Nylon crossover bridge position, 12 fret vs 14 fret

Tom 2;

Your analysis stuns me. I tend to engage in a certain amount of slop. Aristotle says we should not warp the rule, but occasional I put up with certain amount of warp. You are precise.

And so, I would like, if you have the time, to hear your take on a nylon string electric guitar. There is a thread for such and I am working toward one; a 12 fret, 1 7/8" nut, 24.9 scale. What do you think about that?

[Tom2]

Originally Posted by EvanB

Tom 2;

Your analysis stuns me. I tend to engage in a certain amount of slop. Aristotle says we should not warp the rule, but occasional I put up with certain amount of warp. You are precise.

And so, I would like, if you have the time, to hear your take on a nylon string electric guitar. There is a thread for such and I am working toward one; a 12 fret, 1 7/8" nut, 24.9 scale. What do you think about that?

Funny you should mention this.. I was just having lunch with Aristotle the other day at our favorite breatharian restaurant (We go for the atmosphere. Their aether is to die for.) and even he said I was a bit extreme.

I'll check out your other thread.

[Tom2]

Originally Posted by sirwhale

636mm scale is incredibly comfortable with the current Thomastik Infeld PJ116 strings on it, easy bends, easy barres, no loss in power - it projects well.

I've just had a quick search, and there's pretty much no factory 640 crossovers out there. Mine is probably the only one I can find shorter than 650, and it is made in Spain, so not sure how popular that will be overseas. The Carbon fibre world would be good to offer a 640 crossover, but I suppose most companies will have their default moulds at 650mm. So unless there is a sudden rise in popularity in crossovers, it'll all be for extra costs.

Emerald have emailed me saying that the price of the crossovers can be reduced significantly when removing things like the head stock, bridge and finishes. But it's still too much for me at the moment. As said, I would want a 640 scale, 12 fret, and these would be add-on features too. Maybe in the future when I stop spending so much money on experimenting with strings (I promise that I am now very happy with these "rope core" strings on my crossover, really).

In my opinion, the shortest scale length that does the job is the best scale length. For you, it's string bending. For me, it's low action. You have verified that 636mm is very comfortable. I have verified that 645mm allows the first string to be 2mm above the 12th fret. I would gladly go shorter if I can still get the 2mm string height.

While I can experimentally determine optimum string spacing and height by making custom nuts and saddles, it's impossible to experiment with scale length. I'm just guessing that a 5mm reduction from 645mm will not require raising action, while a 4mm increase from 636 will not interfere with bending. At the very least, I'm comfortable saying that 650mm is not necessary.

When this gets sorted out, the popularity of crossovers could rise dramatically, and if the dimensions are crystallized in a production model, the price could also go down dramatically.

Tom 2;

Much better to drink with Aristotle than Socrates.

[Tom2]

Originally Posted by EvanB

Tom 2;

Much better to drink with Aristotle than Socrates.

Good call. That's precisely what "to die for" was referring to.

[JimCA]

Great thread Tom (lots of Toms and Jims on the forum).

I am currently awaiting an X7 nylon with 632mm scale, en route, somewhere between Ireland and my door.

In addition to scale, another tunable aspect is string tension. String tension for a given string at a given pitch is proportional to the square of scale. So how do I get the same tension on my 632mm X7 as on my two 650mm nylons? I have D’Addario EJ46 (Hard Tension) strings with 89.9 pound total tension on my 650s. To match that I need:

tension632 = 89.9 * (650 * 650) / (632 * 632) = 95.1 pound advertised D’Addario tension

D’Addario offers:
- EJ45FF: 94.6 pounds
- EJ46FF: 102.6 pounds
- EJ44C: 106.4 pounds

(And, there are other string makers to consider).

This doesn’t address tone, so that’s still an experiment among string options.

Then there is the amplitude of string vibration for a given scale, string tension and pluck force. This gets at Tom’s goal of 2-3mm action at 12th fret. I don’t know the answer to this - I welcome input from a physicist that does. I “guess” that shorter scale with same string tension and pluck force would have less amplitude than longer scale. But, somebody who knows, please enlighten us.

Jim

[sirwhale]

I agree that 640 seems to be the best trade off. On my 636 scale I have the action down at 2.5mm on the high E and I'm quite happy with that. I'm quite heavy handed. Many people on the Delcamp forum seem to be going for 640 scales. I'd love a crossover with this scale and a small cut away.

But 650 scales are dominant now and that's why I'm trying them out. I'd be happy with my guitar, but has laminate back and sides and no bass below the low A. Sometimes I like a guitar that doesn't have a dominating bass, but sometimes I want to get that deep low E, or Drop D growl.

Tom have you tried the Thomastik Infeld Classic S KR116 strings?


