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jdowning
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For information.
The Ikhwan al-Safa give the relative and perfect Universal proportions of the human body as found in a new born child including (among other
proportions):
The height is 8 units as is the length fingertip to fingertip with arms out stretched. Finger tip to elbow is given as 2 units (i.e. a cubit) as are
the lengths - soles of feet to kneecap, kneecap to groin, groin to top of heart, top of heart to top of head.
The basic unit of measure is a 'hand span' (tip of thumb to tip of little finger with fingers fully extended). This is equivalent to half a cubit
measure.
Interestingly, Leonardo da Vinci's drawing of 'Vitruvian man' dated 1490 (derived from dimensions given by Roman architect Vitruvius) gives identical
proportions - see attached image.
So a cubit measure is a quarter of the height of man in the Universal harmony equation according to the cosmologist and numerologist beliefs of the
ancients.
Of course, the physical measurements of a human being vary - hence the variablity of the ancient metrical standards. The cubit standards (particularly
the Royal cubit) may, perhaps, have once been based upon the physical dimensions of a king, Pharoe, Shah or other ruling earth bound 'deity' - those
of unusual 'kingly' stature standing 'head and shoulders' above the average person in height.
So, the ancient Egyptian common cubit measuring 447 mm equates to a height of 1.79 metres (5ft 10 inches) compared to the Egyptian Royal cubit of 525
mm equating to a height of 2.10 metres (6ft 11 inches) or the Persian Royal cubit of 640 mm equating to a man's height of 2.56 metres(8ft 5
inches)!
[file]26638[/file]
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jdowning
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I have revised the previously posted image of the proposed Ikhwan al-Safa oud geometry to show that if the arc describing the upper sound board
profile is extended beyond the neck joint it intersects the vertical centre line at a distance 7 finger units from the nut (or 1/4 string length of a
28 finger unit length string).
This is interesting because it so happens that this is the position of the last fret on the fingerboard (the 'little finger' fret - equivalent to the
fifth fret on the European lute) as defined by the Ikhwan al-Safa i.e. "attached at the three quarter point of the string towards the neck".
Most (but not all) ancient cubit measures may be divided into 24 finger units (small or common size) or 28 finger units (Royal or large size). It
would seem that the so called Arabic 'black' cubit most likely measures 24 finger units (as assumed here) - based on a proposal that 'black' may have
been derived from Aramaic meaning 'small'.
This assumption is further confirmed by M. Ismail Marcinkowski ('Measures and Weights in the Islamic World', I.A.I.S) who states that the measure
'Qabdah' of four finger units is the equivalent of 9 cm in the 'black' cubit system - i.e. 1 finger measures 2.25 cm.
Of course, other ancient standard finger unit sizes (ranging from 1.85 cm to 2.28 cm) might also be assumed to give alternative string lengths
(ranging from about 52 cm to 64 cm) - or just select a suitable string length - the proportions of the oud remain the same either way.
So, for example, for a 60 cm string length the finger unit size would be 60/28 = 2.14 cm and sound board width would be 16 X 2.14 = 34.2 cm etc. It so
happens that the width of my index finger (measured just below the nail) is about 2.1 cm and I am comfortable with a 60 cm lute string length. Just
coincidental perhaps?
[file]26647[/file]
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jdowning
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For information, the attached schematic represents the fret positions on the oud defined by the Ikhwan al- Safa - derived from divisions of the string
length. The diagram should be self explanatory.
Note that there are only four frets (matching four fingers of the hand). The scale spacing is Pythagorean with a full tone at fret #1.
No intermediate frets are specified as described by contemporaries Al-Kindi (9th C) and Al-Farabi (10th C).
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jdowning
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Note that the Ikhwan al-Safa make no mention of a sound hole, its diameter or position ( if indeed there ever was a sound hole on a 10th C oud) or
the position of the bridge. The geometry of these two components has here been based upon the proportions of the surviving late 19th C Al-Arja oud
(owned by forum member ALAMI) that has a similar geometry as reported earlier in this thread.
