sound, especially in the higher frequencies, as reproduced by equipment in common use at the time.  These imperfections included clicks and pops (from 78 rpm recordings), added noise (from AM radio broadcast static), hiss and harmonic distortion (from amplifier circuits), and non linear frequency response from primitive loudspeaker designs. If the sound was free of these problems, he reasoned, listeners would prefer full frequency reproduction.

In his experiment, he set up a room which was divided diagonally by a visually opaque but acoustically transparent screen. The screen incorporated a concealed low-pass acoustical filter having an upper frequency cutoff of 5000 Hz.  This filter could be opened or closed, allowing either the full range of frequencies to pass or the range only below 5000 Hz. At first, a small orchestraSocial Sharing

Tweet by Denise Batters, which she deleted, has led to calls for her resignation

Senator Denise Batters experienced a backlash on social media over what some have interpreted as a racist tweet about Liberal MP Omar Alghabra. (Sean Kilpatrick/Canadian Press)

Conservative Sen. Denise Batters apologized to Liberal MP Omar Alghabra today for her choice of words in what some interpreted as a racist tweet.

"My intent was to suggest Mr. Alghabra's experience living in Saudi Arabia would give him unique insight about the difficult situation in which Canada and KSA find themselves," Batters wrote today in a follow-up to an earlier tweet questioning why Alghabra appeared on CBC's Power and Politics to address the diplomatic conflict with the Kingdom of Saudi Arabia.

"I absolutely did not intend to suggest that Mr.