Hi,
what is the diameter of an oud rosette?
I have seen some are larger than others.
Is there a standard size?
Thank youjdowning - 11-6-2015 at 04:43 PM
No - if properly designed to take advantage of the air resonance phenomenon (Helmholtz effect) - so helping to reinforce certain chosen bass
resonances of the instrument - the sound hole diameter(s) are largely defined by the air volume of the bowl.
Thank you jdowning appreciate your help , I will see the link.
Maybe there is some range to the diameter on the arabic ouds, from 10cm to 12cm.jdowning - 11-7-2015 at 02:57 PM
I do not know of any comprehensive survey that might confirm a sound hole diameter range for arabic style ouds.nasir - 11-7-2015 at 04:50 PM
Thank you, the link is good and has good information.Alfaraby - 11-7-2015 at 05:08 PM
I do not know of any comprehensive survey that might confirm a sound hole diameter range for arabic style ouds.
Well, from hundred of ouds I've checked, it seems that the most "common" diameter of the big soundhole is 108-110 mm.
I'm not sure if this is based on some scientific calculations, but most of the ouds I've encountered had had this diameter.
Some food for thoughts
Yours indeed
Alfaraby jdowning - 11-8-2015 at 05:39 AM
Food for thought indeed.
If the measured diameter of the sound holes of hundreds of arabic style ouds varies between 10.8 cm to 11.0 cm that means that there is only a
dimensional 1% variation (i.e. average 10.9cm ± 0.1cm) in sound hole diameter which I find truly astonishing and ,therefore, imagine is of
statistical significance. It is about as 'standard' as it gets.
This topic has been raised by nasir because he has observed a noticeable difference in the sound hole dimensions of arabic style ouds that must surely
cover a range greater than the above?
The only oud that I have to hand has a main sound hole that measures 11.3cm to 11.5cm in diameter (i.e. average 11.4cm± 0.1cm). The original string
length of this oud is estimated to be 62.5cm. So this sound hole is outside of the range of measurements recorded by Jamil. See attached images.
Perhaps this is not an arabic style oud (I bought it when living and working in Cairo in 1964)? It is a triple sound hole model just to complicate
matters.
This then begs the question 'what defines an arabic style oud dimensionally'? Is it just any oud that is not Turkish style (however that may be
defined). Is it just string length (so dictating instrument tonal pitch and tuning), sound board width, where it was made or what?
If oud makers traditionally choose a standardised sound hole diameter of 10.9cm±0.1cm tolerance regardless of 'arabic oud' instrument geometry
variation - that I assume, from my observations, may be quite significant instrument to instrument - then this may be a very interesting and important
piece of information about oud design practice.
Do other members have any data to offer concerning sound hole diameters of 'arabic ouds'? What do our oud makers have to say on this matter? How do
they determine sound hole diameter - by calculation or by simply copying what others have done before them?
[file]37350[/file] [file]37352[/file]Jason - 11-8-2015 at 07:24 AM
I think you'll find there is no real "standard" in Arabic oud dimensions. The dimensions can vary wildly between makers and geographical areas.
There tends to be quite a bit of variation, not unlike double basses made in the 19th century.jdowning - 11-8-2015 at 10:12 AM
That has been my impression. However, if the dimensions can vary wildly are the sound hole diameters always a standard 10.9cm±0.1 cm regardless?
So what defines an 'arabic' oud?Jason - 11-8-2015 at 12:20 PM
When asking what defines an arabic oud you'll probably get as many different answers as people you ask. Kind of like asking 'what is a jazz
guitar?'... there are a few accepted general characteristics but then again plenty of people play jazz on telecasters which don't fit the mold at all.
I think you might have more luck breaking it down a little further and asking "What are the typical dimensions of an oud built in Cairo?" versus
"What are the typical dimensions of an oud built in Iraq?" With the advent of the internet and the sharing of regional influence in luthiery maybe
that wouldn't even yield much in the way of solid data though.
It would be interesting to ask some of the well known luthiers on the forum how they go about deciding on sound hole size.
Personally, for me, an "arabic oud" is more about the style being played than the instrument itself. But obviously some instrument work better for
that style, and around we go :pAlfaraby - 11-8-2015 at 03:08 PM
I have skipped a very important characteristic of the ouds I referred to when I quoted 108-110 mm rosettes: 3 sound holes.
In one sound hole ouds, there were also 115, 120 mm, never seen more.
I asked master luthier Kamil Mowais about this and he said: we must compensate the lack of the two small holes by enlarging the only one we have.
I shall relate to the other questions later on.
Yours indeed
Alfaraby nasir - 11-9-2015 at 07:28 AM
Thank you everybody,
jdowning
Alfaraby
Jason
That was a good discussion, I learned from it.
My observations were based on syrian ouds, I have seen lot of syrian ouds,
just recently I measured the diameter of some small sample.
Maybe from now on I will measure every rosette I come by.
I noticed on the old syrian ouds the rosette is large about 12 cm, on the newer ones about 10 cm, still the sample is very small. jdowning - 11-9-2015 at 08:18 AM
It is an interesting topic but data is difficult to come by - not just sound hole diameter but the more difficult to measure bowl volume etc that
relate to calculated values of air resonance frequencies. In this respect, the single sound hole arrangement is better understood physically than
three sound holes where diameter and relative geometry of the sound holes makes a difference. Experimental data, such as it currently is, suggests
that triple sound hole arrangements may not be treated as additive - dependant upon how closely positioned the sound holes are to one another i.e. it
may not be valid to combine together the areas of the individual sound holes to arrive at an equivalent single sound hole diameter used to determine
the calculated air resonance frequency.
Note that in his book 'The Oud Construction and Repair' Richard Hankey provides a design based upon a Syrian Nahat oud made in 1910. The single sound
hole is given as 11.6 cm diameter so that is within the 10cm to 12 cm range currently proposed.
