Flatwound strings with the least tension in *relative* numbers

[ixlramp]

That raises the question as to how you could objectively compare something like stiffness/pliability. So many things come into play with this, as neck relief, string height, etc.. will all add/remove stiffness.

I agree. The 'stiffness'/'pliability' you mention is actually 'perceived stiffness/flexibility', and is somewhat subjective and also dependent on the bass guitar the strings are on.
So the only thing to do is to work with something scientific and objective (as tension is), which would be a scientificly recognised stiffness property. This would be the string structure resistance to bending while not on the bass guitar.

I have the - perhaps erroneous - impression that to nail the authority required for the relatively few notes of a reggae bassline strings must be of adequate gauge, namely not thinner than 45105.

That is erroneous =) I am guessing this is the reason behind your desire for '45-105 with low tension'.
It is also somewhat unreasonable to insist on certain gauges and then want a wide choice of tension. Tension correlates fairly closely to gauge because string construction has many constraints so cannot vary much (assuming you want metal flatwounds).
However you can get a wide variation of flexibility, as that is a completely different thing to tension, and that will affect the 'feel'.
So if you must insist on 45-105 i suggest looking for high flexibility strings.

To at least get comparative data on this and remove some of the variables, it seems that a standard testing rig could be defined that would tune a string to standard pitch and apply a known force at the mid-point of the string to see how far the string deflects.

Resistance to sideways deflection is actually primarily determined by tension, not scientific stiffness. Because the deflection is primarily fighting against the lateral components of the tension forces either side of the deflection point.
But i know what you are proposing and i agree, some kind of additional 'scientific stiffness' value for a string would be good to know.

 

[Phaidrus]

That is erroneous =) I am guessing this is the reason behind your desire for '45-105 with low tension'.
It is also somewhat unreasonable to insist on certain gauges and then want a wide choice of tension. Tension correlates fairly closely to gauge because string construction has many constraints so cannot vary much (assuming you want metal flatwounds).
However you can get a wide variation of flexibility, as that is a completely different thing to tension, and that will affect the 'feel'.
So if you must insist on 45-105 i suggest looking for high flexibility strings.

Having to face reality and physics I do agree, of course, that gauge correlates with tension. But my limited experience also tells me that what I named "authority" of tone correlates with gauge. There's no way, I think, to get an authoritative tone, in order to stage the laid back drama of a dub-reggae bassline, from a thin E or A string. To be sure the upper or lower limits of what may be considered adequate gauge are rather subjective. To each their own and mileage may vary. Given the above I'm looking for a relatively thick set of strings (45105) with the lowest possible tension and the highest possible flexibility. So far I've tried a number of sets and the one closest to the desired combination/outcome are the Dunlop SS flatwounds 45105 (on a Pbass fitted with a PV63 pickup).

 

[Jon Moody]

Having to face reality and physics I do agree, of course, that gauge correlates with tension.

This is why I'd love to see Dunlop release a tension chart for their strings, specifically the Super Brights. The core diameter (compared to traditional strings) is small, so they're incredibly flexible. But, how does that translate to actual pulling force on the neck? And, it is going to be inline with what we know from the few companies that have published their charts, or is it going to flip it on its head?

 

[ixlramp]

@Jon Moody
Potentialy unreliable summary of some quick research:

The mechanics property to measure is called 'flexural rigidity'.
This is measured by setting up a section of string as an 'end-loaded cantilever beam':
A short section of string is clamped at one end and is free at the other.
The free end is deflected perpendicularly by an adjustable force.
The amount of force needed to delect the free end by a certain small distance is measured.

From the protruding length of string 'L', deflection distance 'd' and force 'F':
Flexural rigidity = (F * (L ^ 3)) / (3 * d)

Because wound strings have non-homogenous structure the result for those would perhaps somewhat depend on what string length and what deflection distance is used. So comparing between companies would perhaps require them to agree on one particular experimental setup.
So perhaps not as straightforward as measuring 'unit weight' (for calculating tension data) which does not require experimental agreement. But even without agreement, it would be interesting for comparing strings within one company.

I am thinking a small core string would have more of its volume composed of wrap wire layers with air gaps, which would mean lower mass, and therefore lower tension, for a particular gauge.

 

[Phaidrus]

This is why I'd love to see Dunlop release a tension chart for their strings, specifically the Super Brights. The core diameter (compared to traditional strings) is small, so they're incredibly flexible. But, how does that translate to actual pulling force on the neck? And, it is going to be inline with what we know from the few companies that have published their charts, or is it going to flip it on its head?

Indeed, I'd like to see all string companies release tension charts! It probably does not take that much to do so. As of the Dunlop SS flatwounds (45 65 85 105), according to my subjective experience they have similar tension to the Fender 9050L set (45 60 80 100), the tension of which is also unknown, but the Dunlops feel more flexible. They have less tension than the DR Legend (45 65 85 105) and also feel considerably more flexible. They have way less tension than the Pyramid Gold (45 65 85 105) and feel way more flexible. This Pyramid set, especially the E and A strings, feel like cables. Judging from how much I have to adjust the truss rod on my Pbass, the aforementioned Dunlop flats probably have not much more tension than a equivalent set of, say, D'Addario XL nickel plated roundwounds (174.29lbs), so maybe 10 lbs more or so, which in fact is the tension of the GHS Precision Flats (45 65 85 105) set (184.6lbs). Dunlop call their flats "lower tension", would would also call the GHS PF so?

