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[*] posted on 11-18-2007 at 01:18 PM
Ancient Scales of Measurement?


Does anyone recognise the following 14th C Arabic linear scales of measurement:
- asabi'
- asabi' madmuma
- shibr
- 'aqd.
- and if so, what units do they represent when converted to present day metric measurements?

Is there any connection between the above and the following scales and is the conversion of these to metric correct?
- isba' (Arabic) and angusht (Persian)= 2.25 cm.
- isba madmum (Arabic) and angusht mundam (Persian)=4.5cm.
- shibr (Arabic) = 27cm. (see above also)

The above are mentioned in footnotes from "Studies in Oriental Musical Instruments" by Henry George Farmer
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[*] posted on 11-18-2007 at 01:35 PM


Am not sure of the exact equivalent in cm but the persian equivalents seem logical:
Isba' is a digit, the width of a finger
Isbaa madmoum should be the palm
Shibr is a span, the width of spread fingers.
These terms are still commonly used as approximative length measurments.

I am not familiar with 'aqd but I think means "knot"
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[*] posted on 11-18-2007 at 05:56 PM


Thanks ALAMI - I guess that there is a connection between the phonetics "asabi" and "isba'" - one plural the other singular perhaps?

According to Farmer 'aqd' is equivalent to 2.25 cm - i.e. the same as isba (or angusht) - as he states that a length of 29.25 cm as equal to 1 shibr + 1 'aqd.

"La metrologia non e scienza, e un incubo" (metrology is not a science, it's a nightmare)" G. de Sanctis !!
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[*] posted on 11-19-2007 at 09:49 AM


Unfortunately Farmer does not indicate how he arrived at the metric equivalents of the ancient measurements that he refers to. He quotes a "shibr" as equivalent to 27 cm. Perhaps Farmer assumed that this unit was equivalent to a "foot" which when divided by 12 gives an "inch" (in the English system) - equivalent to 2.25 cm (isba)? However, the ancient Egyptian "foot" apparently was a consistent standard throughout history and measured 300 mm. The "digit" in this scale may have been 1/16 of the Egyptian foot measuring 1.88 cm - but I don't know for sure.
This lead me to investigate further and as result found the thesis "A History of Measures" by Livio C. Stecchini - a fascinating in depth study running to several hundred pages. This can be downloaded from http://www.metrum.org
I doubt whether it will answer my questions about Farmer's units but it will be worth reading for its own sake and for future reference.
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[*] posted on 11-19-2007 at 07:43 PM


Last year I got a copy of "Kanzol-tohaf" and actually posted something about it in the forum. The book is unique since it was written in Persian (usually manuscripts of this type were written in Arabic) and it has pictures of instruments and the way they are made. In the book the measurements of the Oud's overall are written as 30 "Angosht" (fingers) or 3 "Dasts" (hands). The dast is also known as a "Vajab" (which could be arabic). It's the distance between the tip of the thumb and the tip of the pinky. These measurements are still used today to quickly size up.
The book doesn't say anything about the measurements. The 2.25 seems to be a good estimate since the length of the oud would be about 67.5 cm, and if you use (my) hand, it would be about the same.
Other measurements are: width = 15 fingers, and depth = 7.5 (the depth should be half the width the book says). This makes the instrument shallower than the modern version. Interestingly, the oud of this time (and Farabi's time) has 5 strings and has several frets.
If you check out youtube, there is a Turkish group called bezmara. They use a reconstruction of the shahrood (the "king" oud, a very large out) and a normal oud.
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[*] posted on 11-20-2007 at 02:38 AM


It's interesting to note that turning the ancient measurements into cm results in instruments of a given size, whereas the ancient measurements give various sized instruments depending on the size of the makers hands, and I'm thinking we could all get "tailor-made" instruments perfectly proportioned for us if we got a maker to use our own hands for the measurements...



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[*] posted on 11-20-2007 at 06:06 AM


Thanks - in the thread 'Question - Big Ouds, Little Ouds' I refer to a large oud converted to metric units from the original dimensions. Farmer, in his translation of the 14th C text gives the dimensions of this oud as length = 40 asabi madmuma, width = 16 asabi madmuma, depth = 12 asabi with the bridge located at 2 asabi from the bottom of the bowl. Farmer converts these dimensions to 180 cm, 72 cm, 27 cm and 4 1/2 cm respectively. He also gives the length of the neck and pegbox as 29.25 cm = 1 shibr + 1 'aqd. These measurements do not make much sense to me and I was wondering if there are errors either in the original text or in the transcription by Farmer?
What might work would be to assume that the larger units of asabi madmuma (equal to 4.5 cm according to Farmer) are in error and should be asabi instead (2.25 cm according to Farmer). This would give an oud of about 90 cm length by 36 cm wide and which would translate into a string length of about 90 cm - 4.5 cm = 85.5 cm. This would also almost fit with a neck length of 29.25 cm which should be about 1/3 of the string length (the depth measurement still seems way out of proportion though). This would still be a very large oud (of fairly narrow, almond shaped profile - like some early 16th C bass lutes by makers such as Maler and Frei) but with a string length that would be practical (some 16th bass lutes had string lengths of over 90 cm). However, all of this is just speculation that would need to be checked by reference to the original document.

