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setarmaker
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[*] posted on 3-16-2007 at 05:41 PM
picture3


detaching from neck block
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setarmaker
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[*] posted on 3-16-2007 at 05:47 PM
picture4


detaching from neck block
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setarmaker
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[*] posted on 3-16-2007 at 05:49 PM


Look at who questionable is the missing Bracing on this one.
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Faladel
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[*] posted on 3-17-2007 at 04:44 AM


Please ¿can you post the lable??
Thank you
;)




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[*] posted on 3-17-2007 at 05:40 AM


Thanks for the update on moments of area, centroid etc. Ahmad. It is amazing how much can be forgotten after 50 years - which was the last time that I recall having carried such calculations!
If the centre of area calculation that I did for the Egyptian oud and Hieber lute soundboards is a good enough approximation - given the relatively standard belly profiles of ouds - then this is something that can easily be determined by someone who does not have the knowledge, time or inclination to get into integral calculus - or perhaps some easy to use software could be developed (if it doesn't already exist) to do these calculations - one that has graphics capability to read the profile geometry of a specific soundboard etc.
My low tech. calculation just requires dividing the surface area of the soundboard into squares and doing a bit of reiterative adding and subtracting to find the point where the areas above and below the "centroid" are equal. A bit tedious and prone to error but something that could easily have been done by luthiers in centuries past.
As a lute maker, I have always been interested in the bar below the bridge that seems to be a common feature of ouds. It is not found in any surviving lutes to my knowledge but I wondered if it did at one time - being replaced by the below bridge 'fan bracing' in lutes of a later period. I did instal such a bar as an experiment on one of my lutes and (to my ear) it improved the resonance of that instrument - but these things are very difficult to judge objectively.
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[*] posted on 3-17-2007 at 05:53 AM


Ahmad, it's interesting that there is a picture of Mr. Shahidi inside. Also, it's good to hear he is doing well.
Keep up the good work.
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[*] posted on 3-19-2007 at 05:48 AM
the bowl and label


All right. I’ve been so busy over the weekend and no production at all, except couple of things. Just look at the label. It says, (Amal= Made by) ( Ouste= Master) (Luthier’s name=Ali Al-Avad) (dated either 1967/3/1 or 1917/3/1) the second number of the year is under question. ( made in Baghdad) ( Al-dokkan= store # There is a dot right on top of #1 which could make it to look like a six in Arabic numbers. So its at least 40 years old. Up to you guys to figure that out.

I’m positive that from the ugly looking Titebond glue. This soundboard has been replaced by an unprofessional worker who did not even care about the label and did not cover it during restoration. We don’t do that, do we?

The neck had three quite big dents filled with wood filler! The neck looks to be intact but the owner says that it would bounce up and down by tuning high or low respectively. So, when the soundboard was detached, I noticed a small gap between the neck and neck block. I do not want to touch the neck, Since I believe that it could be adjusted and fixed by shimming. Also the neck block is split over the top of the wood pin all the way horizontally. Poor instrument has been Beat up or poorly repair? Either way, it’s sad and I’m in optimistic in putting it back together with your help and advise and give the health back to this old good sounding instrument. Please reply for any suggestions and advise. Ahmad

I think that AJAMI was just a nick name for the builder , since his generations were Iranian Arabs from Southwest part of Iran, or something els, I'm not sure! I just know the used to call him master Ali Al-Ajami.

OUD means Just one OUD but AL- AVAD may mean numbers of OUDs as a plural for OUD. Please correct me if I'm wrong. I just understand a little Arabic.
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setarmaker
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[*] posted on 3-19-2007 at 06:17 AM


I cannot say how beautiful this bowl has been made. Unbelievable workmanship, very simple, and the wood is outstanding.
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light.gif posted on 3-19-2007 at 06:41 AM


Now, It took me few minutes to balance this soundboard on a just needle type vertex. It actually took me 5 minutes to do this. When it was perfectly in equilibrium, with a little air movement it would start bouncing without collapsing. very much accurate to the tenth
of mm. Next using a self standing square, I marked the bottom edge of the soundboard. then measured from the mark to the tip of the needle. It was exactly 21.5 cm. Now make no mistake this is showing nothing yet. means we'll find out if the bracings where designed in write location which I doubt . because this instrument had completely lost it's original sound after the poor repair.
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[*] posted on 3-19-2007 at 08:54 AM


Ahmad - did you balance the soundboard without the detached (or missing) brace?
I am interested in how the ribs inside the bowl have been finished. It looks from the images that the interior has been left in a rough finished state and from the label image it looks as though a toothing plane has been used - to judge from the grooved marks on the ribs? This might be the same type of finish that I have found on the oud that I am restoring (see Restoration of an Egyptian Oud - part 1 on this forum) an unusual feature by all accounts. If so, could you post a close up image of the interior surface with a centimeter rule alongside for scaling purposes? Thanks
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[*] posted on 3-19-2007 at 08:43 PM


J,

Yes, I did balance it the way it was detached. I already joined my 5years old sitka which was bought from LMI. It's AAA and I'm sure its a pretty good quality wood. Pictures will be posted accordingly.

