Double Bass 3/4 vs 4/4 gauges- is there a difference?

[Chris Fitzgerald]

Is everybody perceiving tension? I mean, well.. anybody? I always thought when I raised the adjusters, the bass just got a bit louder. Not from tension but from more clearance and room to bloom... Seriously, Chris, you should think about trying some good guts.

Tried them more than once and love the way they sound with other people playing them. But for whatever reason, I like a stiff, bright string, so I'm a steel/synthetic player I guess. No worries, though. It's good to learn more about the physics behind the feeling, even if it doesn't change the feeling.

 

[Eric Hochberg]

Chris, drurb, on the pizz digging: yes, agreed, for a big sound you need to be able to grab the strings well, hence some distance between the fb and the strings (clearance). But that has everything to do with plucking technique, not with tension in the strings, which I thought was the topic of this tread.

This is not what they are talking about. I know exactly what they mean, the percieved tension in the strings as you pluck and how raising and lowereing the strings changes that.

Mostro, your profile isn't filled out. Are you a double bass player who plays a lot of pizz? If so, I think you would understand this.

 

[MostroDB]

Eric, as you know exactly what they mean, can you please define what they are talking about (for a simple physicist who has played db for over 30 years)?

 

[Eric Hochberg]

Eric, as you know exactly what they mean, can you please define what they are talking about (for a simple physicist who has played db for over 30 years)?

I think I did define it in my post above - ("the percieved tension in the strings as you pluck and how raising and lowering the strings changes that"). To be more precise, lower the strings for less perceived tension, and raise the strings for more. I'm not going to reread this thread again, but I believe you don't have bridge adjusters? I think if you get them, you might find out what we are talking about, assuming you play jazz style pizz.

 

[William Hoffman]

The TI Spiros were originally made for large orchestra basses. These instruments often use a low B string (at least in europe) where they need a larger body and a larger string scale.
The Belcanto is more of a soloist string. These players don't need low notes, large instruments and long scales.

String manufacturers make the strings for the market, no or very small market, no strings.

That's insightful about BCs. Spiros are for a huge market, for orchestra, jazz, arco, pizz, solo, 5ths tuning, in various sizes and gauges. Belcantos are for a smaller market.

The truism is logical. But the string maker who makes a wide offering of great strings without effectively communicating the full range of their application and playing possibilities to all the bassists who would buy them or to the dealers who would sell them has to be overlooking something.

 

[MostroDB]

I think I did define it in my post above - ("the percieved tension in the strings as you pluck and how raising and lowering the strings changes that"). To be more precise, lower the strings for less perceived tension, and raise the strings for more. I'm not going to reread this thread again, but I believe you don't have bridge adjusters? I think if you get them, you might find out what we are talking about, assuming you play jazz style pizz.

No, you don't explain What it is, you only say When you perceive this elusive tension (which is not the tension in the string), and how it varies.

I've gone back to Chris' descriptions and I think I know exactly what he means. If you pluck a string, the amount of resistance (Force) the string gives before your fingers release it, and Distance they travel before the string is released, depends on the clearance between strings & fb. A higher clearance invites better digging, which makes plucking harder and more tiresome, but it gives a better defined, stronger sound (as Chris says "bigger and more "pointed" on the front of the note"), while a lower clearance is lighter to play, but gives a weaker sound (more like a bg). And there's a personal choice to be made here (how do you want to pluck your strings on this bass?), which is very closely related to your set-up, depending on personal preferences (including how tired you are). The preferred height also depends on the string tension and elasticity, but of course those do not change if the height is adjusted.

The product of Force x Distance is the Work your fingers have to deliver, and how quickly they do that determines the Power they're delivering, and how long it takes before your underarm start to hurt and blisters appear. Of course the Tension in the string, and the elasticity of the core, but also the string clearance, determine the Force that your finger feels from the string & have to deliver.

I have had (copper) adjusters in 2 bridges and I have removed them from both (new feet). They did not make me perceive tension, but they did make me perceive what I describe above.