 

[ixlramp]

Dunlop call their flats "lower tension"

Interesting, they state that on the packets for the superbright and flatwound ranges for all gauges, even for the large gauges like .050-.110. Because tension is primarily determined by gauge, this suggests what they might mean by that is 'lower tension than the same gauges from other manufacturers'.
Perhaps they are using the word 'tension' to mean 'perceived tension' instead of 'actual tension' and are referring to the effect on feel of higher flexibility.

 

[Phaidrus]

Interesting, they state that on the packets for the superbright and flatwound ranges for all gauges, even for the large gauges like .050-.110. Because tension is primarily determined by gauge, this suggests what they might mean by that is 'lower tension than the same gauges from other manufacturers'.
Perhaps they are using the word 'tension' to mean 'perceived tension' instead of 'actual tension' and are referring to the effect on feel of higher flexibility.

Yes, they probably mean lower tension than the same gauges from other manufacturers, hence "lower tension" and not "low tension". Which appears to be technically possible. Take for example two equivalent string models by D'Addario: XL nickel plated roundwounds and NYXL nickel plated roundwounds, same gauge (45 65 85 105) and both with hex core wire. The XL have 174.29 lbs of tension while the NYXL 168.88 lbs. Why? I don't know but it goes to show that material, wrap wire profile and gauge are not the only parameters that determine tension. I'm not even mentioning (because they are different material) their stainless steel Pro Steel rounwound strings that have even less tension (159.94 lbs) for the same gauge. So Dunlop have probably come up with a formula that allows them to produce string sets with lower tension, I suppose.

 

[Levent]

TI flats if they were 45-65-85-105

I'd pay 150$ for a 45-105 TI Jazz Flats

 

[iiipopes]

If this has been said, please bear with me. The lightest flats I know about for raw tension figures are TI's and La Bella LTF's, or any custom set that may have something in the neighborhood of 35-90 gauges. Again, as above, it's all about the unit mass of the string at pitch. This opens a can of worms for core diameter and profile, wrap thickness, beveling of the edges or not, alloys (pure nickel will be more dense per unit than steel), wrap construction (gaps or not between windings), and other criteria. And as @michael_t pointed out, raw tension may or may not have anything to do with flexibility or feel.

 

[Phaidrus]

Now that you mentioned pure nickel vs steel as a factor influencing tension, I wonder what material exactly is "chrome nickel" used by Pyramid for their flats, which are abviously not pure nickel. Also why are D'Addario flats called Chromes - are they using a similar alloy?

Edit: Just checked, chrome nickel or nichrome is commonly 80% chromium and 20% nickel.

 

[iiipopes]

@Jon Moody
Potentialy unreliable summary of some quick research:

The mechanics property to measure is called 'flexural rigidity'.
This is measured by setting up a section of string as an 'end-loaded cantilever beam':
A short section of string is clamped at one end and is free at the other.
The free end is deflected perpendicularly by an adjustable force.
The amount of force needed to delect the free end by a certain small distance is measured.

From the protruding length of string 'L', deflection distance 'd' and force 'F':
Flexural rigidity = (F * (L ^ 3)) / (3 * d)

Because wound strings have non-homogenous structure the result for those would perhaps somewhat depend on what string length and what deflection distance is used. So comparing between companies would perhaps require them to agree on one particular experimental setup.
So perhaps not as straightforward as measuring 'unit weight' (for calculating tension data) which does not require experimental agreement. But even without agreement, it would be interesting for comparing strings within one company.

I am thinking a small core string would have more of its volume composed of wrap wire layers with air gaps, which would mean lower mass, and therefore lower tension, for a particular gauge.

This reminds me of my high school physics experiments. This is an adaptation of the math applied to structural concerns, such as the construction of buildings, bridges, and other infrastructure where the flexion has to be known so the supporting members of the structure can handle the load and will not break and fall down. Thanks for the math to help quantify perceived stiffness or flexibility of a particular string. Notice the flexural rigidity has as part of its equation includes the length ^3; while raw tension includes the mass ^2. The complication is that we really never flip a section of string by itself, only when tuned up to pitch on the bass, making it more difficult to really differentiate between tension and flexibility, when the string is on the bass, but the math is valid. Thanks, @Jon Moody !

It took decades from the invention of the electric bass as we know it for string companies to release tension figures, and even now, due to the costs involved in the acquisition of the measuring equipment and the sacrifice of product to make the measurements, not all companies release the figures. So it is no accident that D'Addario and GHS, two of the largest string companies, publish tension figures on their strings. Maybe in another few decades we will get to see published figures on flexural rigidity to go with the tension figures so we can combine the two to get a better idea of how a string may perform and feel on a bass.