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FastForward
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Analysis of Nahhat Bracing
I found an image of an Abdo Nahhat oud and wanted to determine the relative spacing between the braces, here is what I found (see image).
I assumed that the total length is 49cm.
- String Length is 60.
- Distance between braces around the bridge is not even, the brace towards the neck is closer.
- The width of the area around the bridge is 9.1cm (actual number might be 9cm)
- The braces are not entirely parallel. The layout varies around the bridge and large rosette.
The info is quite interesting. Would love to hear your opinions and feedback.
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fernandraynaud
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Hi, Edward,
Can you clarify: do you know the scale is 600 mm and the body 49 cm? is this a photo of a soundboard taken off the instrument that this Michael Cone
published? Or is it shot the from top with braces drawn in? By hand? At what accuracy do you think the braces are drawn? Is left left or is it
reversed? What are the curved "braces" on the right of the main soundhole?
For me, and I'm no luthier, an interesting thing is that most every oud I have looked at seems to have a roughly (anyway) similar layout, except for
Sukars. It is fascinating having a chance to examine several instruments from the same maker. Sukars lack the little partial braces in the center of
the main soundhole, and instead there are braces on both sides of the main soundhole that are parallel to the length and that join the 181.5 and 87.5
braces about halfway between the soundhole and the edge, creating little "chambers". By tapping and recording into an analyzer I can see that Sukar's
soundboard this way seems to create more distinct "domains of resonance", resulting in the Sukar's typical greater number of distinct "resonance
peaks" (and perhaps its greater volume) compared e.g. to a typical Egyptian.
A curious thing, by the way, about Sukars is that the different models have great differences in feel and timbre, even though the basic design seems
to be common. A main difference appears to be the woods used on the neck and the bowl. The "deep-sounding" model 14 with its black walnut bowl sounds
very different from the 212 that uses lighter-colored types of walnut(?) in alternating ribs. I'm scratching my head.
I'm not belittling the old Nahats, but there's no question that the modern Boutique Guitar is an amazing powerhouse compared to older guitars.
Guitar-making has suddenly enormously progressed in the last couple of decades, a combination of science, better tools and unprecedented devotion, and
a lot of novel ideas have appeared that can probably be tried on the oud without destroying its character, for instance many alternate bracing designs
that have vastly improved volume and tone balance on Classical Guitars.
There's an interesting series on YouTube, search for "Gourmet Guitars", that features interviews with many prominent luthiers, who discuss their
fascinating pet ideas. If I were building instruments, I'd definitely study all of these.
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FastForward
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- I am not Edward, Ibrahim would be more accurate.
- I made an assumption that the length is 49cm. Based on that and from the image the scale can be computed and it is 60cm. Any dimension can be
computed using (# of pixels)*49/330.
- the photo is available online, I just googled Nahat bracing and it was one of the images that showed up.
- the soundboard was not taken from the oud. You can determine brace locations by inserting a very bright light inside the oud and taken the image in
a dark room. So left is bass, right is treble. Its a right handed oud I believe.
- the curved braces are nothing but the electric cables for the light that was inserted 
- I am not too interested in Guitar braces, though I have seen most of the series you referred to.
- I have seen different variations on the bracing where some braces are missing or others are added. I am more into trying to analyze the pattern
above and would like to see other examples/patterns.
I have seen Faruk's bracing for some ouds and he has one of the braces slanted and not parallel. There are also other examples. What is more
interesting above is that its not just one brace, there are several.
I am also interested in comparing dimensions, such as the area around the bridge, distance between the bridge and the braces around it, etc...
I know the Nahhat pattern in Dr. Oud's book is different from this and would like to see other variations within the Nahhat ouds.
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FastForward
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It seems that Jameel did some work on this oud.
http://www.khalafoud.com/cone_nahat.htm
Jameel can you clarify this and potentially substantiate some of the dimensions assumed/computed?
I am also wondering about the size of rosettes. They seem to bigger after the restoration. I would guess that the image above was taken after
restoration.
Also, any chance that you have a sound sample.
Thanks,
Ibrahim...
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Jameel
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Michael Cone did the work on that oud. Nahat bracing is all over the place. It's a secret yet to be "unlocked". The rosettes are original size, as far
as I know. I might have a sound sample. I'll do a little digging....
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FastForward
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Thanks for the clarification Jameel. Yes, the Nahat bracing is an interesting subject. Too bad Elias's diaries and notes were thrown away.
The rosettes are definitely a different size on the restored oud. Here is an image I made for comparison. The main reason that made me believe this
was the rosette sizes determined from the above image which shows a small rosette with about 4.6cm diameter.
