Can the S-corp contribute only to a SEP account or can there be a contribution to a privately set up/owned 401 K ? Owner has W2 Salary from Scorp / with 25% towards SEP?

Can the S-corp contribute only to a SEP account or can there be a contribution to a privately set up/owned 401 K / Roth account. 

Currently S-corp contributes only to Owners SEP account .

(Owner who is a employee of the Scorp receives a yearly salary via W2).   The current contribution to SEP is 25% of Salary