Thanks. At this point I'm considering trying the La Bella CB40 and CB60 string sets.
Anyone tried the CB60, 4 lowest strings, on a short scale ABG? Slightly smaller gauge than the 4-string CB40 set.
If anyone can explain how the intonation is dependent on the various variables involved, I'd love to learn more. I did a calculation shown in a
different thread that seems to indicate that the 0.080 D'Addario steel core will have a similar tension to the 0.090 Nylon core on my ABG when tuned down to E. If the intonation issues are related to tension, then this may not be a problem (using the stiffer "A" string as an "E" string on short scale). Or is the intonation problem related to the way the string bends when pressed down between frets? I'd appreciate any input on this.
My calculations linked above also surprisingly show that the unit weight as a function of diameter is similar between the nylon and steel core strings (for example, compare the nylon core 0.045 with the steel core 0.050 - nearly identical). I guess the majority of the weight is in the wound string, not the core.
I'm sure some physicist will come along and correct me when I go wrong, so here goes:
The simplest model for calculating pitch, works with unit weight, scale length, and tension while stretching a string between two endpoints. But that's based on the assumption that you have an ideal model.
Perfection is represented by the string having infinite flexibility, and the endpoints having infinite mass. Strings also perform the best when they are at the highest tension they can withstand without breaking.
The longer, skinnier bass strings are a big part of why fanned-fret basses like my 37" to 34" Dingwall have such good clarity and intonation on the low end.
That's where everything goes to heck with a short-scale, acoustic instrument. The endpoints of the instrument have nowhere near infinite mass, which is why they shake around so much and reduce the sustain. Plus, the shorter scale reinforces the inherent shortcomings of a real-world steel string.
Take a long-scale, hex core steel string:
- When you hold it right at the two ends, it seems pretty flexible, and "stringy".
- Yet when you hold it an inch from the end, it turns out to be surprisingly stiff.
- The shorter it gets, the more it behaves like a rod or a bar.
If you think about it, the evidence is all around us:
- The bridge saddle is angled more on a steel-strung guitar, than a classical.
- Nylon-core strings are floppier, and simply don't require as much compensation.
- This is also why string changes sometimes require sending Uke basses back to the factory to have the bridge relocated.
To repeat, the issue here is stiffness, not unit weight.
That's why the lower strings need more compensation in a steel core set, and why the bridge is always angled away from the nut on the bass side. The fatter the wire core gets on the lower strings, the less flexible they are when measured over short distances.
This is less of an issue on a nylon-strung instrument- although the weight goes up just like the bass strings on a steel-strung instrument, the wire in a bronze-wound nylon string is wrapped in a spiral, which allows it to be more floppy than a short, straight length of the same metal.