Thanks again Jameel.
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farukturunz
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Quote: Originally posted by FastForward  |
- Distance between braces around the bridge is not even, the brace towards the neck is closer.
- The width of the area around the bridge is 9.1cm (actual number might be 9cm)
- The braces are not entirely parallel. The layout varies around the bridge and large rosette.
The info is quite interesting. Would love to hear your opinions and feedback.
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Thank you FastForward for posting this photo and for firing off some very important questions about very imprortant points on bracing.
There is no need to remark about the importance of Abdo Nahat. To me he is one of the very rare and unusual Oud Constructors who has realised the role
of the locations of the braces and tried to arrange the composition of the overtones by differentiating the largeness of the areas lined off by the
braces. What a surprising and confusing(!) approach of a great master which do not match with our fascination of SYMMETRY!
Idolizing the symmetry must be the manifestation of our "sense of justice"
But, Physics and physical phenomena do not "have" any "sense"! They are indifferent and insensible. If we are seeking for any success when dealing
with physical objects and trying to make them obey to our will, then we also must be indifferent and insensible against them
I may try to make my remarks more understandable by expanding the physical counterparts of these metaphors.
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jdowning
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It is unfortunate that the restored oud now has enlarged sound holes as the original sound hole diameters may have been a key element in the sound
board geometry (it looks as though the original rosettes have also been replaced!). I take it that the image on the right hand side is that of the
original oud - more or less as it left the hands of Abdo Nahat.
The early lute makers did not use linear measurements to lay out their sound board geometry but - having determined the sound board profile required -
then laid out the rest of the geometry by proportion using only simple dividers. The scribed layout marks can still be seen on some of the sound
boards surviving from the 16th and 17th C. Also - and I agree with Faruk Turunz here - that the old luthiers did not feel bound by precise symmetry.
Often the exact centre lines are a little 'off', braces set slightly askew, sound hole centres offset a little from the centre line, sound board
profile a little asymmetric etc. The old masters were in the business of making fine lutes for profit so made them as quickly as possible (and with
great skill) without troubling about what they knew from experience was unimportant detail.
And so it is likely to be the same for the old oud makers - this fine oud by Abdo Nahat being a case in point
While it is not possible to be precise when working with reduced sized images that may also suffer from some degree of optical distortion the
following geometry is proposed as one that appears to fit nicely - as closely as I can determine given the above limitations. The geometry is laid out
using dividers as follows:
Starting with the profile of the sound board as far as the neck joint A, the overall length A-M is equally divided into 5 parts. The front edge of the
bridge K is located at the first part, the centre line of the small sound holes G on the second part, the centre of the large sound hole E on the
third part and a brace C on the fourth part. (This also agrees with the classic oud proportions where distance A-E = E-K and MK is half A-E (or E-K).
Usually A-E and E-K would also be 1/3 string length and the same length as the finger board - but in this example the finger board is too long to
conform to 1/3 string length. So is the neck original or another 'restoration improvement'?).
The sound hole diameter is 1/3 the width of the sound board at the sound hole centre line (this conforms with 15th C lute design geometry of Arnault
de Zwolle and later). The diameter of each of the small sound holes is 1/3 the diameter of the large sound hole. The location of the centres of the
small sound holes is given by a Pythagorean right triangle of 3:4:5 relative proportions (dimension 4 being distance E-G.
The front edge of the neck block B is located equidistant between the neck joint A and brace C i.e. A-B = B-C.
The below bridge brace L is located midway between the bottom of the sound board M and front edge of the bridge K. i.e K-L = L-M
Brace J is placed mid way between the front edge of the bridge K and Brace H at the widest point of the sound board. i.e H-J = J-K
The below sound hole brace F is placed the same distance above the small sound hole centreline as brace H is below i.e. F-G = G-H.
Two half braces are positioned on the centreline of the large sound hole - on either side of the sound hole and finally a brace D is placed above the
sound hole so that distance D-E = E-F
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farukturunz
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| Quote: Originally posted by Jameel | | Michael Cone did the work on that oud. Nahat bracing is all over the place. It's a secret yet to be "unlocked". The rosettes are original size, as far
as I know. I might have a sound sample. I'll do a little digging.... |
Dear Jameel,
I really appreciate your fastidiousness in choosing the words like "unlocked". I as not being so fastidious as you are most probably might choose a
word like "to be inspired of". Any way I have a sincere respect towards your thundering efforts for understanding the great "secrets" of old
masters.
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Jameel
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I like your words "to be inspired" better than "unlocked"! But your appreciation for choosing words carefully is equally inspiring. Thanks Faruk!