Oddly enough, the Brethren - given their interest in numerology, geometry and proportions - make no mention of sound board bracing. All that they say
is that the sound board (open to dispute) should be made from a thin, hard and light wood - that rings when struck. But how thin is thin? Early four
course guitars and five course vihuelas (from the Iberian Peninula - Moorish influenced?) were made with only two braces on each side of the sound
hole - the sound board being made of sufficient thickness to support the string tension. Is this how it was for the 10th C oud with only four strings?
Or was the Ikhwan al-Safa oud sound board made a bit thinner like later ouds (and lutes) so requiring the support of cross bracing? We can never know
the answer, of course, but if the latter case applies perhaps the Al-Arja oud bracing geometry might be a reasonable guess at what might have been?
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jdowning
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To dwell a bit more on the question of ancient measurements and their metric (or Imperial) equivalents.
In the absence of a standard measuring rod giving the size (for a particular time and society in the past) of a cubit, hand span, finger or what have
you - it was common trade practice to simply use the actual dimension of the appropriate part of the body as the unit. So the cubit (for a particular
person) was measured from elbow to tip of the outstretched fingers, hand span from tip of thumb to tip of little finger - fingers fully spread and so
on.
I recall as a child seeing vendors of cloth in open markets quickly (and not very accurately!) measuring a 'yard' length (or two cubits equivalent)
from finger tip to middle of the chest with arm fully out stretched - no doubt a common practice even today.
For a 'finger' unit, however, where is the width of the finger measured - at the first or second knuckle joint or some other place - and what finger
is measured index, ring, middle?
To date, I have come across only one early reference indicating the point where a finger width is measured. 'An Early 17th C Ottoman Treatise on
Architecture' (Riale-i Mi'mariyye) - a Turkish/English translation by Ca'fir Efendi and Howard Crane - gives the measuring point as the width of the
index finger measured just below the fingernail of the index finger that is pressed onto a flat surface.
As previously mentioned in this thread, in my case that measure is about 20.8 mm (as is the width at the first knuckle - more accurately measured with
calipers). Applying this to the design of the Ikhwan al-Safa oud of string length 28 fingers gives a string length of 58.24 cm (close to the string
length of a Turkish oud today). Although not quite comparable I play a lute with string length 60 cm that I find a bit of a stretch at times so 58 cm
or so string length may well be the optimum length for a person of my particular physique?
[file]26705[/file] [file]26707[/file]
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jdowning
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I have just received a copy of 'The Epistle on Music of the Ikhwan al-Safa' by Prof. Amnon Shiloah, Faculty of Fine Arts, Tel-Aviv University, 1978 -
through the Canadian Inter Library loan system (many thanks to the Jewish Public Library of Montreal, Quebec for the loan).
First impression is that the book is written (wonderfully!) in plain English (unlike the Owen Wright version that, frustratingly - in parts - requires
the aid of an Oxford English Dictionary for comprehension!).
There appears to be - not surprisingly - some differences in the independant translations between the two works so it will be interesting to
eventually make a full comparison. No major conflicts of interpretation, however, are anticipated but - if there are - this will be reported here at a
later date.
It is unfortunate that this publication is now out of print. It was produced at low cost but, nevertheless, well made with hard covers and substantial
'lay flat' binding - costing, until recently, between about $6 to $12 new 'on-line'.
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jdowning
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So far this thread has focussed mainly on the sound board geometry of ouds and lutes which, of course is not the whole story. Now to look at the bowl
geometry.
From the earliest accounts concerning the oud it is assumed that given the depth of the bowl is half the width of the soundboard that the cross
section of an oud bowl should be perfectly semicircular throughout the length of a bowl.
Surviving lutes are rarely symmetrical. Even if the bowl section is semicircular (or close to it) the longitudinal section may not follow the geometry
of the sound board profile. Lute bowls - particularly of the larger examples - were often flattend in section - until the late 17th/ 18th C when the
bowl design became deeper relative to the sound board profile.
The same bowl geometry variations may also have applied historically to the oud.
