with my steel string guitars, i've grown to prefer what we call shortscale(usually just under 25" so around 24.9 or 24.75").

thru my research it appears longer lengths were preferred aways back(660 or more) and over the last few years 650mm is now somewhat standard.

what about 640mm? What does one give up with that versus 650mm?

i do like the shorter reach but understand the frets will be slightly closer overall. i assume maybe the shorter scale drives the top a little less, so maybe slightly less in volume?

i have not played a 640mm length but have played 650 and find it more comfortable than my Conde EF4 which measured out to be 664mm.

feel free to correct my thoughts and offer any info.

i need to decide this due to my build in a year.

thanks
daryl

Hi Daryl,

Welcome to the forum!

There is just a little difference, but the only thing I can think of as maybe a disadvance is that in the future you want to use a capo more than you do now.
Is it still confertable to play for instance a bulerias or Solea with the capo on fret 3 or 4?

I have some thoughts about scale lengths.

I have Ramirez classical and Contreras flamenco guitars with 664mm (26.14 Inch) scale lengths that I purchased in the 1960's and 70's when that long scale-length was popular. When starting to play again after many years during which I had played very little, the necks of those guitars seemed extremely long. It seemed difficult to reach my arm all the way to the first fret and it also seemed like my fingers were too short to span several frets near the far end of the neck. My 1970's vintage Ramirez flamenco guitar has a shorter neck and it seemed much easier to play. However, after a few years of playing again my perceptions have changed. My long-neck guitars don't seem any more difficult to play than my shorter-neck guitars.

I think there is a simple reason for that. Arm and especially finger reaches can be increased with practice. Ranges of joint motion decrease over time unless joints are frequently stretched. I will be 74 years of age in a few days. Unless someone my age has frequently stretched the rotation of their joints to maximum limits their ranges of joint motion will typically be much less than a younger person's. Even so, unless joints are diseased or have been mechanically damaged by accidents, those limitations are largely reversible with frequent practice. I now find it easy to reach long-stretch chord positions that seemed impossible a few years ago when I started playing again.

That improvement is associated with another thought about scale lengths. Flamenco is most often played with a cijilla which shortens the effective length of a guitar neck. Someone who has difficulty playing a long-neck guitar can simply shorten it with a cijilla. Other than a longer necked guitar being a little heavier, scale length isn't an issue if it is played with a cijilla. Even though most flamenco is commonly played with a cijilla, Zambra's are often given a deep bass sound by playing them with an open D tuning obtained by lowering the 6th-string one tone, so both the open 4th and 6th strings are D. My Contreras negra guitar sounds especially nice when tuned that way and played open without a cijilla. I usually use it to play Zambra's and frequently playing a 664mm scale-length guitar open over recent years has made it easy for me to now play long-neck guitars.

There is considerable advantage to having several guitars, because they are each best in different ways, because playing different guitars tends to make a player more versatile, and where they all sound different, changing from one to another adds variety to the music produced.

-Bob

My personal opinion is a 650 scale is perfect because I think it is the ultimate in getting the traditional sound. A longer scale as well as a shorter scale will effect volume, tone, etc. Maybe ever so slightly, but still has an effect which may or may not be a players first choice. For example the tension on a longer scale is less than a shorter scale. While the pitch is the same, the characteristic are different. For extremes compare a 630 to a 670. The 630 has less presence of tone and the 670 has lots of presence but in my opinion is somewhat mask in the trebles. To explain the term presence it means to me to expand the reproductive frequencies of the guitar beyond what the lowest and highest note used are. Making the body larger, deeper, etc will tend to favor bass and dampen trebles. Having had a deep bodied guitar at 655 scale, I can tell you the trebles were slightly masked or dulled by the size of the body. They were loud and had very nice tone, but not as nice a trebles or bass growl as I like. The bass was deep but more "boomy" in my opinion. Making the body to small the guitar becomes to "tinny" and shallow. Putting a longer or shorter scale on a body like Santos, Torres, Barbero, etc., will have a very minute effect on the presence, tone, and volume to the ear, but I find the big difference is in the feel of how the strings can be manipulated which may cause the player to not play to their capabilities. I think a 640 open would feel alright. but with cejilla at 2nd or higher would be a bit stiff or tight feeling to the fingers. Maybe ligatos would be not so pronounced, etc.

