Davison left Town last week, just one-year into his contract. The veteran agreed to terminate his contract with manager Russell Slade and chairman Peter Furneaux.
Davison will link up with the Layer Road outfit as first choice 'keeper following the departures of Simon Brown and Richard McKinney to Hibs and Walsall respectively.
Part of Davison's duties will also see a coaching role with the Essex clubs younger goalkeepers.