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I'm working out the design for this instrument I'm building for my wife's 50th birthday. It's a, well, I don't know what to call it. It will have 4 double courses, tuned like the top 4 strings of a guitar that's been hacked off at the 5th fret - GCEA. Each course will be a pair of identical strings, no octaves like on some double course instruments (unless I change my mind on that). The scale length is 18.66", which is what you get if you measure a 24.9" scale guitar from the 5th fret. I plan to string it with light or medium gauge guitar strings (two sets of the D, G, B, and hi E strings). So, the string tension will be like a 24.9" scale guitar.

Having never built a double-course instrument before, I'm looking for some guidance on string spacing and nut width. I don't even have much experience playing mandos or 12 string guitars.

First, I'm not sure how much space to put between the two strings in each pair. I would think the basic idea there is to put them as close together as you can without having them buzz against each other. That would seem to depend somewhat on string tension, which is why I gave you the info above. Second, I'm not sure how much space to put between the courses. I think I'd lean toward a medium to wide spacing, but I'm not sure what that might be on a double course instrument.

I've got some nut width info on mandolas, which are in the same ballpark as far as scale length goes. They seem to range from 1 1/4" to as much as 1 1/2" nut widths.

The only other info I found searching the archives here (I haven't searched other forums) - a chart that indicates spacing for a 12 string guitar at the nut: .1" between the two strings in each pair, .2" between courses. However, I would tend to think I'd want a bigger difference between the spacings within versus between courses.

Any helpful suggestions would be much appreciated.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Todd, This may not be much help to you, I suspect Dave with his guitar bazoukis would have a better idea. However on my lutes I use a 4.5mm gap between the strings in a pair at the treble end of the saddle increasing to 5.5mm between the pair at the bass. On the nut the figures are 2mm treble to 2.5mm bass. This is on a 595mm scale length.

ColinColin S38801.2675231481

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Todd,

Really it is all down to personal preference and what/how your wife likes to play. The Fylde and McIlroy bouzoukis I have are around 30 to 31mm at the nut which fits with your 1.25" mandolas. At the saddle string width (outside edge of outer string) varies from 46-56mm - but these are 25.5" scale length. Most people like this as they can play chordal stuff and if they are used to mandolins, melody stuff fits easily. I am at the "extreme", however, as I'm used to fingerstyle guitars and built my own guitar bouzouki with a 42mm nut with and 60mm saddle string spacing. Works for me.

As for the strings, allow your normal gap on a guitar for the outside two to the edge of the fingerboard, allow just over 2mm between the centre of the strings for the unwound unison pairs and 2.5mm for the wound ones; then depending on the nut size you have chosen, the rest follows from there.

I use the Stew Mac nut marking gauge tool to set the other strings spacings, but you could use equal distances between the pairs.

Sounds a fun instrument, keep us updated with progress and show us some pics.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

Todd, are you gonna do some inlaying on this instrument?

Sounds like a beautiful and challenging project, your wife will be really delighted when she receives it too i'm sure. Please keep us updated with pics throughout the build, i'm really curious about this project! Share the pleaure with us!

[QUOTE=Todd Rose] I'm working out the design for this instrument I'm building for my wife's 50th birthday. It's a, well, I don't know what to call it.

[/QUOTE]

mandorequintolele

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Jim Kirby
kirby@udel.edu

Todd,
This sounds like a fun project.
I have been building Mandoleles lately.
Just as you describe, with four double course steal strings. I went with a little over 20" scale though and figured string gages to tune it up to DGBE. Gages are 012, 017, 025b, 035b. (on the light side).
As far as string spacing, the first one was wide like a Uke but I brought it in thinner for the next two builds. I don't have the numbers with me for the nut end but the mesurment at the saddle is 45mm from the outside string centers. I personally like it on the wide side like Dave. It makes it easyer to play solos or single strings.
I tried a slimmer neck, more like an octave Mandolin, but it felt too narrow to me.
Good luck and show us some pics along the way.