Ouds can still be custom made to suite players of different hand sizes (and likely are?). However, the use of a hand (or finger, thumb etc), as an ancient unit of measure, assumes that everyone is of equal stature - with same size hands, fingers etc.
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[*] posted on 11-20-2007 at 06:16 AM


See also the thread "Oud or Lute" by Dr Oud in the Ouds Project Forum.
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[*] posted on 11-20-2007 at 07:30 AM


I know of 2 instances of ancient middle eastern instruments being recreated for modern ensembles (Bezara in Turkey and Mejnun Kerimov in Azerbaijan). In both, they heavily depended on old paintings and carvings to make estimates of the instrument length. Sometimes, these paintings are exaggerated. I think Sazi makes a good point about the lack of real standards and tailored instruments.
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[*] posted on 11-20-2007 at 10:44 AM


It would be a mistake to assume that early civilizations lacked real standards of measurement - quite the contrary. The Egyptians and Romans, for example, didn't perform their great feats of engineering and construction by "rule of thumb" so to speak - they had very precise standards of measurement. Just because a unit of measurement was called a finger (for example) does not mean to say that they actually used a finger for measurement (except for the average person making a quick and very rough check in the local rural market place perhaps).

I would agree that instruments depicted in paintings are often exaggerated (more often than not) so are not a reliable source from which to try to re create an early instrument. Artists will often work by convention or from memory or will misrepresent or omit important details like strings, frets or numbers of pegs etc..

For comparison purposes I have superimposed a half outline of the oud described by Farmer (drawn to my speculated "corrected" dimensions noted in my previous posting) over a sketch of a small bass lute by 16th C Laux Maler. The sketch of the lute is a recreation that I made many years ago based on a surviving soundboard by that maker. Both outlines are to the same scale with the bridge position as a common data point. Both instruments have a relatively long narrow 'almond shaped' body with low bridge positions. The oud also has a relatively shorter neck than the lute.



Mahler Oud revn reduced (375 x 600).jpg - 32kB
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[*] posted on 11-21-2007 at 02:04 PM


Thank you Peyman, I thought it may help to partly explain some of the many variations in dimensions of ouds made in times and perhaps rural places, away from centres of learning, where tape measures, calculators and the like were not common everyday household implements.



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[*] posted on 11-26-2007 at 10:30 AM


For those of us who do not read Arabic, I have now had it confirmed that the unit "asabi" is the plural of "isba".

See my latest posting in "Question - Big Ouds, Little Ouds" for an update on Farmer's interpretation of the dimensions of the Ibn Al-Tahhan oud.
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[*] posted on 11-26-2007 at 03:23 PM


John, I think I got something for you.
It is an arabic manuscript in the university of tokyo.

Author: Hasan Ibn Umar Ibn Ma'ruf Ibn Abd Allah Ibn Mustafa al-Shatti - (1205-1274 / 1790-1858)
Title: Bast al-raha li-tanawul al-misaha .

Source: http://ricasdb.ioc.u-tokyo.ac.jp -

The link to the full pdf: (5Mb 44 scanned manuscript pages)

http://al-mostafa.info/data/arabic/depot3/gap.php?file=m003359.pdf

It won't be easy to translate, I'll do my best later if you think it would help.
Roughly, the author is talking about 3 different systems:

Zira' (arm) = 2 shibr (spans) ; shibr = 12 isba'

Another Zira' is defined as equal to 27 isba'

then the third is called Zira' Hashemia and is used in topography and is in fact 1.3 times the first Zira'
the Zira' Hashemia = 32 isba' = 8 fists ; where a fist = 4 fingers and a finger = 6 hairs

He mentions also the carpenters' Zira' and says that it is very close to the Hashemia

Regarding the word isba', you're right the plural is asabi' but it is used in plural only when it follows numbers from 3-9 or 103-109 or 203-209 etc..
otherwise it is used in the singular form isba' (yes it is funny):
example: 27 isba' - 54 isba' - 6 asabi' - 109 asabi'

the relevant page is page3 in the manuscript (4 right in the pdf)
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[*] posted on 11-26-2007 at 03:52 PM


Just a tangent note,
the below page is from a manuscript in the museum of Sfax in Tunisia, I just thought it might be of interest, the pdf is very difficult to read due to the low quality.the author is Sheikh ?? alsafaxi and it is talking about oud making and tuning.
Anybody aware of this document ?
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[*] posted on 11-27-2007 at 07:45 AM


Many thanks ALAMI - what a good example of a clear document scan. I am now a bit out of my depth so will need to research a bit further before asking more questions.

