This advice-column-style blog for SLPs was authored by Pam Marshalla from 2006 to 2015, the archives of which can be explored here. Use the extensive keywords list found in the right-hand column (on mobile: at the bottom of the page) to browse specific topics, or use the search feature to locate specific words or phrases throughout the entire blog.
Q: My client started with a frontal lisp. Now he is now producing a “Whistling S.” How do I correct this?
A whistling S usually is an S that is being made in just the right place that whistling occurs. Simply have your client begin to move his tongue-tip higher or lower, slightly more forward or back, or slightly more to the left or right as he prolongs his S. You are searching for the place that works to alleviate the whistle and achieve the best sound quality on S for him. That is all a matter of trial and error. You are training his ear to hear the fine differences that occur in the sound quality as he moves his tongue-tip by millimeters at a time in one direction and then another.