Over the years, the shape of the classical guitar body has increased in size. There have also been other evolutionary changes
changes in soundboard bracing
changes in string tension
and so it is not a simple matter to attribute the sound qualities of the instrument simply to one factor alone.
However it can be said in general that the larger the body the greater the volume of the instrument but that beyond a certain volume the sound acquires a “boomy” quality – a lack of clarity and separation of the tones.
If you compare the modern flamenco and modern classical guitars you see that the flamenco instrument, while its length and width (of the figure of 8 shape) are very similar, its depth from front to back is less. The tonal difference between the two is largely a matter of more attack and slightly less sustain on the flamenca than on the classical.
(Attack – the time taken between plucking a string and the note achieving its maximum volume
Sustain – the duration of the note sounding after it has been plucked).
You also find that a number of electro-classical guitars have a shallower body. This is typically done so that feedback is reduced.
A question often asked is whether a cutaway in a nylon string guitar affects the sound. Its physical effect is to reduce the volume of air in the body and so given the above discussion it is likely that it reduces overall volume and sustain and increases attack. From experience I think these effects are there but not very pronounced and masked when comparing one instrument to the next by the natural variations in the acoustic properties of the different pieces of wood making up the soundboards.
This article was written in 2016 and needs updating.
Many people ask about changing the string spacing on these guitars, particularly on NTX models.
To begin, here are the facts:
Neck width at Nut
Neck width 12th fret
String spacing at Nut
String spacing at 12th fret
String spacing at Saddle/bridge
Measurements in mm All measurements ours on new, standard stock instruments. All measurements +/- 0.5mm String spacing from centre of e1 string to centre of E6 string NTX includes NTX700, NTX900, NTX1200 NCX includes NCX700, NCX900, NCX1200
On both guitars the strings are closer together than is typical on nylon strings, and particularly so on the NTX versions.
A customer with and NTX who was finding the string spacing a bit “tight” asked :
“Can I get away with just replacing the nut?”.
“If you are finding the string spacing “tight” for the left hand then you need to begin by fitting a new nut with slots cut further apart than the standard nut. Even after fitting the new nut you may still find either the string spacing is “tight” for the left hand further up the fingerboard or “tight” for the picking right hand. If either or both of these is the case then you need to redrill the string tie-holes in the bridge further apart. The width of the NTX bridge is the same as that on the NCX version of the guitar and so there is considerable scope for increasing the spacing here. (However you would need to be careful not to space so widely that the strings were in danger of slipping off the side of the fingerboard over the upper frets!)
Cutting new nut slots and drilling new bridge string tie holes both require a bit of maths to do properly as well as careful and accurate cutting/drilling. If you mess up a nut it is simple to start again with another but this is not the case when drilling the bridge so take advice if you are not experienced in this. “
The Yamaha NTX series are nylon stringed guitars designed to feel familiar to the steel string player.
In addition to the body shape, the critical features are
14th fret neck/body join
Curved (radiused) fingerboard
48mm nut width
Now a 48mm nut is about as wide as you go on steel stringed guitars but as narrow as you go on nylon stringed.
However, it can be argued that the spacing of the strings is as important as the width of the nut itself. And here some people have expressed a criticism: the string spacing (measured at the nut) is just 37mms leaving nearly 6mms between the outside of the strings and the edge of the fingerboard. This is a lot, not just by steel string standards but also by nylon stringed classical guitar standards.
So when asked we have replaced the standard nut with one with 40mm string spacing. While the absolute difference is not great, the change decreases the spacing between the strings and the edge of the fingerboard by about 25% which feels quite significant when playing. While we are at it, we use a bone nut in the expectation that this has better tonal qualities than the plastic nut fitted as standard.
This modification can be done on the following models –
NTX700 (Natural and Black)
Measurements taken by us on the NTX1200R we first modified in this way were as follows –
Original string spacing
Original space between string and edge of fingerboard
(Please note that we only offer new saddles and nuts for guitars we sell ourselves and do not offer this as a general service for guitars bought elsewhere. Nuts are made and fitted for us by specialist luthiers and are more expensive that the saddles we make up and fit ourselves.)