Zooming in to see samples in an audio editor

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Quick Questions

Shade in the A or B circle for each question.

1. You record a short sound in Audacity and zoom in as far as you can. What do you see?

A Individual dots, and each dot is one sample

B A perfectly smooth curve with no dots

2. What does one dot on a zoomed-in waveform stand for?

A One whole second of the recording

B One measurement of the sound's volume at one moment

3. Which project rate gives more dots every second when you zoom in?

A 44100 Hz

B 8000 Hz

4. You zoom in on the same sound recorded at a high rate and at a low rate. How do the dots compare?

A The high rate has dots packed closer together

B The low rate has dots packed closer together

5. Why does a high sample rate draw the wave more smoothly?

A Each dot gets louder, which smooths the line

B More dots mean the shape of the wave is followed more closely

Match the Pairs

Draw a line connecting each item on the left to its match on the right.

Left column		Right column
1Zoom in until dots appear		AThe editor stores 44,100 sample dots for every second of sound, so the wave looks smooth.
2Project Rate: 44100 Hz		BProject Rate: 8000 Hz
3Record a short sound, then zoom in until you can see each sample dot		CRecord, then View > Zoom > Zoom In
4A low sample rate gives fewer dots per second, so the wave looks blocky		DA lower project rate gives fewer dots per second, not more. A higher rate gives more dots.
5Zoom out far to see each sample dot		EZooming out shows a longer stretch of sound and hides the dots. You must zoom in to see single samples.
6Lower project rate = more dots per second		FZooming far into a waveform in Audacity shows each sample as its own dot on the wave.

Definitions

Zoom in to samples

Fill in the Blanks

Complete each line of code by filling in the missing parts.

record(sound) ______(sound)

projectRate = _____

IF highRate _ lowRate THEN moreDots

dots = seconds _ sampleRate

FOR EACH sample IN track: drawDot(______)

Spot the Error

Shade in the letter of the line that contains an error.

Question 1

A rate == 44100

B dots_per_sec = rate

C print(dots_per_sec)

Question 2

A record_seconds = "3"

B rate = 8000

C total = record_seconds * rate

D print(total)

Question 3

A record(2)

B rate = 44100

C zoom_out("max")

D print("dots appear")

Question 4

A set_rate(8000)

B record(2)

C zoom_in("max")

D print("each dot = 1 second")

Question 5

A low = 8000

B high = 44100

C if high < low:

D print("high is smoother")

Answer Key

Zooming in to see samples in an audio editor

Section A: Quick Questions

A — Individual dots, and each dot is one sample

B — One measurement of the sound's volume at one moment

A — 44100 Hz

A — The high rate has dots packed closer together

B — More dots mean the shape of the wave is followed more closely

Section B: Match the Pairs

Zoom in until dots appear → Zooming far into a waveform in Audacity shows each sample as its own dot on the wave.

Project Rate: 44100 Hz → The editor stores 44,100 sample dots for every second of sound, so the wave looks smooth.

Record a short sound, then zoom in until you can see each sample dot → Record, then View > Zoom > Zoom In

A low sample rate gives fewer dots per second, so the wave looks blocky → Project Rate: 8000 Hz

Zoom out far to see each sample dot → Zooming out shows a longer stretch of sound and hides the dots. You must zoom in to see single samples.

Lower project rate = more dots per second → A lower project rate gives fewer dots per second, not more. A higher rate gives more dots.

Section C: Definitions

Zoom in to samples — Zooming far into a waveform in an audio editor like Audacity shows each sample as a dot. A higher project rate gives more dots every second, so the wave is drawn more smoothly.

Section D: Fill in the Blanks

record(sound)
zoomIn(sound)

projectRate = 44100

IF highRate > lowRate THEN moreDots

dots = seconds * sampleRate

FOR EACH sample IN track: drawDot(sample)

Section E: Spot the Error

A — A single = stores a value in the variable. == only compares two values. It should be rate = 44100.

A — The length of the recording must be a number so it can be multiplied by the rate to count the samples. "3" is text. It should be record_seconds = 3.

C — You must zoom IN to see the individual sample dots. Zooming out shows the whole wave. It should be zoom_in("max").

D — Each dot is one sample, which is one volume measurement. It is not a second of sound. It should say each dot = 1 sample.

C — 44100 is greater than 8000, so the higher rate should be the one tested. The condition should be if high > low: so the message prints.