.set for Synthdef via MIDI cc message

Hi, I am trying to control a LowPassFilter argument for a SynthDef via a cc MidiDef, but I cannot get it right. Seems to me I cannot use the .set function for Synth in that way; ~oa is the synth the case below:

MIDIdef.cc(\dataentry,{|val,chan,src|[val,chan,src].postln; ~oa.set(\cutt,val.linlin(1,127,110,880))},7);

solved it! just had to connect the variable

MIDIdef.cc(\dataentry,{|val,chan,src|[val,chan,src].postln; a.set(\cutt,val.linlin(1,127,110,880))},7);
(
MIDIdef.noteOn(\synhtone,{|val,num,chan,src|[val,num,chan,src].postln;
	if( num==36,{a=Synth.new(\oa,[\n,13.neg])});