<p>There are a few things that point to why the <a href="http://www.youtube.com/watch?v=OUvlamJN3nM" rel="nofollow noreferrer">A in C minor tone</a> was chosen for this purpose.</p>
<h1>The Bell</h1>
<p>The first is in a subset of the lyrics from <em>In the Land of Twilight Under the Moon</em>. This part of the lyrics seems to reference A in C minor in that this tone, which is unique enough to be commonly used for tuning instruments (via tuning fork), is sometimes known for its similar sound to a bell (as in the <a href="http://www.youtube.com/watch?v=BN987vxtiuQ" rel="nofollow noreferrer">video you linked</a>).</p>
<blockquote>
<p>High and loud, the sound of your bell of the<br />
Twilight... ringing...<br />
All alone, it rings and echoes in twilight</p>
<p>  — <a href="http://dothack.wikia.com/wiki/SIGN_Original_Soundtrack_2#In_The_Land_of_Twilight_Under_The_Moon" rel="nofollow noreferrer">SIGN Original Soundtrack 2, <em>.hack</em> Wiki</a></p>
</blockquote>
<h1>Liminality</h1>
<p>The second is somewhat more convincing; the sound may be considered a manifestation of Liminality. The game can, of course, make contact with the human mind, and the tone itself is subliminal. This means it was probably programmed in by Harald, being key to this mental contact, much like hypnosis (which uses specific types of lights for maximum effect).</p>
<p>In reality, there is nothing special about the properties of A in C minor (with the exception of its ability to be easily differentiated from other notes); it is heard at approximately 440Hz, though its range extends as low as 435Hz. However, in the <a href="http://en.wikipedia.org/wiki/.hack//Liminality" rel="nofollow noreferrer"><em>.hack//Liminality</em> OVA</a>, it is (incorrectly) stated that the tone is the highest note a human can hear. In the <em>.hack</em> universe, most people are unable to hear this tone, but Mai can.</p>
<h1>Overall</h1>
<p>It seems that the note itself was chosen for its uniqueness (especially in that it is easy for the human ear to hear), as well as its faux property of being the highest note humans can hear. The A in C minor tone itself is not exceptionally notable outside of the <em>.hack</em> universe.</p>
<p>The note itself is also the first letter in the musical scale and its use is somewhat akin to <a href="http://matrix.wikia.com/wiki/D%C3%A9j%C3%A0_vu" rel="nofollow noreferrer">déjà vu in <em>The Matrix</em></a>, though these are not as likely to be related.</p>

CC BY-SA 3.0
2013-05-18T18:42:44.357Z
2013-05-18T18:42:44.357Z
2020-06-17T09:17:53.303Z
Cattua
<p>Mai Minase first notices this in <em>.hack//Liminality</em> when she and Tomonari Kasumi are attacked by the First Phase, Skeith.</p>

<p>The "A in C major" tone (ハ長調ラ音) seems to recur whenever some strange event happened "The World" and it's subsequent iterations, like in "The World R:2," like when <a href="https://www.youtube.com/watch?v=M-SYkGvB7RI#t=86s" rel="nofollow">Azure Kite appeared</a>, the appearance of one of <a href="http://dothack.wikia.com/wiki/Category%3aPhases" rel="nofollow">the Phases</a>, or activation of <a href="http://dothack.wikia.com/wiki/Avatar_%28Phases%29" rel="nofollow">an Avatar</a>. </p>

<p>Why does this tone play during these events in both the anime series and the games?</p>

<p><a href="http://www.youtube.com/watch?v=BN987vxtiuQ" rel="nofollow">http://www.youtube.com/watch?v=BN987vxtiuQ</a></p>