Due to layer of dust inside the bowl, I did not notice the roughness, but as soon as you requested it I did clean up and the answer is positive. Attached pictures show a type of fork edge plane work on the ribs. When I make setar or tar, I never smooth out inside of the bowl. It really effect the sound of high frequency strings. Sometimes when the sound sustains, you'll hear an undesired wolf tone. I'm not sure if the maker has been trying to eliminate the same effect. I believe that, grooves are about one (1) mm apart. The top ribs are both smooth.

I'll have bunch of good stuff in the next posting.
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setarmaker
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[*] posted on 3-19-2007 at 08:46 PM


this one is from the side ribs and the previous one was from the bottom center and left and right of it.
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[*] posted on 3-20-2007 at 08:55 AM


Thanks for the images Ahmad. Looks as though the interior finish of the ribs is almost identical with that of the ribs on my old oud.
I forgot to ask but is the underside of the belly also finished in the same way? It is on mine.
All very interesting.
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[*] posted on 3-20-2007 at 10:28 AM


Dear Ahmad

The lable of Usta Al avad Oud.

El Awo'waad means the man who plays Oud. I t is very common in Iraq to adopt a sure name from a man's career, but also can mean' oud making'. The year is 1967 because Iraqis were using different form of dating (the Hijri) at the beginning of the century. I do not think that 'Al Ajmi' related to this master.

Thanks for sharing.

Abdul
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[*] posted on 3-21-2007 at 09:15 AM


Hey all,
Abdul, thanks a lot for your time and corrections you made on the label and I’ll pass it to the owner. The owner was telling me t hat, he’s had the oud even before that date (1967) and he remembers when and how he had received it. I noticed that a little black spot has been dropped right next to the real number and caused the problem. It’s not ink at all, but the color is amazingly resembling. But It really doesn’t matter. I don’t want to touch it or remove it. Keeping it like this is more professional to me.

Yes J. that rib is also roughed by the same plane. I planed and sanded the new soundboard down 2mm. Do I need to go more? Then I cut the rose and did the inlay. Persian walnut Pick guard is installed. (It’s my own design and I hope you all like it) and This is the time for me to fined the centroid and mark it before putting any bracings on. As soon as this point is marked, the next wood be calculating the Height bracings. This will be a desired height for just one of the braces based on experience and the height for all other ones will be transferred by proportional spanning. For example, If I start my first Brace below the bridge with height of 15 mm and span of 260mm then my factor would be 15/260= 0.05769 for all other spans. So where I have span=370mm then the brace height would be 0.05769 x 360= 20.7 mm and so on. Now what I need from you is to tell me what should I try for my first height by your experience? I’d rather to use NAHAT’s bracing method of height. The date for this oud is as follows:

top plate's length= 500 mm widest span= 360mm So, just please give me a good height of either one of bracings, so I can start this research and to see where is going to be the location of the last bridge by keeping the centroid untouched.

I’ll post some pictures for your info. Thanks a lot for sharing your skill and knowledge.
Ahmad
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[*] posted on 3-21-2007 at 10:52 AM


Let me know if you need explanation on the photos. The most important message in the up right image is that how we really can keep the centroid in the same place and how wisely we can determine what we want. This can be a quick answer to Dr. oud's question regarding asymmetrically distributed bracing. It cannot be worst that this situation. Isn't it right?
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[*] posted on 3-21-2007 at 11:02 AM


I just post some pictures of my decorating although they are not our subject and just so you don't get bored too much.
The bottom right photo shows where I had my needle point standing also where the Yellow self standing square was marked as the edge of the soundboard. the top right picture may confuse you! don't worry, the fingerboard is not glued yet. I'll do that when the soundboard is adjusted perfectly home.
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[*] posted on 3-23-2007 at 08:20 AM


All right, I have finalized the soundboard’s thickness based on NAHAT’s samples and Dr.'s verifications e.g. 1.8-1.85mm in the center tapering to 1.00mm to 1.3mm to the sides edge. Obviously, my soundboard wouldn’t be balanced on the same exact centroid that I had before. Because the first trail C.G was with the same thickness all around the shape. When tapering to1.3mm towards treble strings against 1. mm for the bass strings, your actual centroid shifts toward the heavier half of the soundboard. See the red dot on the soundboard. But, no problem at all because when I’m going to locate my last and key bracing, I will set the soundboard on the real original centroid and so, this will guarantee remaining of the centroid. Now, buy doing this, your last bracing may not necessarily stay parallel to the others which makes sense, since we play with it to meet the balance on the centroid. I’ll post bunch of pictures from the process and I’ll try to send a video clip on the web as well , but this may take a while for me.

