmsp] signal process selected pitches

I'm trying to pass selected pitches to msp audio processing. So for example all 'C' notes are passed to a delay. Using selector~ or gate~ in the signal chain sort of works but in addition to a click when they are switched they shut down the signal path.

So be fore I write something to trigger a quick fadeout and fadein I thought I would see what users in the forum may suggest.

When searching the object DB I saw that the ircam jimmies had something called mute1~ that looked close to what I'm trying to do but didn't see anything else.

Appreciate any and all suggestions.

Chris