Thinking it over, I can see why you would want to be able to adjust this clearance easily (particularly indeed when getting tired). So far I have taken the approach to set the instrument up the way I like it (I have several bridges for each of my basses), and then just played it the the way it is. I can do this because I stick to the same strings, and because my humidity stays largely constant. But I can see why you could get hooked to easy adjustability - because I too get tired.

If you want easy adjustability of this set-up component, however, adjusting the fb might be preferable to adjusting the bridge height. Adjustments could be done by just a single nut below the end of the fb (with a trussrod, or maybe just a tension/compression beam to the heel), and you can do them without (significantly) re-tuning the instrument, so it can be done a lot quicker and you don't need to worry so much about bridge orientation. You may also want to adjust your fb after significant bridge height adjustment. Potential downsides could be: extra load on the fb-heel glue seam & different fb sound (particularly when slapping, but there this issue does not apply anyway?).

Does anybody have any views if adjustable fingerboards on double basses would be popular? Has it been tried? Should this get a dedicated thread?

 

[Eric Hochberg]

If you want easy adjustability of this set-up component, however, adjusting the fb might be preferable to adjusting the bridge height. Adjustments could be done by just a single nut below the end of the fb (with a trussrod, or maybe just a tension/compression beam to the heel), and you can do them without (significantly) re-tuning the instrument, so it can be done a lot quicker and you don't need to worry so much about bridge orientation. You may also want to adjust your fb after significant bridge height adjustment. Potential downsides could be: extra load on the fb-heel glue seam & different fb sound (particularly when slapping, but there this issue does not apply anyway?).

Does anybody have any views if adjustable fingerboards on double basses would be popular? Has it been tried? Should this get a dedicated thread?

Do you mean bringing the neck back and forth in the block, or changing neck angle, to change the fingerboard to string height? It is done on some EUBs and removable neck systems for double basses. Patrick Charton's design does this. http://www.patrickcharton.com/en_EN/index_b21.php

 

[MostroDB]

Thank you for that link. I knew changing the neck angle is done elsewhere (see for instance http://www.freepatentsonline.com/7816592.pdf), but I hadn't seen it on acoustic double basses. Patric Charton's approach looks effective, but a bit ugly & not very attractive to me. (I would prefer something with a less obtrusive tension rod.) Apart from the way it looks, another downside would be a significant tuning cycle. The same applies to sliding the neck (out or in), which would be possible with various existing detachable neck systems. None of these systems will give you a quick and easy adjustment - they are all aimed at beheading your db.

No, that is not what I mean. I mean adjusting the straightness (or curvature in the length-wise direction) of the fingerboard. Its what your luthier does when he is shaping your fingerboard. As you probably know, it is not straight, but slightly curved to find an optimal compromise between sufficient angle between the string and the fb at the contact point (where you press the string onto the fb, particularly [DEL]higher up[/DEL] closer to the nut), and an action low enough to provide easy playability throughout the range. The systems you mentioned do not adjust that in any way, and they may actually cause a mis-fit between string height and fb straightness.

Now with db necks being as stiff as they are, I wouldn't dream of putting a conventional truss rod in a conventional maple-ebony neck (it might just be a fingerboard removal tool or neck splitter, at any rate it requires great forces and it is not something you do during a set), but the free part of the fingerboard can bend up & down quite easily for up to a cm. And when you get tired and want a little less clearance for your right hand, you could push that part of the fb up a bit. Or alternatively you start with a more curved fb which you pull down in the beginning, and you release the tension for the end of the fb to come up. With enough overstand at the heel, all that's required is a rather unobtrusive tension/compression rod underneath the free part of the fb, between the heel and the end of the fb. Or maybe a truss rod below the free part of the fb, which would be like the lower half of a dual truss rod system as proposed by Chapman in his US8183447.

It will also be a compromise, obviously if you deform the fb too much you will draw a hump near the octave, or push a dent, but for small deformations of a couple of mm I don't think that will be an issue. And for such small deformations (like you achieve with your adjustable bridge), you may not need to re-tune, so it would take just a fraction of a second. You might just have a 2-position switch.

More broadly speaking, it would also allow more flexibility in the set-up, as I outlined in one of my earlier posts.