Jim, if you want to know your tensions, then companies are not so reliable, Savarez for example publishes some very suspect tensions. If comparing across companies, and I want to know about different tensions on different scale lengths, then I use Arto's calculator:

https://www.cs.helsinki.fi/u/wikla/m.../wwwscalc.html

Scroll down to the see the suggested "densities" to input.

In terms of the amplitude of the string vibration, my understanding is that if the string is at the same tension and is the same material, the amplitude should be the same. But, I'm guessing that if it is a shorter scale, and you increase the gauge of the string (same material), then the amplitude may be less due to internal friction. But then, as the string is thicker, it can touch the frets slightly easier than a thinner string. So, swings and roundabouts, maybe.

[Tom2]

Right now I'm using EJ44 xht strings to achieve 2mm, so there aren't many higher tension options to accommodate a shorter scale. Maybe carbons.

For this thread, I'm more interested in how bridge location affects tone. The actual number of frets to the body is irrelevant, since it can be changed by modifying the upper bout, but it is the most common identifier of bridge location.

On your X20's and X7, where is the bridge, and what is your opinion on tone?

[JimCA]

sir:

You're farther along on your string search than me. I've been happy with my EJ46s on my 650 scale guitars -- although not so happy with 650 scale. Still haven't received my X7 nylon 632. I see that you have tried both the Thomastik and the carbon strings. How would you compare them?

tom2:

Carbons will definitely crank up string tension and reduce string width somewhat. Looking forward myself to see how they affect tone. Still haven't received X7 nylon, so I'll comment later on bridge spacing and tone.

Jim

[sirwhale]

The Thomastik Infeld Classic S KR116 have very thin trebles and make the fretboard feel like it has more space. I'm guessing you can achieve low action with them because of this. They sound like half way between nylon and steel. (I have one video of them Jim, more to come)

Carbons are also thinner than nylons, and they also have higher tension, so this will definitely help you keep your action lower (they sound better than nylon, in my opinion).

Tom for me, there just in now question about it, a bridge in the middle will always sound better. But, in carbon fibre, the moulds are all different to wood, so maybe a 14 fretter is made to have the bridge in the middle of the sound board. So in the CF, 12 frets or 14 frets to the body might not be the best indicator.

Assuming the bridge is in the centre, I would prefer 12 frets because of the ergonomics of not having to reach so far. If there is a cut away, there's no problems.

[CFW]

The bridge location changes on the x20 from a 12 fret to a 14 fret model. I also 'lost' a couple frets, as I only have 20, instead of the standard 24.

My feelings regarding a 14 fret to the body with a cutaway were similar to yours. I would rather take the benefits of the bridge being lower in the bout, the shorter reach of the 12 fret, but still getting access via the cutaway.

[Tom2]

Originally Posted by JimCA

I am currently awaiting an X7 nylon with 632mm scale, en route, somewhere between Ireland and my door

Was this recently ordered or recently completed? Evan is designing a 632mm X7 also, and any real world experience with custom X7 Nylons helps everyone.

[JimCA]

Originally Posted by Tom2

Was this recently ordered or recently completed? Evan is designing a 632mm X7 also, and any real world experience with custom X7 Nylons helps everyone.

Received it a few hours ago. NGD post coming soon when I recover from excitement of playing it after 5 month wait. It's a 13 fretter!!

Jim

[Strumalot]

Rainsong has done a great job (in my estimation) of producing a crossover 12 fret nylon string guitar, the nylon string Parlor. I don't think they have made a 14 fret version, probably for exactly the reasons you mention.

Evan, RainSong did make an NP14 (maybe only one) and I suspect Ted in LA knows more about that instrument...

https://www.youtube.com/watch?v=VhxHRGfTEvg

Anyway, thanks everyone of the interesting thread... I always enjoy learning about "guitar nerd" stuff!

From my nylon perspective ~ I don't know if I am a typical crossover buyer or a market of one ~ but my priorities would be playablility. For me, that's an electiric-like neck and upper fret access. I am still primarily a steel string player. I do like to cross over to the nylon side at times, but am not a classical purist when it comes to the sound.

So my X10N, which joins around fret 15 and has a generous cutaway, beats my RainSong NP12 which arguably sounds better but has reduced upper fret access.

I would be curious... do I represent a typical crossover customer or am I a market of one?

Strumalot;

Ted had mentioned a 14 fret nylon string guitar, but I had been unable to find a production model--thank you for bringing the custom model to the forum. I am pretty happy with the 12 fret.

I do not think you are a market of one. A true hybrid is going to combine the best features of a classical guitar with the contemporary developments such as cut-a-ways, electronics and so forth. One of the reasons I have liked the X10-OSN is that it does have the high fret reach and yet embraces many of the traditional values associated with classical guitars.

I have been reconsidering just how high I want to reach since as I get to those high places I start losing finger space and accuracy. I think a 12 fret with the right cut-a-way and design will get me where I'd like to be.