A familiar example already discussed on this thread is the old Egyptian oud # 0164 in the Brussels Musical Instrument Museum. The attached images
(including an image overlay) confirm that the longitudinal profile of this oud does not match the profile of the sound board - it is deeper in cross
section and asymmetrical in longitudinal cross section.
Deeper bowl sections are structurally stiffer (more resistant to bending than shallower sections - particulary at the neck block) and have greater air
volume so favouring bass response (Helmholtz effect).
[file]27493[/file] [file]27495[/file]
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jdowning
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The old Egyptian oud that I own and that is (still!) undergoing restoration is another example of a bowl that is asymmetric and deeper than it is
wide.
The attached image shows the geometry of the bowl drawn from interior measurement so represents the mold geometry of the bowl.
Both this oud and the Brussels #0164 - each multi-ribbed construction with ribs of equal width - were assembled on solid molds. Both bowls show a
construction 'fault' where the luthiers failed to make the outer ribs wider than the rest at the outset - so they ended up being too narrow.
[file]27497[/file] [file]27499[/file]
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jdowning
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Using several circular card templates to judge the internal cross section of the Holmy oud the original mold was semicircular (or quite close) so that
the additional depth was created by the width of the outer ribs. It can be seen from the image of the end of the bowl that all of the ribs converge to
a point except for the outer ribs that join in a vertical line.
Richard Hankey in his book "The Oud Construction and Repair" describes a bowl geometry for a contruction based upon a Syrian Nahat oud circa 1910. The
bowl is semicircular in section (with ribs of equal width and geometry - so allowing free form assembly without a mold provided each rib is made
identical) but with significantly wider top (outer) ribs that add the required additional depth to the bowl. The outer ribs are joined at the tail
block in a vertical line - the tail block being made deeper than semicircular to accommodate the additional depth. If this method of bowl construction
is historically representative of an early 20th C oud (Syrian Nahats at least) then it is interesting to find a similar construction in the bowls of
some surviving 18th C lutes by some of the German luthiers.
More to follow.
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Ronny Andersson
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Have you seen this one? http://www.pamelasmusic.co.uk/images/Forsale/string/mandolins/L113....
Best wishes
Ronny
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jdowning
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No - but it reminds me of a version of the Algerian Kuitra (straight pegbox, 'cut in' rosette, and 'box' shaped bowl, leather binding around
soundboard edge) - except that it has 5 courses and frets and an atypical bridge (not made like a moustache). Possibly purchased by a European tourist
in the late 19th/early 20th C who may have added the frets to play it as a 'lute' - or perhaps in order to sell it as an old European lute to the
unwary collector?
Apparently the Kuitra has never truly been adopted by Tunisian musicians - so is presumably regarded as a folk instrument. Some are finely made by
professional luthiers others appear to be 'home made' by amateurs. Smaller versions (al-qrinda and al- qria) it seems had the bowls made from a
vegetable gourd (hence the 'funny' shape of the bowl?)
This informative site deals in detail with the traditional Algerian instruments, their music, tuning, musical theory etc including images and
information about the Kuitra.
http://diapasondeskikda.blogspot.ca/
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jdowning
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Some of the early European lutes with the narrow shouldered 'almond shaped' geometry by Laux Maler and Hans Frei (see page 2 of this thread) survive
because they were much sought after by the French during the 17th C for conversion to 11 course lutes.
By the end of the 17th C and early 18th the manufacture of 11 course lutes had switched to Germany. The German makers followed the acoustically
successful geometry of 6 course lutes by the early luthiers like Maler and Frei but increased the bowl volumes by adding depth presumably to favour
overall bass response due to the additional bass courses.
I have examined full sized drawings on file of four of this style of German lute (measured and drawn from the original instruments by luthiers Stephen
and Miranda Murphy, 1975). All of the bowl sections (given some slight asymmetry) appear to be very close to semicircular in section with additional
depth added - to make the section deeper than it is wide.
