Re: [Harp-L] The shapes of the covers

[David Payne <dave@xxxxxxxxxxxxxxxxxxxxxx>]

Â
Hey Vern, you âskeptical old curmudgeon!â 
Here's my take:
A harmonica will sound best with no covers at all. If you could only play it like that. 
With the exception of materials used, diatonics really haven't changed in over 100 years. The coverplate was invented to keep these long German moustache hairs out of the reeds when they played âDu Liegst Mir Herzen,â etc.. It was not to improve tone, although manfacturers worked on coverplate design to alter tone and volume, the two greatest examples were in the 1890s with Richard Seydel Sr. and the Seydel Bandmaster and Jacob Hohner with the Mouse ear Marine Band.
For a coverplate to have any real acoustic qualities, I imagine the chamber inside the coverplates would need to be about the size of a mandolin's body. What the coverplates do is muffle sound, and direct it so you can do vibratos and stuff. The main differences between coverplates would be in how and how much they muffle that sound. 
When Joe puts tape inside, the muffling is increased. So the differences between coverplates would be how much of that sound they muffle.
Vern, I'm with you that the harmonica coverplates do not work like the resonant chamber of a mandolin or guitar. But if you would please, explain to me what's going on in the video below when I cover the side vents on the prewar Seydel Bandmaster and the prewar Marine Band and there is this extremely obvious difference in the sound that's even clear when recorded on a digital camera. If you could explain that to my satisfaction, I'd be forever grateful. 



http://www.youtube.com/watch?v=uVu2TY68vbs
Dave
____________________

Dave Payne Sr. 
Elk River Harmonicas
www.elkriverharmonicas.com


----- Original Message ----
From: Vern Smith <jevern@xxxxxxx>
To: harp-l@xxxxxxxxxx
Sent: Friday, July 11, 2008 12:45:45 PM
Subject: Re: [Harp-L] The shapes of the covers

As harp-l's self-appointed, skeptical old curmudgeon, I hear the call of 
duty to bust another myth.

There is nothing about the acoustics of the harmonica that suggests that the 
covers play any role in the generation of the sound. The covers define the 
shape of the sound passage from the reeds to your ear. They might 
conceivably affect the coupling of the sound to the outside air as does the 
bell of a horn.. They might have a slight effect on loudness but not tone.

Because the human ear has a logarithmic response, small changes of sound 
energy are imperceptible.

I predict that in a blind comparison of machine-blown diatonics, listeners 
could not distinguish between groups of harps with covers and no covers 
(much less covers having minor design differences) by the sound alone. I 
suggest that any effort to achieve nuances of tone (warm, bright, etc.) by 
means of cover design is wasted.

Vern
Visit my harmonica website www.Hands-Free-Chromatic.7p.com

----- Original Message ----- 
From: "John F. Potts" <hvyj@xxxxxxx>
To: <lavoie@xxxxxxxxx>
Cc: <harp-l@xxxxxxxxxx>
Sent: Friday, July 11, 2008 2:57 AM
Subject: [Harp-L] The shapes of the covers


> Mark,
> What effect do vented covers (Big River, Marine Band) have as compared to 
> unvented covers (Mesterklasse, Golden Melody, Promaster)Â or very slightly 
> vented vented covers (Proharp)?
> JP
> _______________________________________________
> Harp-L is sponsored by SPAH, http://www.spah.org
> Harp-L@xxxxxxxxxx
> http://harp-l.org/mailman/listinfo/harp-l 


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