Wade

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Wade
Nashua, NH
http://www.wadefx.com

Thanks to each of you for your replies.

Colin - I'm puzzled. It sounds like you're talking about the space between the two strings within a pair. But 5.5 mm seems like a very big space, even if you're measuring from string centers. Also, why would the space between two strings within a pair get wider from the nut to the saddle? I would think that that space would remain constant even as the space between courses gets wider toward the saddle. On the other hand, if you're actually talking about the space between courses, 2 mm at the nut is very small. I must be missing something.

Dave - How many courses do your "guitar bouzoukis" have?

Serge - My wife and I have similar aesthetic sensibilities. Ornate inlay, esp of pearl, abalone, etc, is something we admire but wouldn't choose on our own instruments. This instrument will be made of very fancy woods, but will otherwise (I hope) have an elegant simplicity.

Jim - Great name suggestion!

Wade - With a 20" scale, the string gauges you indicated, and tuned up to DGBE (low to high) that must give you very high string tension, right? Very stiff strings, similar to a mandolin, not a guitar? I do have some doubts about making my "mandorequintolele"    with string tension the same as a 24.9" scale guitar as I've planned. The idea is that it will have a sound more like a guitar, and that it will be easy to play. Also, being a flattop instrument with the strings anchored at the bridge (no tailpiece), I'm planning a soundboard that will be braced similarly to a flattop guitar, not extra-heavy bracing for 8 high-tension strings. Actually, I really don't know what it will sound like - it's an experiment. I figure it will sound cool no matter what. Anyway, I'm interested in whatever further thoughts you may have about string tension, scale length, and related issues, as they apply to double course instruments that dwell in the no-man's land between guitars and mandos (mandorequintobouzoukocitternoguitoleles). Are your mandoleles archtop?

Thanks again for the info, the interest, and the encouragement.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

[QUOTE=Todd Rose]
Dave - How many courses do your "guitar bouzoukis" have?

QUOTE]

Todd,

Four pairs normally, tuned GDAD or GDAE (or ADAD or .... you name it!!).

You can have five courses and then it becomes a Guitar-cittern or 5 course guitar-bouzouki. I'm currently making one of these.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

Thanks, Dave. Now, let me make sure I'm getting this right. You made your own four course guitar-bouzouki with a 60 mm total string spacing at the saddle, with 2-2.5 mm spacing between strings (measuring on center) in a pair. According to the sketch I've just done on some scratch paper, it looks like you've got about 15 mm between courses at the saddle, or almost 2 cm between the centers of the courses. Really?    

On a typical 6 string guitar with a 1 3/4" nut (common for a "fingerstyle guitar") and a 2 1/4" total string spacing at the saddle, there's only about 11-11.5 mm between the strings at the saddle.

Am I understanding you right?

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

[QUOTE=Todd Rose] Thanks, Dave. Now, let me make sure I'm getting this right. You made your own four course guitar-bouzouki with a 60 mm total string spacing at the saddle, with 2-2.5 mm spacing between strings (measuring on center) in a pair. According to the sketch I've just done on some scratch paper, it looks like you've got about 15 mm between courses at the saddle, or almost 2 cm between the centers of the courses. Really?    

On a typical 6 string guitar with a 1 3/4" nut (common for a "fingerstyle guitar") and a 2 1/4" total string spacing at the saddle, there's only about 11-11.5 mm between the strings at the saddle.

Am I understanding you right? [/QUOTE]

Todd,

Yes that's right, there is 14-15mm between each string pair at the saddle (measured between the closest strings) and 20mm between the centres of the string pairs. As I say it works for me. I was just trying to show that these things should be down to personal choice/playing style and not set formulas.

A 1 3/4" nut width may be "typical" of fingerstyle guitars but 44.5mm nut width is way too much on the small side for me for fingerstyle. I now use 46mm (1 13/16") as my standard nut width with around 58mm string spacing at the bridge (2 5/16").

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

Todd,

As I said, my measurement are from one of my lutes, an 8-course Heiber style.

