Double Bass String tension versus 'bowability'

[Les Fret]

As an experiment I lowered all my strings a half step. I have the feeling that my bass is responding better to the bowing now. Strings seem to grab better and the overall sound is better I think.

Is it true that lower string tension results in better string grabbing? and does lowering the string tension 'remove' any wolf tones? on most basses these are around A. Is tuning the A string to G# eliminating that A wolf tone or any others? or does the wolf tone shift to G#?
I am not sure if it is only on my bass or if this is a general thing. I use D'addario helicore hybrids medium.

 

[Reiska]

I noticed the same since I have been messing around with tunings and strings a lot ( too much ) lately. I have now Spiro weichs on for this very reason. Wolfs diminished when I had extra low tension strings at higher height but didn`t go completely away ( b flat especially on my bass ). They remain on the same notes, no matter which tuning. It would be interesting to know the anathomy of wolf notes, what causes them? Havent started messing with tailpieces, afterlenght tunings or wolf eliminators on this bass yet.

Anyway, for me, lower tension = easier to bow.

 

[Pat Harris]

Every bass responds differently when factors are changed, but I've found that most basses have a sweet spot where the bass likes the tension to be (this could mean having lower tension strings raised higher or higher tension strings sitting a bit lower). This can sometimes work for or against a player depending on the stylistic requirements.

 

[sean_on_bass]

Just a curious question: Could the tension of the bow hair make-up for/offset the tension of the string, or are the two pretty much unrelated? Physics is not my strong point...lol.

 

[David Potts]

There may be at least four sets of variables to consider here. The first and probably least changeable relate to the design and quality of materials used to construct your bass. The second relate to the set-up such as bridge and string heights, sound post position, etc. The third is the string design, including tension and planned use. The fourth relates to the bow, its quality and hair tension, etc.

It is entirely logical that lowering the string tension will allow the instrument to vibrate more freely and increase the flexibility of the strings. Is this leading towards trying to change the sound and response of your bass when at normal pitch? In other words, are you less than happy with your bass right now?

The simplest experiment to try first is with bow tension. The hair should gently bend over the strings in order to drive them without crushing their relative freedom to vibrate. If the hair is too slack the sound is too woolly and lacks projection. If too tight the stick feels too stiff and unresponsive, the hair will skid and note starts lack bite. Try tensioning your bow so that when at its middle you press down three strings at once by using your maximum usual weight. If you are a French Bow user (which I am) this will be when the hair also contacts the stick. German bow? Check out your note starts, all over the length of the hair and in both directions. Then increase hair tension in half-turn steps and try again each time. Repeat the process by lowering the tension in half-turn steps and experiment until you optimise the bow tension for your current strings and set-up. Your age of hair and brand of rosin are other considerations.

Still not happy? Then you embark on a careful process of adjustment and /or change. Do you have height adjusters on your bridge? Lowering your strings even slightly can change response. Or raising the saddle at the bottom of your tailpiece. These are not expensive changes. Probably the next step is sound post adjustment but beware of the affect of "soundpostitis"on your sanity. Experimenting with different strings can become very expensive as I'm sure you know. Changing neck angles or belly thicknesses are big expensive operations that are usually not warranted.

Best wishes, DP.

 

[Les Fret]

Good points everybody! My main question however is whether the better 'grabbing' is caused by the decreased tension or the pitch change (absence of whole tones?).
If it is caused by the lesser tension I could experiment with a lighter string gauge.

And yes I have experimented with (French) bow hair tension, different strings, string height etc.
Problem is that I need a setup that works good for bowing and pizzicato. I probably wouldn't use steel or hybrid strings if I would only play arco. A dedicated 'bowing' string would work better but I like the sound and sustain of steels for pizzicato. And I need these hybrids for my magnetic pickup that I use sometimes use for higher band volumes.
Also for bowing less tension could be better but I like more tension for pizzicato. For bass set up the same thing; you have to find a compromise setup that works for both arco and pizzicato. So sometimes these two work against each other and all you can do is find a compromise or use two basses (which is not handy either if you use both techniques equally in the same session/song/piece).

 

[David Potts]

My instinct says the lesser tension will give better grab but I would not give up yet on the ideas of bridge height adjusters and sound post review before getting into strings. Lighter strings may not drive the bass as well and may still require sound post adjustment. Do you know of a good bass luthier?

Cheers, DP

 

[Les Fret]

My instinct says the lesser tension will give better grab but I would not give up yet on the ideas of bridge height adjusters and sound post review before getting into strings.

I have experimented already with string height with my bridge adjusters but it didn't make much difference. Strings are already on the medium to low side. Cannot have them lower because of string rattle. What can be done to the sound post you think in this regard? won't try this on my own though.

 

[David Potts]

From early on I have mostly done my own sound post adjustments as well as cutting and fitting them. In my own experience of "soundpostitis" very small movements of the sound post in the North-South direction (looking at the bass front) can have significant effects on even-ness across the four strings as well as the feeling of elasticity. My starting point is approximately the same distance as the post diameter below, and in line with, the foot of the bridge. This is also roughly 1 1/2 times the thickness of the belly. I feel there are a series of nodal points where the strings are even. Between them either strings 1 and 3 or strings 2 and 4 tend to come forward as the post is moved by tiny amounts. There is not a lot of distance between nodes. I go far enough South to feel the G string relax and resonate then start to experiment around there. The East-West movement of the post can also be used to balance string response and/or free up the E string but wedging the post by pulling too much to the East will tend to choke the G string response. I sense the elasticity by flexing each string to the fingerboard then all strings together at the 9th "fret", ie E B F# C#. I test the even-ness of response and "grab" with the bow by playing notes side-by-side across the four strings, descending fret by fret to the lower positions and open strings.

The experienced luthiers who see my above description may choose to correct and/or further educate me. The best set-up I have ever played on was by Arnold Schnitzer and Wil de Sola when I visited Wil a few years ago, and I would be proud and happy to achieve 90% of their result. Wil's basses all sang, both arco and pizz. Do you have any good bass specialist near you? A skilled luthier will be able to "read' your bass by its shape, thicknesses and materials of construction.

Hoping this helps,

DP