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Jameel
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Just a quick reply here. The original oud is not completely original. Note on the pre-Cone oud that the wood around the smaller holes is not a
continuation of the face wood. This oud underwent some prior restorations before Michael took possession of it. I'm guessing that the original sound
holes were damaged in some way, and the original binding around the holes was as well, so new rosettes were made in the style of Nahat (made by me),
the replaced wood around the holes was removed and instead of compromising the soundboard further Michael put a thin binding around the inside edge. I
should add that the smaller rosettes I took directly from a Nahat, size and all. I originally made them for an oud I was building, but later didn't
use. Michael and I started corresponding about this oud and I mentioned the extra rosettes I had. I sent them to him and they were a perfect fit
(after removing the "replaced" wood around the small holes). Given that I took these rosettes from an completely orginal Nahat, I think that's a
pretty argument for the current size of the holes.
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FastForward
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Usta Faruk:
Thanks for the comments. True, we are fascinated by symmetry for various reasons. But in the oud case, symmetry does not necessarily equal good tone.
I am just fascinated with the approach of the Nahhat.
I have also noticed that on some of your soundboards, you have used slanted braces around the bridge. You and the Nahhat's have different experiences
and different tonal requisites which is manifested in the variation of your soundboards bracing from the Nahhat. But all is fascinating and
interesting.
---
John:
Very nice and inspiring analysis.
I think the deviation from symmetry is something done on purpose rather than imprecise placement by Nahhat. Looking at the fine woodwork he was doing
I wood be surprised that he would err by this much in a much simpler task. Unless, of course, this oud was not made directly by him rather by a new
apprentice. It could also be one of the " lower end basic models" that probably were not cared for as much, if such ouds existed! It definitely is not
as ornate as many other Nahhats.
Yes, the oud on the right is the original one (apparently it has had some modifications so its not 100% original).
I think that distances A-E , E-K are about equal given the potential visual distortion and measurement errors. The current deviation is about 4mm from
even, 19.6 and 20.4cm as opposed to 20cm. I will measure the width of the soundboard at the center of the large rosette to to compare it to the large
rosette and will get back to you on this one. I will also measure the other distances and put an image along with the one you provided. Overall,
truly inspiring and fascinating decomposition.
---
Jameel:
Interesting story. So I guess the wood added around the small rosettes after the first restoration was oversized. In fact, we can argue upon closer
inspection of the small rosettes of the photo on the right that the wood is partially blocking the rosettes.
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jdowning
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Thanks for the factual update on the history of the last restoration Jameel. I had no idea about the prior background only taking the information
originally posted at face value.
So, it is safe to say that the oud in its current state may not represent the oud that left the workshop of Abdo Nahat - at least we have no way of
knowing for sure.
So what about the sound board that existed prior to restoration? If this sound board was considered not to be 100% original, why, specifically, and on
what evidence, is that?
I think that FastForward's suggestion - judged by the oud's lack of decoration and deviation from perfect symmetry (although slight) - that the oud
might have been an instrument made by an apprentice could have some virtue (but do we have any written evidence to support this speculation about
employment of apprentices by Abdo Nahat - probably not?). However, an apprentice would surely not have been left ,unsupervised , to his own devices
but would have been required to follow a geometry dictated by the master? Or, alternatively, was this an earlier sound board (perhaps one of many
experimental models, of necessity quickly put together and devoid of unnecessary decoration) made by the master as part of his 'learning curve' to
make a better oud? In which case - and either way - a geometrical construction that is straightforward and fits - within a reasonable tolerance -
might surely be a good candidate for consideration against a geometry that is otherwise a complete mystery?
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FastForward
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Since the soundboard has had some work, it would be great if we know the extent of repair work that was done. Was the bracing changed? I realize this
info may not be available.
Anybody else with an Abdo Nahhat that can post a similar photo so that we can make some comparisons? I will be glad to do the measuring and marking
on the images.
An apprentice could very well be a young member of the family, e.g., one of his son at an early age. Such is a typical practice of craftsmen families
in Damascus at the beginning of the cenutry. I am not sure this was an experimental oud by Abdo himself, this is oud was made in 1925 and so the
learning and experimentation days of Abdo Nahhat himself were most likely well behind him, or maybe not!
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FastForward
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Update,
The large rosette dimension as is (after enlargement) is not 1/3 the width at the center line. One third of the width is 70px, Whereas the large
rosettes is 81. BUT, if you reduce the size a little bit, and consistent with what the size would have been based on the other image, then 5px on each
side would make the rosette 70px, exactly 1/3 of the width of the soundboard at the center line of the large rosette.