As an example, the attached image is the half section of a bowl drawn full scale at the point of maximum width of the soundboard of an 11 course lute
by Johann Christian Hoffman. Leipzig, 1716 in the Brussels M.I.M. # 1559.
The other examples examined showing similar geometry are lutes by:
- Martin Hoffman, Leipzig 169..., Nürnberg Germanisches National Museum # MI245
- Joachim Tielke, Hamburg, 1696 # MI 394 in the N.G.N.M. collection.
- Wiegert Linz, 17 ... # MIR 898 in the N.G.N.M. collection.
All of the lute bowls examined are wide ribbed with 9 ribs per bowl.
The additional depth appears to be related to bowl size - the Christian Hofmann example being the largest of the four with an added depth of about 25
mm - the smaller bowled instruments having less additional depth than this.
Note that the significant natural 'cupping' or fluting of the wide ribs has not been represented in the attached drawing.
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jdowning
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There are some nice images of the J.C. Hoffman lute, #1559 in Robert Lundberg's 'Historical Lute Construction'. The chapter on 'The Bowl' also
discusses and illustrates, with some historical examples, variations in bowl geometry of lutes. I shall cover some of the same ground with data from
other sources.
I have traced the outlines of the soundboard and bowl from the Lundberg Hoffman lute images to create the attached overlay sketch - to show how bowl
depth varies with soundboard width. Not high precision but close enough to give a good idea for sake of comparison.
From the other examples examined of this type of lute previously mentioned, this soundboard/bowl profile geometry would appear to be typical,
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jdowning
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The late 17th/ early 18th C German lute makers based their soundboard/bowl geometries on the early almond shaped, 6 course, 16th C Italian lutes (by
German makers such as Maler and Frei) - because their particular geometry and bowl air volume worked well acoustically for conversion to 11 course
lutes during the 17th C.
Here for comparison is an overlay drawing, to scale, of a lute by Hans Frei, Bologna, c. 1550 and a sketch of the bowl cross section measured at the
front edge of the neck block (significant natural fluting of the ribs has not been represented for clarity). Note that the section of the upper half
of the bowl is deeper than half the sound board width whereas for the lower part of the bowl the depth is equal to half the sound board width.
However, the bowl section is not semicircular but egg or ellipse shaped except at the upper part of the bowl where the section is close to
semicircular with extra depth added. This geometry provides more air volume to the bowl than can be achieved with a perfectly semicircular bowl
section (and is structurally stiffer in the region of the neck block).
Some of the 18th C German luthiers, using a similar soundboard profile, retained the same bowl volume with a simpler bowl cross section geometry - i.e
semicircular with extra depth added.
This example of a lute by Hans Frei (#67/1965 in the Warwick County Museum, England) is an example of this style of lute later converted during the
17th C to an 11 course instrument with wider replacement neck and pegbox.
[file]27609[/file]
[file]27722[/file]
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jdowning
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To further demonstrate the relative complexity of the 'Warwick Frei' lute bowl geometry, here is a 1/2 section of the bowl at the maximum soundboard
width.
It can be seen that the bowl section changes from a semicircle plus extra depth at the neck block to an oval (height equal to 1/2 sound board width)
at the widest part of the soundboard.
So the upper part of the bowl section is semicircular with extra depth - the extra depth diminishing from about 12.5 mm (1/2 inch) to around zero at
the widest part of the soundboard.
The lower part of the bowl section then changes (it is proposed) to an oval geometry created from 3 conjunct arcs R1, R2, and R3 with centres A1, A2,
A3 located on the circumference of a circle of radius 1/8 sound board width with centre at A (mid point of soundboard width).
It can be seen that a semicircular arc BB with centre at A falls far short of the bowl profile at this point - the consequence of the oval geometry
being to create additional air space.
The complexity of the bowl geometry means that the bowl must have been constructed using a solid mold - carved first 'in the round' (using geometry
created templates of the bowl section) and then carved with 'flats' to accomodate the 11 rib positions.
The 18th C German makers seem to have replicated the bowl volume of these desirable early lutes using a simpler semicircular section throughout with
extra depth.
