[Harp-L] enforcing overtones / harmonics

[Ralf Kapp <truebe_zitrone-aroma@xxxxxxxx>]

Hi all,

the recent jaw harp thread made me explore a phenomenon i stumbled upon 
by accident a few weeks ago. I was experimenting with different shapes 
of the oral cavity when suddenly an additional, much higher note popped 
out. The new note seemed to be a fifth but was very quiet. Knowing I 
happened to produce or enforce an overtone I postponed the exploration 
to a future date due to lack of time.

Welcome in the future! The last two days I practiced that effect a lot 
and was able to enforce the overtones to a volume clearly audible with 
solo harp but too quiet to be heard with other instruments making all 
that kind of noise commonly known as music. So I skipped my initial idea 
to use the original note from the harmonica as a drone and play some 
melody using harmonics. But this fifth and some other neat intervals 
strongly remind me of mixture registers in church organs - which is no 
big surprise as they do the same thing.

I tried pucker, u-block and toungue block, pucker being my main 
embouchure and TB my weakest. Using a deep pucker I am able to produce 
the most harmonics, using u-block I get the most volume and with TB I 
find again that my toungue needs a lot more training...

The effect is greatest with soft to moderate breathing and I was able to 
reinforce it a bit trying to get in resonance with the new notes. But it 
seems that resonance thing works best for low frequencies so the the 
much higher sounding harmonics still are lacking volume.

I haven't tried it amplified yet. Maybe the harmonics produced by my 
little class A tube amp will reinforce the effect a little further, but 
my hopes are low. Another approach will be using a vocal mic and a 
highpass or bandpass filter but I assume it will be quite tricky to set 
up and will be limited to only a narrow frequency range.

Sooo, finally, has anyone on the L managed to enforce the harmonics 
acoustically to an extent that makes them usable as a mixture register 
effect in an (acoutic) band environment? Are there any possibilities to 
enforce higher notes through resonance? What techniques do other wind 
instruments use and are they applicable to harp? Throat singers? Opera? 
How do you acoustically mute low frequencies? Lots of questions, I know, 
but I also know there are a lot of multitalented wizards out there.

Thanks in advance,
Grüßle
Ralf