I can see that the distance between the brace in front of the bridge and and the bridge (K-J) is not equal to H-J. The ratio is 3:2 rather than 1:1.
At the top near the neck block, I think the distance between the brace above the large rosette and the neck block is divided into 3 equal segments.
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jdowning
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Thanks for the update FastForward. One difficulty is that we are both working from the same low resolution 'fuzzy' image in order to arrive at
conclusions about relative proportions.
I see that I forgot to include the brace immediately below the neck block in my analysis!! It does not seem to be a perfect fit but I would accept
your conclusion that the intent of the maker may have been to divide distance B-D into three equal parts. This again is a practice found on some of
the old lute sound boards.
There is a shadow under the bridge that may be some kind of rigid reinforcement plate (?). If - for the purpose of placing brace J - this was taken as
the front edge of the bridge (rather than the front edge of the tie block) then the 1:1 ratio would apply.
Jameel notes that the sound board - as it was prior to restoration - had the (original?) sound holes partly filled in with wood to reduce their
diameter. I wonder why someone (most likely then not Abdo Nahat or a family member?) took the trouble to do this. Did they, perhaps, feel that the
sound hole diameters were too large and so did not conform to traditional proportions?
Detailed information, measurements and images recording the extent of the restoration work that was undertaken might be very helpful.
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jdowning
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For completeness I have reviewed the proposed geometry to try to find a possible geometrical relationship assuming that the larger diameter sound
holes chosen for the restoration are in fact the original diameters. The increase in sound hole diameter does not change the proposed arrangement of
the bracing etc as there is plenty of space between brace locations D,F and H to accommodate the holes without having to reposition the braces.
To establish the diameters of the large and small sound holes it is necessary to turn to the Pythagorean 3:4:5 triangle that is used to determine the
small sound hole centres relative to the main sound hole centre. The diameter of the small sound holes is then given by 2 units of the triangle and
the large sound hole diameter as 5 units. Again, this match has been determined from the low resolution image so may be subject to some error but
could be verified more precisely by measuring the restored oud.
The other relationship that seems to fit is that the centre of area of the rectangular plate under the bridge is located mid way between brace H at
the widest part of the sound board and the bottom of the sound board M.
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FastForward
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John, the shadow under the bridge is not a plate, its the bridge itself. If you look at the image of the oud itself rather than the bracing, you will
notice that the bridge has a wide base and that the part to which the strings attach is offset to the inside. This typical of the bridges made by the
Nahhats. Though, your observation is quite interesting in the sense that this extended bit of the bridge levels off the distance mentioned and
provides a 1:1 ratio.
I would still think that the size of the large rosette prior to restoration is almost accurate. In Dr. Ouds book, the size of the large rosette, which
is based on a Nahhat, is 11.6cm. So I would still go with the 1/3 of the width soundboard theory.
The 5:2 relationship between the large and small rosettes could very well be true. I hope that some members with a Abdo Nahhat can measure their
rosettes and update us on these measurements.
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jdowning
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OK that is good. I was confused by the fuzzy bracing image as the bridge appears to be proportionally much larger than the bridges shown in the before
and after restoration pictures of the oud.
To complete this exercise I was curious to find out if there was a simple (non mathematical) geometrical construction that would define the profile of
the oud and which might have been used by Abdo Nahat.
The image that shows the bracing was printed onto card and then cut out to give a pattern of the oud profile. This was then traced on to paper as a
reference.
For this method of construction the required width of the sound board is divided in two to give the half width X-Y. This is then divided into two
equal unit lengths X-A and A-Y. The construction line is then extended by another equal unit Y-Z. These three units form the base of a Pythagorean
3:4:5 triangle N X Z. Point Z is the centre for scribing an arc of radius R1 which defines the curve of the upper section of the sound board (repeated
for the opposite side from centre W).
Note that this is the same construction that is used to define the upper sound board profile of ALAMI's Al-Arja oud (See 'Oud or Lute' on this forum).
However, unlike the Al-Arja oud, the bottom section of the Nahat sound board is not described by a semi circle but has a flattened profile in the form
of an ellipse.
To form the ellipse two 3:4:5 triangles are constructed using unit X-A as the base. Two pins are positioned at A and B and a piece of thin cord is
looped around the pins of a length that produces the required curve using a pencil (see attached image). The curve is blended in smoothly using arcs
drawn by R1 and R2. (repeated for the opposite side)
It can be seen that the match with the card template profile is very close taking into account possible slight image optical distortions, pencil lead
line thickness, reduced scale errors etc.
An 'acid test' to verify this method might be easily done at full scale using an original Abdo Nahat oud (other Nahat ouds may have different profile
and geometry) to verify the profile (given that there might still be some slight asymmetry inherent in a hand built instrument profile - as there
always is).