Just for my information - I imagine that madmouma is plural of madmoum but how does it translate? Does it mean "double" or something similar - to make sense of the dimensions provided by Farmer?

I suppose if some units were reserved for early topographical measurement (or navigation perhaps) this might be the link to the metric scale - the metre being originally defined by triangulation surveys to determine the length of the meridian arc of the earth between the equator and North Pole - the metre being 1/10,000,000 of that distance? (Alternatively perhaps more accurate siderial measurement was used as the ancients were experts in that science?)

For information, I have updated my previous sketch comparing the profiles of the Maler lute and the Ibn Al-Tahhan oud to reflect doubling the distance of the bridge from the bottom of the bowl speculating that the original manuscript is in error. This gives a more satisfactory match than before in my opinion.
Also, it should be noted that the early Arabic writers, like Al-Khindi, and the authors of the 10th C Ikwan al-Safa and the Persian work Kanz al-tuhaf - according to Farmer's translation - gives some information about the proportional dimensions of an oud. This enables an albeit limited confirmation of the profiles of early ouds. For example that the depth of the bowl should be half the width and the length (of the bowl) should be 1 1/2 times the width with the neck length being 1/4 of the overall length. This latter ratio would fit the neck length proportions of the Doc's oud - sketch B in "Question - Big Ouds, Little Ouds" - but not the other two.



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[*] posted on 11-27-2007 at 10:58 AM


"madmouma" means with no space in between.
So if it is said 3 asabi' madmouma = 3 jointed fingers, touching each other.

the "Kabda" in the manuscript means fist and it equals 4 asabi' madmouma and I logically suppose that wherever a measure is mentioned in fingers as unit it means fingers "madmouma" otherwise it doesn't make sense.
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[*] posted on 11-27-2007 at 03:22 PM


Farmer records that the bridge location of the Ibn al-Tahhan oud is given as 2 asabi in the original manuscript (which Farmer notes as being "odd"). As asabi units can only follow numbers from 3 to 9 (and so on) then this would seem to be confirmation that the scribe had made an error of some kind in the original manuscript?
The current speculation is that the scribe likely meant 2 isba madmoum - equivalent to 9 cm metric?
Pretty complicated!!
Thanks ALAMI
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[*] posted on 3-4-2011 at 08:35 AM


What is wrong with this Oud?

The attached image is a scale drawing of an oud described by 14th C writer Ibn al-Tahhan al-Musiqi according to the translation/interpretation of the sole surviving manuscript by Dr H.G. Farmer.
Farmer was puzzled about the low placement of the bridge (which he thought odd) but was not otherwise concerned about the size of the oud which he described as being of "considerable dimensions" and a "real archlute". He was obviously not an oud or lute player!

It is not always clear and now impossible to determine - without access to the original manuscript - what Farmer has translated word for word from the original and what is his interpretation of the text.
Farmer gives Arabic linear measurements as 'isba' = 2.25 cm and 'isba madmum' = 4.5 cm as well as 'shibr' = 27 cm but does not give the source for these assumed metric equivalents. He then goes on to give the measurements of the oud in terms of 'asabi' and 'asabi madmuma' - presumably as written in the original manuscript(?). Farmer also (strangely) gives the neck length as "= 1 shibr + 1 'aqd" giving the metric equivalent as 29.25 cm - again without clarification - from which it might be assumed that 1 shibr = 12 isba and that the neck length is then equivalent to 13 isba.
Something is not quite right here!

More to follow.