[file]27720[/file]
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jdowning
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The longitudinal profile of the Warwick Frei bowl may have been developed directly from the sound board profile as shown in the attached sketch (not
drawn to scale for clarity).
At the neck joint an extra depth of 1/2 inch (or about 12.5 mm by whatever standard of mid 16th C Italy - but close to modern standard however) is
added to the depth of the semicircular bowl section. A line drawn from this point to the bottom of the bowl provides a measure of the extra depth of
the bowl cross section for any position up to the widest part of the soundboard (the cross hatched area of the sketch). This extra depth diminishes to
around zero at the sound board widest point (after deduction of the soundboard thickness).
The attached image shows the Warwick Frei lute as it survives today - altered from its original condition, by re-necking to an 11 course lute during
the 17th C.
Next to examine the geometry of another surviving Frei lute that is different from the above instrument - perhaps a later development by this maker.
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jdowning
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Next to examine the bowl geometry of another lute by Hans Frei - # C34 in the Kunsthistorisches Museum, Vienna. As far as I know none of the survining
lutes with a Frei label carry a date so a date of 'circa 1550' is assumed.
Some nice photos of this particular instrument can be found in the book 'Historical Lute Construction' by the late Robert Lundberg - but there is no
information provided about the bowl geometry.
Working from a full sized drawing of the lute made by luthier Stephen Murphy in 1975, it is apparent that the bowl geometry is quite different from
the 'Warwick Frei' lute previously posted - almost the reverse concerning the bowl cross section geometry.
Here the bowl section is semicircular but partly cut away in depth resulting in a flattened bowl section - the longitudinal profile otherwise
matching the sound board profile. It is proposed here that the depth reduction for any section of the bowl is determined by drawing a line from the
neck joint to an offset of about 1/2 inch at the bottom of the soundboard (shown cross hatched in the attached sketch).
This style of flattened bowl section would appear to predate bowl sections of Italian lutes of the late 16th C so may be a transitional design by Frei
- assuming of course that this lute was made by Frei (can't always trust the labels)?
There is another lute in the Vienna collection by Hans Frei (I do not have the catalogue number). From Stephen Murphy's full size drawing of the lute
the bowl cross section and longitudinal profile geometry would appear to be close to that of the 'Warwick Frei' lute previously posted.
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jdowning
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It is perhaps worth noting that Lundberg in his book on lute construction incorrectly states on page 19 - with reference to a Frei lute - that Fig 1
(on page 18) shows the cross section of an 11 rib lute by Hans Frei, "also shown in Photo 1".
The cross section in Fig 1 appears to be that of the 'Warwick' Frei lute whereas the Frei lute shown in photo 1 is the #C34 lute in the
Kunsthistorisches Museum, Vienna. As previously posted the bowl cross and longitudinal sections of these two lutes is significantly different.
Next - for comparison - to examine the bowl geometries of two surviving early 16th C lutes by Laux Maler #655 1931D and #65 1408E in the National
museum, Prague.
The Maler lute geometries are of particular interest as they appear to be closely related to the soundboard profile of an oud described by Ibn al
Tahhan in the 14th C. (See page 2 of this thread)
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jdowning
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Lute 651408E by Laux Maler has been converted during the 17th C from its original 5 or 6 course state to an 11 course instrument by replacement of the
neck. The additional extra width of the fingerboard at the neck joint (without increasing the depth of the neck) being achieved by re-cutting the neck
block joint to a shallower angle (relative to the fingerboard surface).
Referencing a full size drawing of the instrument by luthier Stephen Murphy that shows the sound board profile of the lute, the longitudinal bowl
section as well as two cross sections of the bowl - the attached images indicate that the bowl has a slightly flattened semicircular cross section -
similar to the Frei #C34 lute geometry previously posted.
Note that there is no perfect symmetry of the bowl due perhaps to slight distortion of the original bowl geometry over time following
repairs/modifications etc.
