Question

17 multiple choice 1 point if you start with a note with a frequency of 660 hz, what frequency is two octaves lower than this frequency? 330 hz 2640 hz 165 hz 1980 hz 1320 hz 18 multiple choice 1 point the note that is e above middle c has a frequency of approximately 329.6. what is the frequency of the next lowest semitone? 311.102 hz 261.607 hz 293.642 hz 277.162 hz 246.925 hz

Explanation:

Step1: Recall octave - frequency relation

Each octave lower halves the frequency.

Step2: Calculate one - octave lower

For a frequency of 660 Hz, one octave lower is $\frac{660}{2}=330$ Hz.

Step3: Calculate two - octaves lower

Two octaves lower is $\frac{330}{2}=165$ Hz.

Step1: Recall semitone - frequency relation

The ratio of frequencies of two adjacent semitones is $2^{\frac{1}{12}}$. To find the lower semitone, we divide by $2^{\frac{1}{12}}$.

Step2: Calculate the lower - semitone frequency

Let the given frequency $f = 329.6$ Hz. The frequency of the next lowest semitone is $f_{lower}=\frac{329.6}{2^{\frac{1}{12}}}\approx311.102$ Hz.

Answer:

C. 165 Hz