In light of the importance of the Pythagorean 3:4:5 triangle in this proposed construction as well as the use of a 3:4:5 triangle to establish the
relative dimensions of the larger sound holes (previously posted) it would seem that the larger diameter, post restoration sound holes are also good
candidates for being original?
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farukturunz
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| Quote: Originally posted by jdowning |
To complete this exercise I was curious to find out if there was a simple (non mathematical) geometrical construction that would define the profile of
the oud and which might have been used by Abdo Nahat.
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Thank you jdowning for giving this geometrical construction. This and similar proposals by laying a method grounding on a "principle" may help
searches in standardizing the oud form.
Kind regards
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jdowning
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Thank you farukturunz - I agree with you entirely. As so little (if anything) remains on record about how the great oud makers created their
instrument profiles or bracing geometries, the only solution left is to 'reverse engineer' - testing different possible solutions against the
surviving instruments to try to find a match. The simpler the geometrical solution and the closer the match (within a mm or so) the more likely it is
that a particular solution may have been the one used by a particular luthier.
Many researchers interested in the lute have tried this approach - with some (apparent) success - although there are some surviving lutes by the great
masters that currently still defy an obvious solution.
The situation with lutes is, perhaps, a little better than it is with the oud as most of the surviving lutes are in the (hopefully) safe custody of
major museums where conservation (rather than restoration) is a paramount objective. Many of the museums - although they restrict access to their
instrument collections (conservation) - do offer full scale drawings/ detailed photographs for the benefit of researchers and luthiers.
Most old ouds are probably in the hands of private collectors so the only way to collect important historical data, recorded for posterity about the
instruments, would be to persuade the owners to carefully outline trace and measure their oud, analyse the geometry, and post the results for the
information of all interested or, alternatively, to post optically undistorted images so that others might attempt an analysis (and then post the
results).
There is definitely (from my observations and in my opinion - but not surprisingly!) a very close similarity between the geometries of some old ouds
and lutes - although the exact relationships have yet to be examined, established and confirmed through further research. All worthwhile objectives
but time consuming to pursue in detail!
Nevertheless each individual could contribute, with a little effort, to what could possibly become an important and accurate historical data base.
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Danielo
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Hi John,
actually a non-insignificant number of these private owners are on this forum ! I think you don't need persuasion, but rather give some clear protocol
in order to make the measurements accurately without special tools.. I agree it would be very important to have a database of such data.
regards,
Dan
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jdowning
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Thanks Dan. I will give some further thought to this under a separate, dedicated topic as here - on this thread - we are discussing only one possible
geometry of an oud by one important maker. There will, of course, be other variants as there is with surviving lutes. If you are correct about the
historical ouds in private ownership then Mikes Oud forum would be an appropriate place - a potential repository - to collect and share this data.
The starting point would probably for each owner to provide good quality, 'full face' undistorted digital images of their instrument(s) together with
some basic linear measurement information (string length etc.) and maker, date etc. This would at least allow an initial preliminary assessment of the
geometrical possibilities to be made - to then be verified by a more detailed examination by each owner.
Quite busy with other projects at present so will try to get around to it later this year,
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jdowning
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Here is another possible alternative 'lower half' geometry for this Abdo Nahat oud. This (with the potential inaccuracies of a reduced scale analysis)
gives results that appear to be close to the original profile but that do not depend upon the additional complication (and potential error) of string
and pins for the final result.
The attached image should make the construction clear.
A square ABCD with diagonals AC and BD is drawn with sides equal to the oud maximum width. The upper profile of the sound board and overall length is
constructed using the geometry previously posted - based on a Pythagorean 3:4:5 triangle with an arc described by R1 from centre Z etc.
The arc described by R1 and an arc described by R2 from centre N are drawn to intersect at point E.
An arc described by R3 with centre at E and touching the centreline of the sound board is drawn to intersect diagonal BD at F (repeated for the
opposite side).
Finally, an arc drawn by radius R4 from centre F - touching and blending into the arcs described by R1 and R2 - completes the profile of the lower
part of the sound board.
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FastForward
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I have been busy the last few days and haven't had a chance to read through the comments thoroughly.
Wow John, Every contribution is more astounding than the previous. I second what you say regarding the individual contributions. I think that we
should have an extended database of such info. It would be great if it could be hosted here at Mikeouds. I think the first step is to provide a simple
set of standardized instructions that the average Joe or Mo can follow to provide the data.
Unfortunately, so much precious info has been lost and there is no way to get it back. Hopefully our combined efforts can provide a wealth of info
for the future.
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