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jdowning
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The full size drawing of the Laux Maler lute in the Prague National Museum # 655 1931 that I have on file appears to have a draughting error but I
shall post the results nevertheless for information. The drawing shows two bowl sections - one at the widest point of the soundboard and the other at
the soundhole centre - and a bowl longitudinal profile. Unfortunately, the bowl section drawn at the rose centre does not match (in height) the drawn
longitudinal profile of the bowl. As the bowl sections appear to be semicircular - modified with additional height (max. soundboard width section)
and height reduction at the soundhole centre (see attached sketches drawn to scale) I have adjusted the bowl longitudinal profile accordingly assuming
the sound hole centre bowl section has the offset shown.
I do not have full frontal and side images of this lute to verify these assumptions so these would have to be independently checked out. However, the
soundboard profile relative to bowl longitudinal profile appears to be close to the Vienna #C34 Frei lute previously reported.
Precise measurement of a surviving lute or oud (from first hand experience!) is a time consuming process. Capturing the sound board profile accurately
is straightforward enough - just (carefully!) trace around the instrument inverted on a sheet of card. Determination of the bowl geometry is another
matter and requires an apparatus that will allow plotting of the bowl surface in 3D - a relatively simple apparatus to design but a time consuming
procedure to execute and record the data. Usually, however, time is of the essence when it comes to measuring museum artifacts and in the rush to
record information errors can be made or important measurements missed - the omissions only discovered at a later date (but too late) when trying to
create a drawing from the recorded data.
Just to complicate matters, most if not all of the surviving instruments are rarely of perfectly symmetrical geometry (if they ever were in the first
place).
What is interesting - for the earliest surviving lute bowls at least - is that the bowl sections (if correctly represented in a drawing) appear to be
based on a semicircle with extra depth added to increase the bowl depth or subtracted to produced a more 'flattened' section (the 'Warwick' Frei lute
composite profile, previously reported, not withstanding).
However, lots of scope for error - so beware!
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jdowning
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According to G.H.Farmer, translation of surviving manuscript fragments by Al-Kindi (died ca 874) reveals that the depth of (the bowl) of an oud should
be half the maximum width of the soundboard. In the 10th C, the Ikhwan al-Safa state that the depth (of the bowl) of an oud should be half the width
(of the soundboard).
The difference between these two statements is that Al-Kindi apparently refers only to the bowl depth at the maximum point in soundboard width whereas
the Ikhwan al-Safa seem to imply that the depth of a bowl section at any point along the length of a bowl should be half the soundboard width. But,
according to Al-Kindi, the bowl depth at any other point other than maximum soundboard width might not be half the soundboard width .
The general assumption also is that the bowl section should, therefore, be a semicircle of radius half the soundboard width - although this (perhaps
reasonable assumption?) is not confirmed in any of the manuscripts as far as I am aware. However, as is evident in the 'Warwick' Frei lute bowl
section at maximum soundboard width (previously posted), just because the bowl depth is half the sound board width does not always mean that the
geometry of the bowl section must be a semicircle. In the case of the 'Warwick' Frei lute, neither does the bowl section at any other point conform to
a pure semicircular section (although semicircular plus additional depth) - so conforming to Al-Kindi?
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jdowning
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On the other hand, the earliest surviving manuscript source providing the cross section geometry of a lute bowl (Arnault de Zwolle. mid 15th C -
previously posted) indicates that the bowl cross section was a semicircle throughout the length of the bowl. However, as Arnault de Zwolle was
unlikely to have been a luthier, his drawing of a lute is likely to have been a compilation of information gleaned by talking to luthiers but without
a full understanding of the design tradition. Certainly his geometry of a lute appears in places to have been 'fudged' to fit the 'facts'. So, for
example, his statement that the diameter of the soundhole is 1/3 the width of the soundboard (measured though the soundhole centre) does not fit the
described geometrical construction.
