regexp_replace: LF, CR, or tab

Hi!

I am trying to replace characters '\r', '\n', or '\t' with space character ' '. As an example, I want string "A\t\n\rB"
becomes"AB".  The following statement seems to be not working. What mistake have I made? 

TIA

CN
========

select regexp_replace(E'A\r\n\tB',E'[\r\n\t]',' ');
 regexp_replace
----------------
 A
         B
(1 row)