One thing that I need to emphasize again is that the process is to be utilized when you have good quality wood and skills in hand. I’m just trying to research on the physical and geometrical part of this huge deal and to find some realistic relationship between them.

I’m still waiting for someone who could tell me what would be the best average height of bracing to consider. I’d appreciate it.
Ahmad
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[*] posted on 3-24-2007 at 06:31 AM


Ahmad - I didn't understand your earlier response to my question about the surface finish underneath the old soundboard. Has the underside been finished with a tooth bladed plane - like the ribs of the bowl have?
I do not have any historical data on ouds but I do for lutes. If it is of interest, I have checked my files for measured belly thicknesses from surviving lutes of the late 16th to 17th centuries. For 12 instruments belly thickesses - regardless of the size of a lute (from soprano to bass) are all generally well below 2mm in thickness and often closer to 1 mm with quite a wide variation in thickness on individual instruments. Note, however, that the surviving bellies are somewhat worn after 400 years or so and most of these measurements were taken close to the edge. Nevertheless, these tend to confirm that average belly thicknesses for lutes are similar to those of the oud - to judge from the data provided by Richard.
As for choosing the precise thickness for a new belly that would depend upon the material of the soundboard and its particular physical characteristics to some extent. Likewise for the barring. These are often found to be assymetrical in both placement on the belly and in shape - which, as I understand it, is often the case with ouds as well.
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[*] posted on 3-24-2007 at 11:38 PM


J,
I must have misunderstood you first time. sorry about that. The answer to your question is negative. The back of the soundboard is just in a regular shape. It's smooth but not perfectly glazed. Thanks for the info you posted about soundboard thicknesses. It seems like you are the only one who is wiling to help. I certainly appreciate it. Well, I did not want to wait too much, so just went ahead and chose a 22mm for the widest braces' height and finished my bracing. Now I'm going to start the most important part of the journey and work on the last bracing by the method which is under investigation. I'm receiving a pretty good tap tone so far, but taping on the part where the last bracing is not installed yet is somewhat flat and it tells me that I need some more bracings around the tapping area. after the last bracing is installed, I'll check the tap tone by my experience. If I'm not getting the desired sound, I can always sand and reshape the bracings to approach that, But I still need to keep the centroid stationary in my modifications until, I have the desired tone and centroid.

I hope that I'll be able to wrap up the project in couple of days so I can post all necessary pictures and descriptions. thanks again, Ahmad
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[*] posted on 3-26-2007 at 11:45 AM


I'm back happy! I think the project has a very satisfying result. Everything is put on now. Before even gluing, I installed one string of each size and checked the sound. As I was guessing, it sounds very nice. the tap tone on free hanging soundboard was really good as well. I did the whole process as I explained and as you can see from the pictures. Pictures are from finalizing the soundboard's thickness and so on. I used a perfect size and elastic bonji cord and installed it around the edge. This was My simple Idea to help th bowl pushing towards end of bracings from both side. Please see pictures and notice wood blocks I have used to ensure the compression. The centroid is perfectly untouched and coincide with C.G. as you see in the photos. Next I made my custom band for my inlay since I did not have any in hand. To do this I just utilized the old soundboard as a mold.

I'll get back to you when the instrument is ready to play.
Ahmad
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[*] posted on 3-26-2007 at 11:51 AM


see the progress. What I did was to just tape the bracings on the back and then balanced the soundboard on the centroid by using my last bracing on the top of soundboard. This allowed me to move the last bracing and try to make the equilibrium. As soon as that hapend, I marked the location and transfered it on the back.

I did this one more time after I actually glued all other bracing and did get the same result for the position of the last bracing. Man this sounds beautiful.
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[*] posted on 3-26-2007 at 11:58 AM


more pictures.
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[*] posted on 3-27-2007 at 05:04 AM


work in progress.
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[*] posted on 3-27-2007 at 05:09 AM


bracing ends were perfectly attached to the top rib with no failing. I think the bonji cord did a wonderful job. Bonji cords may not do the job if the ribs are too thick or extremely solid. if the top rib is 2.4mm to 2.7mm you'll get the best result.
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