What's the deal with double dots on the 7th fret

[Chistopher]

I don't usually venture over to the acoustic side of the house, but over New Years I got the chance to play a replica of Johnny Cash's famous D-35. The first thing I noticed was that it had double dots. Apparently a good bit of Martins have that style of inlays.
I assumed that the reason is because when people play acoustic they need the fret markers for a different reason. Electric players use them to know where they are further up the neck and the octave has two inlays because it's special, but I assume acoustic players use them as warnings of sorts. The 5th fret dot means "ease up buddy, you're getting kind of crazy" and the double on the 7th means "you really shouldn't be up here". But what's the real reason?
Please note the above comments come from a guy who built a five fret acoustic with the chord diagrams for E,A,D,G, and C as inlays for his brother in-law.

[Mincer]

Re: What's the deal with double dots on the 7th fret

I guess, like many other things...tradition? Martin did it, and many other companies copied them. So we now have a lot of acoustics in the wild like that. Another thought is sort of what you said..the acoustics' 7th fret is sort of like the electrics' 12th fret- it is easy to figure out where you are.

[Chistopher]

Re: What's the deal with double dots on the 7th fret

I understand how it could be tradition, but I wonder how it started. Is it really that hard to remember the second dot is the 7th fret? It could also mark the perfect 5th of an open string, but I don't really see the point in marking it any different than the others.

[Mincer]

Re: What's the deal with double dots on the 7th fret

I have no idea who started it, but many early guitars didn't have a 3rd position dot. So it would make sense to have 1 dot, 2 dots, 1 dot, 2 dots from a visual/location standpoint.

[PFDarkside]

Re: What's the deal with double dots on the 7th fret

Probably decorative, then tradition.

[Aceman]

Re: What's the deal with double dots on the 7th fret

Just cuz.

[Gtrjunior]

Re: What's the deal with double dots on the 7th fret

I always just assumed that they are fret markers just as electric players use them.

[Silver]

Re: What's the deal with double dots on the 7th fret

Maybe something to do with using a capo?

[AlexR]

Re: What's the deal with double dots on the 7th fret

Well, 7th and 12th frets are 5th and octave notes from open string. The octave is the first to get the extra visual embellishment in most instances.....so the 7th is only logical to be the second.

[Swampy]

Re: What's the deal with double dots on the 7th fret

Is it really that hard to remember the second dot is the 7th fret?

Could be, since the second dot is the 5th fret.

[Chistopher]

Re: What's the deal with double dots on the 7th fret

Could be, since the second dot is the 5th fret.

Not on Martins. They don't have a 3rd fret dot.

[Swampy]

Re: What's the deal with double dots on the 7th fret

Not on Martins. They don't have a 3rd fret dot.

Ha! Shows what I know about them there acoustical's.

[Chistopher]

Re: What's the deal with double dots on the 7th fret

That brings another question, what's the deal with guitars that have a 1st fret dot? It looks dumb and helps no one.

[PierceOkken]

Re: What's the deal with double dots on the 7th fret

The reason for the double dot is because that is where the string length is cut in half. The 12th fret on the electric is the halfway point between the bridge and nut. The significance of the halfway point is it is where the vibration value of the string is doubled and the resulting pitch is an octave above the open string. Thus the "Double dot" for octave. I am not really sure why your acoustics have it on the 7th fret becuase all acoustics I have seen and owned have had it on the 12th fret like an electric.

[Chistopher]

Re: What's the deal with double dots on the 7th fret

I am not really sure why your acoustics have it on the 7th fret becuase all acoustics I have seen and owned have had it on the 12th fret like an electric.

The fancier Martins have them.