Being hand made every one is different and has its own personality. These are the only calls I make nowdays with a completely hand made toneboard everytime...and its a bitch sometimes. I do it old school. No jig or anything...just using my "eyecrometer".
Toneboard length, air channel width, toneboard height, curvature and reed shape all affect how it plays. These howlers are not meant for big deep howls...but to do a few of the most usefull things. ...high to medium pitch howls, pup talk, some barks and ki yis...those are what are important to me in a howler. ..and a howler..either open reed or diaphragm...is a must have for me....they are that useful. On this one, I didn't have the board slope how it needed to be...I took off to much and it wasnt how I like it but it was ok really. A deeper pitched howler can have a wider air channel and/or a longer or bigger ID barrel. Some of that causes its own problems.
Some of them I do "detune' the reed a bit..depending on how the toneboard came out..putting the tip of the reed just short of the end of the air channel sort of like a goose call looks..kind of counter intuitive to how an open reed is usually tuned..but some of them are more responsive or less sensitive that way . It works for me anyways.
The rasp for barks and front end of raspy howls and ki yis etc is done by quickly covering the relief hole partially with your bottom lip...not blocking it off completely but just brushing across it real fast...or even just getting close to it.. It creates the instant backpressure to get the rasp. Hard to explain and not intuitive to most people maybe..but once you get used to it it will be second nature.
The wavering is a matter of air control really and moving just slightly up or down the reed. I dont do big sliding howls...these toneboards are short on purpose...1) so you can reach the relief hole easily and 2) so you dont have to go far either way on the reed to do stuff. To long a toneboard and things get useless and more difficult imo....like locking down etc. Also the angle you hold it makes a difference as well.
More on the rasp/relief hole thing...you can accomplish the same thing essentially by putting a hole somewhere in the call barrel, toneboard wedge or somewhere else to relieve backpressure..but those arent as quick to use as how I have it. Again, for me.
Sorry for the rambling : )
EDIT: Maybe I misunderstood? Wavering...the quick wavering on the tailend of some of the howls is me just bouncing my top teeth or lip onto the reed.
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