The most common neck shape of a bass neck is C. But are all C shapes the same?
If you have ever entertained the idea of replacing your neck and you absolutely have no idea which shape to choose from, the “safe” option is “Fender Modern C,” even if it’s not made by Fender. In literal terms, this particular shape is a slim oval. To get an idea of what this neck shape feels like, all you have to do is pick up any USA or Mexico-made Fender bass guitar and you’ll know what it is.
For those of you wanting a more vintage style thicker neck of the Fender-like variety, this is known either as a “Big C” or a “Large C.” While still a C shape, the neck is physically thicker and you will immediately feel the difference once you put your hand around it.
Understanding width
With certain different C shapes come different widths. The easiest way, at least with a 4-string, to get a feel for neck width is to compare a Fender Precision Bass to a Fender Jazz Bass.
Generally speaking, the Jazz bass is always skinnier at the nut compared to the Precision.
At the time of this writing, an American Standard Precision bass has a 1.625-inch (41.3mm) nut width. The Am Std Jazz has a significantly skinnier 1.5-inch (38.1mm) nut width.
Know that the width gradually increases as you go up the neck, but since the majority of bass players play mostly on the first 5 frets, it’s the width near the nut that matters most.
As a player, you will know fairly quickly whether you prefer the skinny nut Jazz or the wider Precision, so it is suggested you try both to see which works best for you.
Can you put a P-style neck on a J-style body and vice versa? Yes. On like-to-like model years for Fender basses for example, it’s usually true you can swap out a P neck for a J neck and it should bolt right up without a problem (but know you will most likely need to adjust the shim along with the truss rod.)
Understanding fretboard radius (for fretted basses)
The C refers to the shape of the rear of the neck. A fretboard radius refers to the curve of the fretboard and changes the playing characteristic of the instrument depending on the curve used. The higher the number, the flatter the board. The lower the number, the rounder the board.
The vintage-style fretboard radius is rounder. For a Fender style vintage neck, the radius would be 7.25-inch.
The modern-style fretboard radius is flatter, and can be anywhere from 9.5-inch and up.
Some players prefer super-flat fretboards, and it is not unheard of to have a 16-inch fretboard radius, even on a 4-string bass.
If you are unsure which fretboard radius to go with for a replacement neck, the safe range is 9.5-inch to 12-inch.
Neck shape by manufacturing year
Fender, for example, will periodically release a reissue instrument such as the American Vintage ’64 Jazz Bass model, which touts a “period correct neck shape.”
Certain years in which a particular bass was manufactured have a very specific neck shape to it, and the ’64 is one of them. While the shape is a C, it’s a specific-to-1964-shape C. And yes, that does mean it will feel different compared to a Fender Modern C.
The only way to really know how this neck feels is to play it, as this is something that really cannot be described in words, other than saying it’s slimmer (according to Fender.)
And on a final note, “old,” or rather “old design,” does not necessarily translate to “good.” What’s good is whatever feels correct in your hands, be it vintage or modern, fat-necked or skinny, wide or narrow.
What’s your favorite C?
Vintage? Modern? Something different? Post a comment or two with your C shape experiences.
I have and play J’s, P’s both vintage and modern nut width. They are mostly J’s but love them all.
This is one of those areas where similar terminology describes different things. You are taking the path that the shape of a letter describes the curve of the back of a neck. From that point of view, there are also V necks and D necks on classic Fender basses. BUT Fender’s letter C in the stamp on the heel of a neck meant 1and 3/4″ width at the nut, and a letter A meant 1 1/2″ width at the nut. In the 1970’s a lot of P basses went out with A necks but the P bass standard was the C neck. And the J bass standard was the A neck.
This article takes the path of the shape of a letter describes the shape of the back of a neck. By this standard, there are also D and V necks on classic Fenders. But Fender use the letters A and C to describe nut width, not neck shape, A meaning 1.5 inches and C meaning 1.75 inches.
1.625 is 15/8″ if the neck was 1.75 thick at the nut, then, yes, 1 3/4″
I play mostly upright. Now I know why the J-bass with the smaller radius finger board feels better. The proportions are more similar to the upright. Thanks
are large frets better for bass?
I prefer thicker Frets
I had a 1965 Fender Jazz that I bought in 1966. I used that bass in high school and college and used in a a touring night club group for 3 years in the early 70’s. We played 5-nights a week, 50-weeks a year for three years. I got to know that bass intimately and I loved it. Then in 1976 it was stolen and never recovered. I tried out every Fender Bass I could find looking for another Jazz Bass with that neck.
I finally found one in 1985 while working part time at an area music store. As soon as I pulled it off the wall and ran through some of the stuff I used to play I knew that was the one. I still have it and gig with it weekly.
The neck I have has been described as a 60’s shallow C-shape. It is slimmer than any other Jazz Bass I have played outside of my original 1965 Jazz. It also has a 7.25″ radius with rounded edges and white binding on the neck. Supposedly Fender only offered that binding on their 1966 and 1982 Jazz Basses. According to the parts numbers, mine was made in late 1982 (40th+ week). My ’65 had a maple neck with a rosewood fretboard. My current bass has an all-maple neck and fretboard.
I was actually interested to see Fender come out with their ’64 Vintage “period correct” bass because it looked like they finally put the neck I have on some other Jazz Basses. They talk about the “Slim C-shape” and then say they put the 9.5″ radius on it. There is absolutely NOTHING period correct about a 9.5″ radius neck on a ’64 Jazz Bass. It was a 7.25″ radius, just like my 65 was and like my 82 is. Makes me a little crazy. You shouldn’t advertise it as period correct when it’s not. Hope nothing ever happens to my bass because I’ll have to go to the custom shop to get one made to the correct specs.