Centre to centre at the nut, within each pair, the gap goes from 2mm at the treble to 2.5mm at the bass. Counter-intuitively for the guitar builder, at the nut the gap between courses is greater on the treble side than on the bass side, treble courses are 6mm apart whereas bass courses are only 4mm apart. Total width at the nut for the 8 courses (15 strings) is 53.5mm

The strings spread out towards the saddle, not only do the gaps increase between the courses but also within the pair. So that by the time they reach the saddle the treble pairs have a gap of 4.5mm and the bass pairs 5.5mm. The gap between courses also increases to 8.5mm treble and 9mm Bass for a total saddle string width of 95.5mm.

It all makes sense when you play one!

Colin

_________________
I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Thanks, Dave and Colin. Good, mind-expanding input from both of you.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Dave, one more thing. With the scale lengths, string gauges, and tunings you use, how would you describe the resulting feel, in terms of string tension, on the double course instruments you've designed? Is it much like a guitar, stiff like a mandolin, or even real loosey-goosey like a banjo? (One purpose of my question is to consider whether I might want to give a bit more room between the two strings within a pair if my strings are likely to be significantly more floppy than yours; or do you think the 2-2.5mm spacing you've suggested is plenty generous for even a relatively low tension instrument?) Any further thoughts on string tension in terms of the feel, playability, and sound of these instruments? Have you been aiming for a more mandoey sound or a more guitarey sound, or what, and what has been the result?

Then, if you want to go into it, I'd also welcome any thoughts on bracing the top with regard to these issues.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Todd,
Actually, the tension with the gage strings I chose turned out faily loose. Enough so you can easilly bend notes if you want to. I wanted to keep them on the loose side because of the doubled strings and I wanted it to be fun to play. The Mandoleles do sound guitar like, kind of like a mini 12 string. They are flat tops with fixed bridges and X brace with 2 finger braces and one redused tone bar brace. The less bracing I use seems to promote a bassier responce.
I hope this helps.

Wade

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Wade
Nashua, NH
http://www.wadefx.com

Hi Todd,

I couldn't possibly comment on how a banjo feels .

I make guitar bouzoukis with a few different scale lengths. The "Big Boy" I made for me has a scale length of 25.75", a 16" width lower bout and maximum body depth of 4 7/8". This is tuned GDAD and I think of it as a guitar that has lost the 3rd and 6th strings. I use string gauges of 0.012", 0.016", 0.032" and 0.042". It feels to me like a guitar being played in a dropped tuning such as DADGAD:

I also make a short scale travel guitar-bouzouki, "Celtic Tigger", that has 23.8" scale length, 11 1/4" lower bout width and 3 1/4" max body depth. This is also tuned GDAD and has the same string gauges on it. This feels a little looser, but works well and still feels like a guitar to play. this is close to how your proposed instrument will feel I suspect:


I would keep the unison pairs at around 2mm apart for the unwound and 2.5mm for the wound as if you make them wider they are hard to fret cleanly and hit with the pick. If you are worried about floppy strings "colliding" this is not an issue with the travel 'zouk.

The reason I make guitar shaped bouzoukis (apart from the fact that I like the sound which is more mellow and guitar like but with the same "cut" you get with bouzoukis - dig out somy Andy Irvine or James Fagan recordings if you can) is that I use my guitar bracing patterns and largely build them as I would a guitar. I tend to put 3 finger braces per side on the big one as a concession to the higher strng tension, but this is not that great, around 186lb in total. The bracing on the smaller travel 'zouk is simplified a little. I build them (as I do my guitars) with significant top arches - the main braces are radiused to around 15'. This gives some of the arch-top effects without carving. here's a pic of the top bracing on the big and little one:



By the way, the double courses offer perfect support for a slide and these instruments sound really cool - and I mean COOL - played this way. Martin Simpson put me onto to this one.

Hope this helps. Feel free to e-mail me if you want more info.

