how do I fix this so that I get all the signals while still using the send function?

also, please be kind. this is me just starting out and experimenting.

http://www.pdpatchrepo.info/hurleur/volumepitchratio2.pd

The "multiply defined" error is referring to the multiple [s~ dac] objects you have. With [send~]/[receive~] pairs, you are only allowed to have one [send~] with the same name, but you can have multiple [receive~]s with the same name. What you want here is [throw~]/[catch~]. With these, you can only have one [catch~], but multiple [throw~]s.

I'm not sure what the reasoning is for those being separate, but my guess is it makes it easier for Pd to execute the DSP chain in the right order.

awesome! I'm loving pd and I love the helpful community! so psyched!!