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  #76  
Old 01-10-2019, 10:44 AM
EvanB EvanB is offline
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As usual, you've given me something to ponder. I'm not sure about the exact scale of the X7 electric but I'll be doing some measurements and see what I have--whatever it is, it plays well and sounds good.
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  #77  
Old 01-10-2019, 08:01 PM
ceciltguitar ceciltguitar is offline
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There are a lot of 630 mm scale length classical guitars that have good tone and good projection. Plenty of players on the Delcamp forum have spoken highly of their 630 mm scale length classical guitars. I have also seen several players mention having 3/4 or 7/8 size guitars, including 3/4 to 7/8 scale length, that were happy with their instruments.

I owned a student grade Kenny Hill 630 mm classical guitar for awhile just a few years ago. It was a fine guitar, and I liked the shorter scale length. I still sometimes entertain thoughts of acquiring a concert level 630 mm nylon string guitar.

Of course, one can always just use a capo bar. I do that a lot too, on all of my 650 mm and 640 mm scale length guitars, especially the ones that have 24 reachable frets, including my 2018 640 mm scale length cocobolo Emerald X10 nylon string beauty.
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  #78  
Old 01-10-2019, 09:10 PM
Tom2 Tom2 is offline
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I can see a smaller guitar having a shorter scale, since less string tension is needed to drive the reduced mass of a smaller soundboard. Maybe that's why Alistair was open to a shorter scale on an X7, but not on an X10.

You have experience with 650mm, 640mm, and 630mm nylon. If you were designing a custom guitar for yourself, with the intention of it being your main guitar, which scale length would you choose?
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  #79  
Old 01-11-2019, 09:14 PM
ceciltguitar ceciltguitar is offline
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Quote:
Originally Posted by Tom2 View Post
You have experience with 650mm, 640mm, and 630mm nylon. If you were designing a custom guitar for yourself, with the intention of it being your main guitar, which scale length would you choose?
That's a good question.

In regards to Emerald CF guitars, Alistair did not want to go below 650 mm scale length. I asked for 630. We settled on 640. To me, the custom X10 that he built with 640 mm scale length has a magical sparkling sound. I am VERY happy with this guitar! However, I still also love to play my wooden guitars. And I still gig exclusively with a nylon string Parker Fly, primarily due to the nature of the gigs that my wife and I (all too rarely) do.

CF has different response properties than wood. I believe that the reason that Alistair wants longer scale lengths for CF guitars is that the response properties of CF require a higher string tension than wooden guitar tops require in order to produce good tone at a good volume. I suspect that he is basing his opinion on his experience building and experimenting with building guitars. So he is probably right.

Yet he also builds nylon string Amicus models, which have a much shorter scale length. Maybe the tradeoff is high string tension with higher pitched strings?
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  #80  
Old 01-12-2019, 10:28 AM
EvanB EvanB is offline
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Could the thinness of the X7 contribute to its exceptional projection? Alistair and I were both amazed at the projection of the thin bodied 7.

I'm not sure that CF requires greater string tension. I've been using normal tension strings on my RS Parlor and the guitar projects quite nicely. Perhaps the very hardness of CF leads to a resonator-type effect?

That said, I still have yet to play a nylon strung CF instrument that resonates to the level of a good classical guitar.

It seems to me that there is still a lot of mystery in the development of carbon fiber instruments.
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  #81  
Old 01-12-2019, 12:51 PM
ceciltguitar ceciltguitar is offline
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Interesting observation, Evan. Both of my X10 nylon string guitars are notably quieter than my traditional classical guitars.

Is your slim body X7 louder than your new (and deeper bodied?) X10?
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  #82  
Old 01-12-2019, 01:24 PM
EvanB EvanB is offline
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Cecil;

Its very close. The new 10 has more electronic innards and I suspect they lead to greater electric power but diminished acoustic voice. I'm guessing here. I have no explanation for the acoustic projection of the 7 electric. It's a mystery.

