[Harp-L] overblow begginner question

[drori hammer <drori_hammer@xxxxxxxxx>]

Hi -
I am a fairly experienced blues harp player and I am trying to teach myself to overblow, with the help of the various websites (if any one can suggest more of these-thanks!) - so far without great results.
My question is : is it absolutely neccessary to have your harp specifically "set up" for overblowing, or can I use my regular harps . What I am trying to understand is if it`s just my technique that`s wrong or if I need to alter my harps. ( I might add that I am clueless as to all matters of tweaking and repairing harps)
The harps I am using at the moment are mostly Hering vintage 1923s and some Hohner MBs and Big River`s. Is it possible to OB on these without major tweaking?
Thanks for any tips
Hammer
 

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