Dave White38804.5824768519

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

Dave, thanks so much. That was very helpful. This instrument I'm designing is sort of an oblong teardrop or egg shape. Nevertheless, I'm planning a fairly guitar-like X brace. I am planning an elevated fretboard, though, so the whole soundboard will be active. I'm also planning a 12' or 15' dome on both the top and the back.

Wade, this is really fascinating me. Once again, I have played regular old six string guitars almost exclusively (not counting banjos, plus a little mandolin and bass guitar), so my experience with widely ranging string scales, tensions, and tunings on various mandolin family instruments and the like is very limited. But this is a mind-bender for me: you've got a 20" scale instrument, roughly the length of a regular guitar capoed at the fourth fret; you've got strings on there that are just about the same as a typical medium gauge set of guitar strings; you've got it tuned up _four whole steps_ from the notes of a regular guitar at the fourth fret; and it feels loose! ...Unless I've misunderstood you, and it's actually tuned an octave lower than what I thought you meant, i.e. to the same notes as the top four strings of a guitar played open.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

[QUOTE=Todd Rose]   But this is a mind-bender for me: you've got a 20" scale instrument, roughly the length of a regular guitar capoed at the fourth fret; you've got strings on there that are just about the same as a typical medium gauge set of guitar strings; you've got it tuned up _four whole steps_ from the notes of a regular guitar at the fourth fret; and it feels loose! ...Unless I've misunderstood you, and it's actually tuned an octave lower than what I thought you meant, i.e. to the same notes as the top four strings of a guitar played open. [/QUOTE]

Todd,

As Wade describes it, the sting tensions will be 21.3lb, 20.2lb, 16.2lb and 14.4lb (D G B E) - pretty loose!!. Keep the same strings and tuning and shorten the scale length and tension goes down.

_________________
Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

[QUOTE=Dave White]   

Keep the same strings and tuning and shorten the scale length and tension goes down.[/QUOTE]

Right, understood. In his original post on it, Wade said he tunes it _UP_ to DGBE, so I assumed he meant tuning it an octave higher than the open strings of a regular guitar (which would be, as I said above, 4 whole steps higher than the notes of a normal guitar capoed at the 4th fret - 20" - and would therefore have much higher tension than a normal guitar). Also because he calls it a mandolele, I figured he was talking about a high-pitched instrument.

Todd Rose38805.398275463

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Just to follow up for any lurkers on this thread who may be interested - I PM'd wade and he told me that his 20" scale mandoleles are, indeed, tuned the same as a guitar, not an octave higher. My mind is unbent.

So, Wade, what's your spacing between two strings within a pair?

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

My spacing between each double string is about .080" or 2.03mm and remains close to that from nut to bridge. The space between each double pair however is .290", 7.40mm at the nut and .400", 10.18mm at the bridge.
This may seem wide. I made it up because it is comfortable for me. and yes, the strings are a bit loose. I like them on the lighter side as I play bending notes and such.
Also, the scale is 20.16". As if you took a 25.4" template and started at the 4th fret as your "0".
Good luck Todd and I hope to see pics of this creation!

Wade

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Wade
Nashua, NH
http://www.wadefx.com

[QUOTE=Wade S.] My spacing between each double string is about .080" or 2.03mm and remains close to that from nut to bridge. The space between each double pair however is .290", 7.40mm at the nut and .400", 10.18mm at the bridge.
[/QUOTE]

Sorry to keep pestering you for details, Wade, but are you measuring from string center to string center, or the actual space between the strings?

Thanks!

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

No problem Todd,
I like to messure between the strings and not on center so there is less confusion about gages etc. Having the same distance between pairs of the thicker strings (side to side, edge to edge) as the thin strings, makes the thicker strings slightly farther apart (center to center) but this makes sence to me as the thicker strings need more room to vibrate without slamming into each other. I don't think my fingers feel the difference anyway.
Keep in mind, I do little mesuring and tend to "eye ball" when setting up my instruments so the mesurments I posted here are aproximate.
I hope this helps.
Have Fun!

Wade

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Wade
Nashua, NH
http://www.wadefx.com

Thanks, Wade.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/