[Harp-L] Re: Importance of Close Reed Tolerances (was Manji welded reeds?)



Hi Ken,

I was looking at reed clearance from a total-leakage point of view. As a chromatic-only player, I admit to a vast ignorance about overbends and overdraws. They are all button-pushes to me! I accept that the closer clearances are important to advanced diatonic players.

Do you have any idea about the quantitative values of the clearances. Measurements that I have made indicate clearances of about .0015" to .0018" are common in production harps. What clearance values provide superior overblow/overdraw performances? As the clearances approach zero, what problems appear?

Thank you not only for your corrections & comments but also for your lucid explanation.

If you are attending SPAH, would you enlighten me further and indulge some more questions over a beer?

Vern


----- Original Message ----- From: "Mojo Red" <harplicks@xxxxxxxxx>
To: "Vern Smith" <jevern@xxxxxxx>
Cc: "Harp -l" <harp-l@xxxxxxxxxx>; "Michael Peloquin" <peloquinharp@xxxxxxxxxxx>; "Chris Michaleck" <groovygypsy@xxxxxxxxx>
Sent: Monday, August 10, 2009 2:38 PM
Subject: Importance of Close Reed Tolerances (was Manji welded reeds?)



Hi Vern,


You said something in your Manji post that I disagree with, and thought it bore more discussion. You said: "Better alignment and closer tolerances are real but marginal advantages to the user..."

I think good reed alignment and close tolerances are hugely important, and not at all "marginal" to the user, particularly if the user happens to use overbends... and even more important to an individual whose overbending technique is not perfect.

In fact, from my experience (as an imperfect overbender), next to proper gapping, good close reed slot tolerance is one of the most important advantages of a well set up harp. And it is VERY difficult to achieve close reed-to-reed-slot tolerances if the reed is not first properly aligned.

As you may already know, the ability to achieve a stable and repeatable overblow depends on the player's ability to quickly and completely close or choke off the blow reed in order to get the overbend to sound on the draw reed. Similarly, the ability to achieve a stable and repeatable overdraw depends on the player's ability to completely close or choke off the draw reed in order to get the overbend to sound on the blow reed.

Closer reed-to-reed-slot tolerances, in combination with a well gapped reed are the main factors that allow easier overbending. A well gapped reed improves overbending performance, but adding good close reed slot tolerances improves that performance by another factor entirely, particularly if the reed's profile has a slight arc that allows it to sit a little deeper into the slot.

In addition, close tolerances (IMO) allows for a a faster, louder and more responsive harp requiring less effort or breath-force from the player.

Now, admittedly, these advantages may be "marginal" to a beginning or novice player, but for serious players, I believe that close reed tolerances are a main hallmark of a great or well set-up harp.

I'm now wondering what other overblow players opinions are on this subject. Peloquin? Michaleck? Others? Comments?

Harpin' in Colorado,
--Ken M.

TeraBlu Band on My Space
http://www.myspace.com/terablu



----- Original Message ----
From: Vern Smith <jevern@xxxxxxx>
To: Michael Peloquin <peloquinharp@xxxxxxxxxxx>; Harp -l <harp-l@xxxxxxxxxx>
Sent: Monday, August 10, 2009 1:56:39 PM
Subject: Re: [Harp-L] Manji welded reeds?



----- Original Message ----- From: "Michael Peloquin" <peloquinharp@xxxxxxxxxxx>
To: "Harp -l" <harp-l@xxxxxxxxxx>
Sent: Monday, August 10, 2009 11:55 AM
Subject: RE: [Harp-L] Manji welded reeds?


From: tusker23@xxxxxxxxxxx
I'm a relative newbie to harp-playing and I know it's probably a dumb question, but.......if welded reeds are such a tremendous improvement over rivetted reeds, wouldn't replacing a welded reed with a screw-fastened reed result in a poorer quality harmonica?

Good question.


If not, then why not use all screw-fastened or bolted reeds in the first place, rather than welded reeds?

Spot-welding is much more amenable to an automated assembly process than rivets or screws. (See those videos on assembly of automobile bodies.) One suspects that this is the most important reason for choosing spot-welding. Better alignment and closer tolerances are real but marginal advantages to the user...
<Snip>









This archive was generated by a fusion of Pipermail 0.09 (Mailman edition) and MHonArc 2.6.8.