I have used my brother-in-laws Ramirez as the comparison point with my Blackbird, Emerald, and RS nylon string instruments. The CFs all do well tonally, but do not project like the woody. CF haven't been shaped like wooden tops and that may be a limitation. Or, it may be that CF tops need to be thinner with tone posts or bracing for support??
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  #83  
Old 01-12-2019, 07:24 PM
Tom2 Tom2 is offline
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CF is much more rigid than wood, so its natural frequency will be higher. With the lower tension and diminished overtone energy of nylon, this requires a new way of thinking about soundboards.

The typical bracing patterns of wood soundboards protects the wood from saddle torque. With nylon, this isn't so much of an issue, if at all. A very slight archtop design is all that's necessary.

Instead, the lower bout of a nylon/CF soundboard can be designed similar to a drum head, with bracing providing the function of a drum rim, completely encircling the lower bout.

A perfectly elliptical lower bout would be a nice drum head, and an additional layer of CF around the elliptical edge would create a boundary condition that reflects string energy back into the lower bout, increasing projection and sustain. This kind of bracing would create a more resonant soundboard than having no bracing at all.

Energy transmission and reflection at boundary conditions is probably not a common design consideration for guitar makers, but the strength of CF offers the opportunity to think differently.
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  #84  
Old 01-13-2019, 08:23 AM
mountainmaster mountainmaster is offline
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Interesting points Tom2. Just makes me wonder why bracing is used for the X20 nylon but not for other nylon models.
Quote:
Originally Posted by the Emerald webpage for the X20 Nylon Artisan:
It has a really big voice, and with the modified lattice braced top we developed (a key, unique feature on the X20 Nylon) it has a huge bottom end, but still has good treble notes.
Regarding tension, to me it was a big surprise how much the tone and resonance of my X7 nylon improved when I put on lower tension strings. Is it possible that too much tension beyond a certain point somehow chokes the sound?
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  #85  
Old 01-13-2019, 12:56 PM
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Quote:
Originally Posted by mountainmaster View Post
Regarding tension, to me it was a big surprise how much the tone and resonance of my X7 nylon improved when I put on lower tension strings. Is it possible that too much tension beyond a certain point somehow chokes the sound?
I think that's perfectly possible. While I've never experienced it myself, I've seen the phenomenon described many times for 'conventional' guitars.
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  #86  
Old 01-14-2019, 10:24 AM
EvanB EvanB is offline
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I ran across this with my RS parlor. I tried normal tension strings and it was if the guitar opened up--better projection and sweeter tone. I'm not sure how this can be explained, but I have a theory.

I've noticed that as I move to harder tensioned strings the sound becomes increasingly steel-like and looses the warmth of nylon--the harder I strum or pick the more metallic the sound. I don't think that normal tension strings really project better, but I think I can play the normal tension strings harder and still retain warmth.

Not sure if all that makes sense. What is clear is that new materials, builds, strings, and so forth are leading to a different kind of guitar, one still in process.
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  #87  
Old 05-15-2019, 10:29 AM
EvanB EvanB is offline
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The ultra-thin bodied, nylon string, woody is on. Well, the veneer has been picked and the billing is on its way. A squeaky wheel does get attention.
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  #88  
Old 05-15-2019, 01:48 PM
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kramster kramster is offline
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Quote:
Originally Posted by EvanB View Post
The ultra-thin bodied, nylon string, woody is on. Well, the veneer has been picked and the billing is on its way. A squeaky wheel does get attention.
Go squeaky Unc go!!
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  #89  
Old 05-15-2019, 03:33 PM
Mark L Mark L is offline
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Bravo for Emerald stepping up to the challenge.
I hope it works out well for everyone.
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  #90  
Old 05-15-2019, 03:54 PM
ceciltguitar ceciltguitar is offline
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Congratulations, Evan!

Another Barbera? Or what?
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