Because string tension is less you might find a longer scale easier to press down the strings, but the reaches are longer. All my guitars are now 650 as I like the idea of having them all the same. I play 80% of everything with cejilla at the 2nd fret. I like the feel and sound there and most of what I play (siguiriyas, soleares, alegrias, bulerias, tango, fandango, sevillanas) never goes higher than the 12th fret with cejilla on 2nd. Open I play Malaguena, Guijiras, Taranta, Tangranta (my own palo not real flamenco), etc., and do a lot of practice octaves and scales there. Occasionally a Tango or Farruca if I want to show the full range of the guitar.

I find 640 a bit short for using the cejilla. I think 650 scale would have the best resale as it is standard and used by both men and women and has the best over all traditional characteristics. It is a very personal choice. Many classical players with small hands are going to 640 and find it to be more comfortable.

SamC wrote:My personal opinion is a 650 scale is perfect because I think it is the ultimate in getting the traditional sound. A longer scale as well as a shorter scale will effect volume, tone, etc. Maybe ever so slightly, but still has an effect which may or may not be a players first choice. For example the tension on a longer scale is less than a shorter scale. ...

It is true that string lengths affect sound volume, because more mechanical energy is stored in longer strings if they are deflected equal amounts. However, longer strings oscillate at lower frequencies if string tension isn't changed. (the musical pitch is lower if a string with a given tension is stopped at the first fret compared to the second, etc.) Therefore, longer strings must have higher, rather than lower tensions, to have equal musical pitches.

Exhaustive human perception experiments (in a scientific field known as psychoacoustics) have demonstrated that at normal listening levels is it necessary to increase sound volume (actual loudness) approximately ten times for an average listener to perceive that sound is twice as loud. Increasing string length ten-percent increases stored energy ten-percent for a given amount of string deflection when strings are picked. Most of that energy is converted to sound when deflection is released (the rest is converted to heat). A string that is ten-percent longer will produce ten-percent more actual sound volume, but because ten-times more actual volume needed to sound twice as loud to a human, a mere ten-percent increase is almost imperceptible.

There is a 40 mm length difference over the extreme guitar scale length range from 630 to 670 mm. 100(40/630) = 6.35%, so the actual sound volume produced by a guitar with a 670 mm scale length would be 6.35% greater than actual sound volume produced by a guitar with a 630 mm scale length. However, 6.35% is substantially less than 10%, so it reasonable to conclude that the volume difference perceived by an average listener would be near zero.

-Bob

I own five guitars which are 650 (3 CG, 2 FG), and four which are 640 (2 CG, 2 FG), and one CG that is 664. Here are some thoughts presented in a fairly random order:

I have come to realize that I like the "idea" of 640 more than the reality of it. I find my fingers get too scrunched up in the high frets on a 640. That being said, there are some real values to the 640 size.

People will say "There's only 5 mm difference on the playing side." Mathematically, that's correct. Moreover, there's only 2.5mm difference from 0-6 on a 650 v. a 540. I've measured the distance from F to A, 1st fret 5th fret, on the two sizes, it comes to ~124mm on 640 v. ~126.25mm on a 650. That's an approximation, but close enough. So unless you can magically add that 2.25mm to your fingertips when playing in the lower frets, that can make a helluva difference, a difference between a clear sounding note and a muffled buzzy rattling one.

As Bob pointed out, the actual volume differential is negligible, and two of my 640s are certainly louder than a couple of my 650s are. This is based on the builder's skill. I have a 640 and 650 by Johnny Walker (his ad frequently pops up on the masthead of this site's main page) and they are nearly equal in volume & projection.

The guitars I find myself playing all the time are my 650s.

The guitars I can sell quickest are the 640s because a lot of people want one. I would bet I could sell my Johnny Walker 640 peghead Barbero replica pretty damn fast, if I wanted to. At this point, I don't want to, unless I got a great offer.

Changing between 650 and 640 is a hassle, and changes between the two sizes throw me off for a little while until I acclimate. Same thing in reverse, mainly on big shifts (e.g. Carcassi's etude #1).

I only keep that 664 Alvarez from sentiment, it was the guitar I learned on, and it has a resale value far less than the collective encompassed playing memories are worth.

Hope this somehow makes some sense.

thanks for the replies folks.

i definitely have some things to work out before my build begins.
i've never played a 640scale Flamenco so thats one big hole in my thought process. i know i'm comfortable with the 650length and thats a safe spec to highly consider.

anyone else with a present or past review of a 640mm scale use please reply

d