Farmer Ibn al TahhanOud (587 x 805) (438 x 600).jpg - 63kB
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[*] posted on 3-4-2011 at 11:13 AM


Note that in creating the geometry of the oud according to the dimensions given I have assumed that the lower sound board profile below the widest point (the X axis) is a semi circle, that the upper sound board profile is described by a circular arc of radius R with its centre on the X axis, and that the width of the neck joint is 2 isba (or 4.5 cm using Farmer's metric equivalent). R in this case works out to be exactly 48 'asabi madmuma' units (or 96 'isba')

Curtis Bouterse, writing in The Galpin Society Journal #32, May 1979, proposes that the odd proportions of the oud are a result of scribal error - the scribe mixing up the 'isba' and 'isba madmum' in defining the length, width and bridge placement. This gives a more reasonable result proportionally but may not be the complete solution. Bouterse reasonably assumes that the lower sound board profile is a semi circle but makes no attempt to define a profile for the upper sound board. He also accepts Farmer's metric conversions for the linear units as well as the 'strange' neck dimension which, if valid, does not result in what turns out to be a more elegant solution to the final geometry (in my opinion).

Farmer assumes that 'aqd is a linear unit of measurement but what was his source? - he does not say.
ALAMI gives the meaning of 'aqd as 'knot' earlier in this thread. Several Arabic-English dictionaries give 'knot' as a definition as well as related meanings such as ' bound' or 'tied tightly' or 'knitted together' or 'joined' or 'a binding agreement or contract'. One sole dictionary source also includes 'inch' among these definitions.
So did Farmer or his linguist advisors know of some, now obscure, alternative definition of 'aqd - a linear measurement of value 2.25 cm or equivalent to an 'isba' unit? There may be one possibility.
More to follow.
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[*] posted on 3-5-2011 at 07:32 AM


Hey John, this oud-zilla cannot be real, we are getting something wrong!

May be when they used "asabi' madmouma" they were still counting in ones.
I mean that when they say 20 isba' madmouma they don't mean 20 X (4 fingers), they may be still mean 20 x one finger.

Another thing, the famous novel "Tom Thumb" is translated in French "Le petit poucet" and in Arabic "iqdat al isba'", literally the finger knot.

A finger knot in common spoken Arabic means the finger middle joint, what if the aqd is the upper half of the thumb? It is around 2.5 cm.

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[*] posted on 3-5-2011 at 08:11 AM


Thanks ALAMI. Interesting as my thumb measures pretty close to 2.3 cm at the middle joint so perhaps this is the answer to Farmer's source of unit size?

My proposed solution follows a more complicated argument and - with no knowledge of Arabic on my part - may turn out to be completely invalid. Nevertheless, let's go through the arguments just to see where it might lead.

OK, OK! to avoid confusion due to potential problems in interpretation/comprehension I shall now stick to the term 'finger' unit as the basic unit of linear measurement this being the width of a finger at the middle joint (but not including the thumb). So, for example an 'isba' will be one finger unit, an 'isba madmouma' will be 2 finger units, 8 'asabi' will be 8 finger units, 20 'isba' will be 20 finger units ... and so on.

On my hand, four fingers (madmouma) measures 7.5 cm across giving an average value of 1.875 cm for a finger unit - this value, as it happens, agrees with the 'standard' finger unit of ancient times it would seem.

Next - all about early Arab navigators.
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[*] posted on 3-6-2011 at 06:25 AM


Ancient Arab and Persian Navigators
The scientists of the ancient civilisations of the Middle East were expert astronomers using their observations to develop a sophisticated analogue computer - the astrolabe - to solve problems in spherical astronomy that was used, among other things, for precise navigation. The astrolabe had to be held steady for readings to be taken so was difficult to use on board ship when at sea.

According to researchers studying early navigation methods, the ancient Arab seafarers used a technique known as latitude sailing in the Northern Hemisphere. They would sail North (or South) until they reached a required latitude and then sail East (or West) maintaining this latitude until arriving at their destination.
A latitude bearing was determined, indirectly, by estimating the angle of elevation of the Pole star above the horizon using a hand held at arm's length and counting the number of finger widths that the Pole star appeared to be above the horizon. At the equator the Pole star appears to touch the horizon (zero degrees elevation or 0 degrees latitude) whereas at the North Pole the star appears directly overhead (90 degrees elevation or 90 degrees latitude). The researchers have found that one finger unit (i.e. finger width) measured 1.875 cm subtending an angle of elevation of 1 degree 36 minutes or very close to 1.5 degrees. They also found that the physical differences between individuals - long/short arms and thin/thick fingers - tend to cancel out to produce a uniform measure.
The attached image shows a hand being used to estimate the Pole star elevation in 'fingers' - in this example measuring an elevation of 8 finger units, equivalent to 12 degrees which is the latitude bearing. So a dhow sailing to the East from the Gulf of Aden and maintaining this latitude across the Arabian Sea would eventually make land fall on the West coast of India.

Next - a more accurate and consistent way to determine latitude using 'knots'.



