Re: [Harp-L] Reed slot needs to be shortened

[Zombor Kovacs <zrkovacs@xxxxxxxxx>]

I get it. Well, I can't say anything else than have fun with shortening the 
slots then :-)

Are the slots stamped out, or milled?





________________________________
From: Doug H <dough.harpl@xxxxxxxxx>
To: Zombor Kovacs <zrkovacs@xxxxxxxxx>; Harp L Harp L <harp-l@xxxxxxxxxx>
Sent: Sun, October 31, 2010 1:07:16 AM
Subject: Re: [Harp-L] Reed slot needs to be shortened

 
I agree that in a typical situation it would make  more sense to change the reed 
rather than the slot, but this is not a typical  situation.
 
These reed plates are for a prototype that I am  building of an experimental 
harmonica.  It has a full set of blow reeds and  of draw reeds over 3 octaves, 
installed on four reed plates.  It's sort of  a hybrid between a chromatic and a 
Harmonetta.  (I will have a website up to speed in a few weeks to explain what I  
am doing.)
 
The slots are sized to take the reeds of the  correct pitch from the CX-12.  I 
decided to use CX-12 reeds because they  are easily available and come in 
various keys, and I will be using screws to  attach them.  A major reason why I 
want to  have the slots fixed is so that later, as I experiment, I can easily 
swap out  the reeds for a set in a different key, or if someone else has the 
thing they  could make the swap without having to deal with the one odd-ball  
reed.
 
It is only 1 slot that I have to fix per harmonica,  and I only have eight sets 
of plates in this first batch.  By the time  I've fixed eight slots I'll just be 
getting the hang of it and wish there were  more!  ;-)
 
Doug H
 
----- Original Message ----- 
From: Zombor Kovacs 
>To: Harp L Harp L 
>Sent: Saturday, October 30, 2010 4:13    PM
>Subject: Re: [Harp-L] Reed slot needs to    be shortened
>
>Hm. I surely don't have 100 years experience in reed design,    but whenever I 
>have 
>
>a length problem, I just choose a longer reed, and cut    it to the right 
>length. 
>
>Then I just adjust pitch with removing or adding    weight. So far it worked. 
>Certainly this was only for individual reed    replacements. As I understood in 

>this case we have loads of reeds so it is    different. However to shorten 
>dozens 
>
>of reedslots is also a lot of fuss. 
>
>Another way is to bolt the reeds to the reedplate with a thinner bolt    than 
>the 
>
>rivet itself. I have such bolts and nuts (size M1) , and they    allow some 
>adjustment so the reed can be moved forward to get the correct    gap settings 
>all 
>
>around. In fact this may be the quickest and simplest    way. Aligning the reed 

>will need some work, but it is not that bad. 
>
>
>
>May I ask in what way are those custom reedplates    special?
>
>Zombor
>
>
>
>
>
>
>----- Original Message    ----
>From: Vern <jevern@xxxxxxx>
>To: Zombor Kovacs    <zrkovacs@xxxxxxxxx>
>Cc: Harp    L Harp L <harp-l@xxxxxxxxxx>
>Sent: Sat,    October 30, 2010 7:00:41 PM
>Subject: Re: [Harp-L] Reed slot needs to be    shortened
>
>Sadly, it is not that simple.  Filling the slot isn't    the real problem.  
>Designing a longer reed having the same pitch and    response as the "correct" 
>reed 
>
>is.  Designing and fabricating such a    reed is more difficult than shortening 
>the 
>
>slot.
>
>Reed design    involves not only reed length but the thickness profile (the 
>non-linear    taper from rivet to tip.)   A reed of a given length works well 
>over 
>
>only a short range of pitches.  If this were not the case, all    harmonica 
>reeds 
>
>would be the same length!  Below that range, the reed    becomes too limber near 
>
>the rivet.  Above that range it becomes too    thin near the tip. In fact, the 
>lengths are different for every    hole.  Hohner and Seydel have had more than 
>100 
>
>years to optimize    reed design.
>
>Reeds are made for a set of about 20 standard metric slot    lengths that cover 

>four octaves from C3 to C7.    It is    unlikely that you will find a standard 
>reed 
>
>close to the desired length    and pitch for the overlong slot length.  
>
>
>You can probably    find a longer reed but it will be much lower in pitch.  
>Tuning 
>
>it up    to pitch would involve removing material near the tip.  A reed with a 
>paper-thin tip will not behave the same way as a reed of the "correct"    
>length.  
>
>Its response to player breath pressure would be different    and it would stand 
>out 
>
>from the response of its neighbors..
>
>It is    better to adapt the slot to the standard reed than vice versa.  
>Otherwise 
>
>you are faced with the same problem when it comes time to replace the    reed.
>
>Vern
>
>
>On Oct 30, 2010, at 3:05 AM, Zombor Kovacs    wrote:
>
>> I donno if I understand the problem correctly, but if the    slot is too long 
>>for 
>>
>
>> the reed, why dont you use a longer reed    instead?  Just cut it to the right 
>
>> length and there you have it. 
>> 
>> Zombor
>> 
>> 
>
>
>