CC BY-SA 3.0
2013-05-12T02:03:33.820Z
Didn't you just explain the significance? It plays when there is a strange event.
atlantiza
CC BY-SA 3.0
2013-05-12T02:05:23.457Z
But why does it play during strange events? Why "A in the fifth octave" of all things?
кяαzєя
CC BY-SA 3.0
2013-05-12T02:09:54.813Z
Then I think you should change your question to "Why does the A in C major tone occur whenever..." since you already know the significance.
atlantiza
CC BY-SA 3.0
2013-05-12T02:17:50.603Z
ok I'll change the context.
кяαzєя
CC BY-SA 3.0
2013-05-13T00:21:52.070Z
Er... How should this question be answered? With a research on how the frequency causes some sort of psychological effect on the viewer?
nhahtdh
CC BY-SA 3.0
2013-05-13T01:16:50.193Z
@nhahtdh Anyway you wish, as long as you can explain why this particular tone was chosen,
кяαzєя
CC BY-SA 3.0
2013-05-14T03:16:49.940Z
I have a sneaking suspicion that there was no reason...
atlantiza
Why does the "A in C major" tone play whenever a strange event occurs in The World?
# Why does the "A in C major" tone play whenever a strange event occurs in The World?
Posted by: username_0 on 2013-05-12
Mai Minase first notices this in *.hack//Liminality* when she and Tomonari Kasumi are attacked by the First Phase, Skeith.

The "A in C major" tone (ハ長調ラ音) seems to recur whenever some strange event happened "The World" and it's subsequent iterations, like in "The World R:2," like when [Azure Kite appeared](https://www.youtube.com/watch?v=M-SYkGvB7RI#t=86s), the appearance of one of [the Phases](http://dothack.wikia.com/wiki/Category%3aPhases), or activation of [an Avatar](http://dothack.wikia.com/wiki/Avatar_%28Phases%29).

Why does this tone play during these events in both the anime series and the games?

<http://www.youtube.com/watch?v=BN987vxtiuQ>
> **Comments:**
> **username_1**: Didn't you just explain the significance? It plays when there is a strange event.  
> **username_0**: But why does it play during strange events? Why "A in the fifth octave" of all things?  
> **username_1**: Then I think you should change your question to "Why does the A in C major tone occur whenever..." since you already know the significance.  
> **username_0**: ok I'll change the context.  
> **username_2**: Er... How should this question be answered? With a research on how the frequency causes some sort of psychological effect on the viewer?  
> **username_0**: @nhahtdh Anyway you wish, as long as you can explain why this particular tone was chosen,  
> **username_1**: I have a sneaking suspicion that there was no reason...  
---
## 1 answers
### Answer by username_3 on 2013-05-18. Score: 3 | Accepted answer
There are a few things that point to why the [A in C minor tone](http://www.youtube.com/watch?v=OUvlamJN3nM) was chosen for this purpose.

# The Bell

The first is in a subset of the lyrics from *In the Land of Twilight Under the Moon*. This part of the lyrics seems to reference A in C minor in that this tone, which is unique enough to be commonly used for tuning instruments (via tuning fork), is sometimes known for its similar sound to a bell (as in the [video you linked](http://www.youtube.com/watch?v=BN987vxtiuQ)).

> High and loud, the sound of your bell of the  
> Twilight... ringing...  
> All alone, it rings and echoes in twilight
>
>   — [SIGN Original Soundtrack 2, *.hack* Wiki](http://dothack.wikia.com/wiki/SIGN_Original_Soundtrack_2#In_The_Land_of_Twilight_Under_The_Moon)

# Liminality

The second is somewhat more convincing; the sound may be considered a manifestation of Liminality. The game can, of course, make contact with the human mind, and the tone itself is subliminal. This means it was probably programmed in by Harald, being key to this mental contact, much like hypnosis (which uses specific types of lights for maximum effect).

In reality, there is nothing special about the properties of A in C minor (with the exception of its ability to be easily differentiated from other notes); it is heard at approximately 440Hz, though its range extends as low as 435Hz. However, in the [*.hack//Liminality* OVA](http://en.wikipedia.org/wiki/.hack//Liminality), it is (incorrectly) stated that the tone is the highest note a human can hear. In the *.hack* universe, most people are unable to hear this tone, but Mai can.

# Overall

It seems that the note itself was chosen for its uniqueness (especially in that it is easy for the human ear to hear), as well as its faux property of being the highest note humans can hear. The A in C minor tone itself is not exceptionally notable outside of the *.hack* universe.

The note itself is also the first letter in the musical scale and its use is somewhat akin to [déjà vu in *The Matrix*](http://matrix.wikia.com/wiki/D%C3%A9j%C3%A0_vu), though these are not as likely to be related.
---