Latitude by Fingers (506 x 600) (380 x 450).jpg - 36kB
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[*] posted on 3-6-2011 at 01:11 PM


The Kamal or 'Guide'

According to researchers into early navigation techniques a Kamal consists of a 'sighting plate' - a small rectangle of wood or bone, measuring "about 1 inch by 2 inches" with a string attached to its centre. The string is knotted at different points along its length.

The Kamal is used to determine latitude, the sighting plate taking the place of the fingers and a knot in the string held in the teeth until the bottom of the plate appears to align with the horizon and the top of the plate with the Pole star. According to one researcher, the string on a Kamal was calibrated so that the knots on the string were spaced at intervals equivalent to an 'isba' (the width of a finger or
1 degree 3 minutes angle of altitude) with markings from 1 to 16 'isba'.

There are a number of surviving examples of Kamel in museums.
The attached image is a replica that I made with knots spaced in 'isba' units (calculated using basic trigonometry). I was only able to tie 10 knots on the string before the knot spacing became too small to be practical. Another limitation is that as the sighting plate is held closer to the eye of the observer it becomes more difficult to focus clearly on the edges of the plate as well as the horizon and Pole star - especially for us older guys with less than perfect vision.

The seafarers likely had a collection of Kamel - each dedicated to locating the latitude of a particular place - a knot tied in the string at the correct position after taking a latitude reading before leaving the home port and on arrival at the required destination.

So what has this got to do with this investigation into the
14th C Ibn al-Tahhan oud?
Well, Farmer - as previously mentioned - mysteriously refers to the Arabic word 'aqd' as a unit of linear measure equal to the length (2.25 cm) that he reckons is equivalent to a 'finger' unit (in this case an 'isba') - yet 'aqd' means 'knot'. Could it be, therefore, that Farmer is using his (or the original scribe's) interpretation of 'aqd' based upon - perhaps - a now obsolete Arab nautical term where a 'knot' on a Kamel string means
1 'isba'? Now impossible to know for sure.









Kamal (600 x 559) (450 x 419).jpg - 24kB Kamal schematic (775 x 378) (600 x 293).jpg - 37kB
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[*] posted on 3-7-2011 at 11:46 AM


Interesting to note that the Romans considered an inch to be the width of a thumb whereas the rest of the ancient world used the width of a finger. A Roman foot was equivalent to 29.6 cm (80:81 of an Egyptian foot of 30 cm) and it was divided into 12 'inches' equal to 2.46 cm.
So this presumably is the origin of ALAMI's thumb 'knot'.

However, I do not intuitively believe that 'aqd' in the Ibn al-Tahan manuscript refers to a linear measurement. After all why would the scribe when recording measurements (albeit in error) in the standard units of 'isba', 'isba madmoum' and 'shibr' suddenly decide to introduce another, more obscure, unit of measure? It just doesn't make sense.
Although the original manuscript copy would need to be re-examined to verify this - I suspect that 'aqd, used in this context, means the point at which the neck joins with the bowl i.e. the neck joint - emphasising that the length of the finger board (1 'shibr' or 12 'isba') terminates at the neck joint.

Let's see how this concept works in practice with the proposed corrected dimensions and geometry.
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[*] posted on 3-7-2011 at 12:21 PM


The Revised Ibn al-Tahhan Geometry

The attached image is the proposed geometry of the Ibn al-Tahan oud - drawn to scale in 'finger' units - according to the corrected dimensions proposed by Curtis Bouterse and my proposed upper sound board profile, revised neck length. and assumed neck joint width of 2 'finger' units.

With the shorter neck length of 12 'finger' units (as opposed to 13 'finger' units given by Farmer) it can be seen that the neck length is then 1/3 of the string length which is the classic proportion found on ouds to this day. The radius of the arc describing the upper sound board profile increases from R = 29 'finger' units to R = 32 'finger' units. The significance of R = 32 'finger' units will become more apparent later.
It is useful, for purposes of comparison between oud/lute geometric profiles to express R in non dimensional (ND) units where the width of a sound board is divided into 4 equal parts. In this case each part is 4 'finger' units and R becomes 32/4 or 8 in ND units.

Another point to note is that if Farmer's value of 'finger' unit, equal to 2.25 cm, is applied the string length becomes 81 cm. Ibn al-Tahhan mentions that he no longer used frets on his oud which implies that a finger unit of 2.25 cm is incorrect the string length of 81 cm being practically unmanageable for a fretless oud - or even for one that is fretted.
On the other hand using a 'finger' unit of value
1.875 cm gives a string length of 67.5 cm - another significant measurement as it turns out.




Ibn al-Tahhan Finger (500 x 690).jpg - 80kB
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