[QUOTE=bob_connor]
This is the style of playing you'll hear from Donal Lunny, Donough Hennessy and Steve Cooney.
My friend, Ade, tells me that most of these guys are using guitars with slotted headstocks, and whilst I can't confirm it, this would lead me to think that they are 12 fretters.[/QUOTE]
Bob,
Donal is mostly a bouzouki man, Donough played a Lowden S guitar (cedar/EIR I think) when he was with Lunasa and I don't know about Steve Cooney but most if not all I've seen use 14 frets clear of the body.
Gavin Rawlston plays a Gibson and Jim Murray uses a nylon string (check out his playing with the Sharron Shannon band) so I don't think there is a definitive DADGAD guitar as such.
[QUOTE]Because of the keys that Irish traditional tunes are played in there is always a capo on second fret or above and nothing is used above twelth fret.[/QUOTE]
Warning - enetering pet-hate zone of mine

Well he's obviously never seen Ed Boyd of Flook play. Check out these performances at the Kennedy Centre
Flook
Capo's make for a very "styalised" accompaniment using 3 or 4 chord shapes. DADGAD is such an accommodating tuning to play anywhere on the neck using 2 or 3 left hand fingerings in ANY key with glorious open strings ringing out. EBEABE would not be a good tuning choice imho as a huge amout of Irish/Scottish stuff is in D G and A and your friend would miss out on the deep ringing D chords.
[QUOTE]He wants an OM/000 shape with enhanced bottom end.
My thinking at the moment is a deep body OM/000 with a 12 or 14 fret, 25.34 scale neck with an ADI/Lutz top and custom string gauges to compensate for the de-tuning.
Parabolic or scalloped braces I'm not sure of yet but I'm tending toward scalloped for the bottom end.
Back out of mahogany or EIR.
[/QUOTE]
I recently built a Lutz/Cuban mahogany guitar for an upcoming young guitarist in the Irish music scene Joe Bardwell:
This has parabolic bracing and was between an OM and SJ in size. Scale length is 25.75" and he uses lights (0.012"-0.053"). His original spec was for strong bottom end, but when we talked it through he needed projection, tone and string balance. It's not quite like bluegrass - if you want the percussive bass thud to drive the rhythm then you can alwas put on a 0.065" bottom string like John Doyle!!
This guitar is working out really well and Joe is playing it in the Manchester sessions scene. He sent me an e-mail recently and said that Mike McGoldrick has played it and liked it. Great advertising copy for my guitars - "As played by the greatest flute/whistle player"
If your friend really wants to cut through in a session then build him a guitar-bouzouki. In a lot of ways I think it fits in a lot better.
Dave White39102.3602314815
_________________
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