[Harp-L] The overblow wars and the articulation of the overblow

["Tinus Koorn" <tinus@xxxxxxx>]

I enjoyed reading Ben's fine post on overblowing the importance of a
technical aspect of playing and I felt a little ashamed because I know I did
in fact start working on B&S after Rick's post. :)

Recording B&S I suddenly became very aware of the difference in articulation
between overblows and normal notes.

I would very much like to discuss these differences.

> I just don't
> understand this whole "OBs are Evil" / "No they're not" debate.

So if I could ask all of you to leave the "you shouldn't play them" and the
"it'll never work" trains of thought for a minute to concentrate on
 the sound of both the overblow and the normal note I would be very
thankfull.

I know that there is a difference in timbre that is caused by 
the fundamental difference in the way the reed moves in relation to the
plate.

An opening reed will produce a different waveform than a closing reed.
However I have 2 questions about this

1. do you think that this difference becomes relatively smaller if the
player plays at a higher volume?

I think that there might be a chance that as the reeds amplitude becomes
bigger the effect of the inherent differences will be smaller. I intend to
investigate this, but I am curious to hear peoples opinion.

2. appart from the timbre difference, what difference dou you hear in the
articulation of the notes?

I think that there is a very clear difference between a normal note and and
overblown note when they are articulated with the tip of the tongue. Unlike
the difference in timbre I think that the difference in articulation might
be overcome and in order to do this I think that a good understanding of
what the difference actually is would be very helpful.

I am also planning to investigate the differences in articulation and their
effects, but I would like to gather opinions before I do that so I don't
miss anything when I look for them.

At the moment I think I hear this:
When a normal note is articulated with the tip of the tongue (like playing
the note with a "tweeee" articulation) I first hear a small dip in frequence
that sort of resolves to the reeds eigen frequency combined with stronger
sounding higher harmonics.
On the overblow this dip doesn't occur naturally (but could be played
consciously) and the presence of the higher harmonics doesn't happen,
possibly because they aren't there.

The other difference that seems very clear to me is that of the release.
When a normal note is released it very gently dies out, the overblow is much
more eager to stop sounding. Possibly this difference could also be changed
by learning to let the overblows die out in the same way that a normal note
does.

I would very much like to hear you opinions so I can start investigating
these differences with as good an idea of what is going on as possible.

If anybody has any suggestions for audio analyses software tools that would
be greatly appreciated too.

Tinus
http://www.tenhole.com
http://www.overblow.com