ClockSpeed English

Overview ClockSpeed

The App ClockSpeed records the ticking of your watch or clock, and analyses the sound to find the precision and accuracy of it.

The sound is recorded lossless with a sampling rate of 192kHz, which gives it a precision of about a ½ second deviation per day, with a recording of just about 1 minute.

You can import the sound recorded with another tool, e.g. the Apple Voice Memos App, which can record maximal with 48kHz, which reduces the accuracy of the App result to a deviation of about 2s per day.

The App works with some assumptions:

1) The loudest noise on your recording needs to be the ticking. Side noises are OK as long they are quieter. Passing cars or chirping birds can be very loud, so do not expect a good result with a poor recording. Some single short noise peak can be filtered out by the App.

2) Listen to your recording – can you hear the ticking? If not, the result might be inaccurate. Watch the provided picture of the sound, you usually can see side noises and disturbances.

3) You know how fast the clock should be, and how many ticks are expected per second. Imagine a pendular clock, which ticks once per second, and your wrist watch ticks maybe 8 times a second. You need to select the correct speed in settings, a wrong choice leads to a wrong result.

4) Each tick sounds identical, but in reality, they are not identical, therefore the measure is not perfect, but still very good. Do not try to verify the App with a ticking quartz clock, because that type of clocks has big differences in the single ticks. The balance wheel of a mechanical watch creates much more constant noises as a quartz clock with its plastic gears. Anyway, expect small variations of the result with different recordings, even if you do them just one after the other.

Audio Page

The Audio page gives you the following options:

• Record an audio file (the noise of a clock)

• Play a recorded or imported audio file

• Import a recorded audio file

• Export a recorded audio file

• Analyse an audio file

• Save the analysis result to your collection

In 4 frames you see the following information:

• Information about the current audio file

• A visual wave of the current audio file

• Some current settings

• The result of an analysis

The Functions: (the buttons from left to right):

Record: This function starts the recording of an audio file. It is recommended to hold the microphone very close to the clock or watch. To record the noise of a wrist watch, place the watch flat on a table and hold the iPhone from the top and press it slightly onto the watch. Make sure not to move during the recording session, and make sure you are in a very quiet environment. The recording stops after the set time or when you tab the button again.

Play: This function plays the current audio file. As the audio might be very quiet, make sure to maximise your volume.

Import: Import an audio file from your device storage or from your iCloud.

Export: Export your audio file to your device storage or your iCloud. Note, if you record a 120s audio file, it will have about 50MB due to its high-resolution format.

Analyse: This is the main purpose of this app. For a long audio file, it may take up to about 5s to run. The result is shown in the result frame.

Save: This saves your current result to your collection for later reference. Note: It does not save your audio file, so in case you want to keep your audio file, export and save it separately.

The Result: Only the full version shows the result very detailed, while the free version shows only a rough accuracy. When you save the result to your collection, the detailed result is saved, but only the full version shows it.

Collection Page

The Collection shows all your saved results. A result shows:

• The graph of the audio file

• The name you gave your collection item

• The time stamp of your result

• The sampling rate of your audio file (sr: in kHz)

• The ticks/s used for the analysis

• The deviation per day (dev/day) in seconds (negative means the clock was slow)

• The number of found samples during the analysis

• The quality of the result
  (calculated as percentage of how many samples found of how many possible samples)

• The cutoff value start/end (s/e) in seconds

• The duration of the audio file

You can delete an entry by swiping it to the left.

Settings Page

The possible settings are:

Reset all values: 

• sets the ticks/s to 8

• sets the record duration to 45s (full version) / 15s (free version)

• sets the cutoff start to 1s and cutoff end to 0s

Ticks/s:

• choose the ticks/s between 1 and 10 – you can see here typical use cases

• the free version only supports 8 ticks/s

Record duration in seconds:

• choose between 15s and 120s. For a good result about 45-60s are a good choice

• the free version only supports 15s

Cutoff start / end seconds:

• to suppress any noises at the start or end, chose up to 10s to cutoff
  (this does not cutoff the audio file, it just ignores these parts during the analysis)

• The default value for the start is 1s, this makes sense as the audio file usually has a lower volume during the first second.

On this page you can buy the full version of the App, or in case you re-installed it after purchase, you can restore your purchase.