[CAUT] Birkett videos online

[Ed Sutton]

This is what Weinreich's often-cited paper discusses.
Jim Ellis (PTJournal, Fall 1982) states that piano unisons will tend to 
couple in out-of-phase relationship, as we see in the video.
If I understand Capleton correctly, all unisons couple when they are within 
some critical frequency band (and this band will vary for different 
partials), and, once two string of a unison have coupled, the third string 
will be drawn into coupling at a greater distance than that between the 
first two. This may be what we are seeing in the video of C64, where two 
strings seem to move in phase and the third is parallel, out of phase. They 
all seem in phase at the start, them the treble-most string begins to 
wander. Once it is exactly out of phase, it appears to "lock in."

Ed S.


> Adkins, Richard wrote:
>> Is it me, or does that left string of  trichord  get out of phase as
>> the clip progresses in this clip?
>