So were the early oud bowls of the 10th C - as described by the Ikhwan al-Safa - semicircular in cross section throughout? I would speculate that they
were originally - based upon the overall proportions of an oud given by the Brethren (and the proposed geometry previously posted). However, by the
14th C the more elongated oud profiles described by Ibn al-Tahhan may not have conformed to this ideal semicircular cross section - perhaps in an
effort to maintain the same bowl air volume as that of the 'ideal' Ikhwan al-Safa oud geometry? Perhaps the 'Warwick' Frei lute bowl geometry then is
a reflection of the later Ibn al-Tahhan oud geometry development?
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jdowning
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As proposed earlier in this thread, Arnault de Zwolle appears to have been trying to show that lutes of the 15th C had an egg shaped profile. If so,
this design would appear to predate lute designs of the late 16th C (although these were longer in sound board profile). However, because no lutes of
this pattern have survived from the early 16th C or before does not, of course, mean that they did not exist alongside the almond shaped lutes by Frei
and Maler that have survived (because they were ideally suited for later conversion into 11 course Baroque period lutes).
Arnault de Zwolle describes a lute with a semicircular section bowl so it will be interesting to see if any of the late 16th C lutes were also made
with semi circular bowls sections (i.e. pure unmodified semicircular sections) - indicating a possible unbroken link to a much earlier design
tradition.
Robert Lundberg shows sketches of two late 16th C lute bowl sections by Wendelio Tieffenbrucker (Figs. 3 and 4, page 21 of his book) where the
sections at maximum sound board width appear to be very close to a semi circle (although there is no indication to confirm if the semicircular section
continues throughout the length of the bowls.
I have some full size drawings of some of the surviving lutes by W. Tieffenbrucker so will next check these to see if there are additional sections or
longitudinal bowl profiles drawn that might further clarify this question.
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jdowning
Oud Junkie
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First to examine the small descant lute #C39, by Wendelio Venere in the Kunsthistorische Museum, Vienna. This lute has seven courses with a string
length of 441 mm. date thought to be circa 1600.
The full size drawing that I have on file shows only one bowl section at the widest point of the sound board. Nevertheless, as the neck joint is drawn
in longitudinal section it is likely that the bowl section at this point is a complete semi circle. Not so, however, at the widest point of the bowl
where the section is a flattened semicircle of radius AB with centre at A offset by about 7mm - as shown in the attached image.
The proposed longitudinal profile of the bowl compared to the sound board profile is as shown in the attached image. Maximum offset at the clasp end
of the bowl is about 9 mm.
Here the flattening of the semicircular bowl section is similar to lute #C34 by Frei in the collection (previously posted).
Let's next look at another example by the same maker.
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jdowning
Oud Junkie
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A lute labelled "In Padova Wendelio Venere 1592" in the Bologna Academia Filarmonica, Italy has a string length of 58.3 cm.
A full scale drawing that I have on file of this instrument has two bowl sections drawn full size - one just below the maximum sound board width (at
the end of the clasp) and the other at the centre of the sound hole.
Both of the sections are very nearly a full semicircle in profile - only flattened by about 5 mm. There is no longitudinal profile of the bowl drawn
so it could be very close to the sound board half profile (as shown in the attached image)
Robert Lundberg gives a 'thumbnail' sketch of a bowl section of a lute by 'Wendelio Venere, Padua, 1592") (Fig 4, page 21 of his book) as well as a
'full frontal' photo of a lute by the same maker dated 1592 in the Academia Filarmonica, Bologna (page 8) - so this may be the same instrument under
examination here. If so, the bowl sections would appear to be in close agreement. On page 22, Fig 9 Lundberg also provides a sketch of a 'typical'
bowl longitudinal bowl profile of a Paduan style lute of the period which shows a slight flattening of the bowl section at and below the widest part
of the sound board as well as a slight deepening of the bowl section near the neck block. This would also be consistent with the bowl profiles given
in the attached images - the bowl profile matching the sound board profile at around mid length of the bowl.
So here is an example of a late 16th C lute that has - very nearly - a semicircular bowl section throughout its length, bearing in mind that most, if
not all surviving lutes have some slight geometrical asymmetry in construction be it in sound board profile or bowl sections.
Next to look at another example of a Venere lute bowl.
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