 

[iiipopes]

It is an issue. When I got my CCB (long story, in short, 1-I had limited cash, and 2-I wanted to set it up myself [30+years of tinkering with other instruments], even though the rough camber of the fingerboard from the factory was pretty good, I had to take a combination of my modeling planes and sandpaper and touch up spots and get it to where it needs to be.

Hold the string to the fingerboard near the nut and at the end of the overstand, and sight it with a bright light. What you see should be a slight, but regular and defined crescent. If it isn't, at any point along any string, then it will need dressing to bring the relief into line. It isn't easy. It isn't fun. It's messy. But if you want low string action, especially for jazz pizz, it is necessary.

A couple of millimeters? That is way too much slop. Proper camber is in the thousandths of an inch, almost as fine as necessary for telescope optics. But it can be done with patience, and is done every day by skilled bass luthiers nationwide.

Unlike an electric bass, with a long neck that is thinner and more prone to relief and warp than a double bass neck, no reinforcing rods are necessary: a good neck with proper grain orientation (as evidenced by the "classic" tiger striping of the necks of superior instruments) and with a good, thick ebony board to aid the stability of the neck, is good enough, and has been for at least 400 years.

The bottom line: unlike an adjustible truss rod on an electric bass guitar, the construction theory of classical double bass does not lend itself to the adjustments you describe, if for no other reason than the dynamic aspect of the top, which also flexes with the downforce tension over the bridge, is also an issue with its own variables that also have to be balanced.

Now, you're theories are intriguing and may have great application in the field of solid body electric upright basses: being able to adjust an EUB as you describe for different EUB applications is something that would have appeal for those who have progressive and diverse musical interests.

I've never considered an EUB, but with the progressive ideas you describe, I'd love to see one constructed along those lines. I think I have some gigs that could make good use of such an instrument.

 

[MostroDB]

That is fair comment on playability. While the accuracy in the order of thousandths of an inch (typically 1/4th of the thickness of a human hair) might be required for the rugosity of the fingerboard, I was proposing a smooth bending, with an amplitude of, say, 2mm at the end of the fingerboard, that is otherwise shaped "perfectly". For that dimension such an accuracy is certainly not required, otherwise you couldn't touch your fingerboard during playing (that will cause more movement). But your comment is fair in that it remains to be seen how much movement at the end is acceptable - again a subjective choice.

Only the free bottom part of the fb will be deformed, and this is the part where the contact angle will be biggest anyway, hence is least sensitive to inaccuracies. Indeed, to get an indication of what I'm talking about, just press a string down to the fb, while at the same time grabbing the bottom of your fb at the very end, and move the lot up & down to judge the impact of this deformation. A movement down may be more detrimental than a movement up, but still this is not a real test. A better test (of a movement down) would be to take a piece of twine and tie that over the top of the end of the overstand, and round the back through the C-bouts. Tie it down with a tension sufficient to pull down the fb end by 2mm (rig a loop for tensioning below the fb) - and play to judge the impact. I think one can live with that, certainly if it would come with a perceived advantage.

Anyway, I was only suggesting this approach as an easier and quicker adjustment (compared to the existing practice) of the string height in the grabbing area, for relief of the right hand, as there appears to be a need for that. Anybody is free to try, I don't belief it is patented, so it could be commercialised too. However, there appears to be little interest for it, at least not in this offering. That's fine, I don't need it either - I just play the instrument as I've set it up.

BTW: the pressure on the top (or, in fact, on any part of the body) is not influenced in any way by the tension/compression rod (or, alternatively, truss rod assembly) I proposed, nor did I propose a truss rod in the neck.

 

[Sam Dingle]

I compared the 3885.1 3/4 and S42 4/4 G strings and the 3/4 strings are about 6 cm shorter than the 4/4.
My 15 year old S42 E is 168.7 cm (66.2 inches) long.

My bass is 109 cm and was strung initially with S42 by the luthier who build the instrument.
I would never try 3885.1 3/4 on my instrument, even the S42 were hard for me to play for several hours. The 3/4 strings would have even more tension if they fit. But maybe you are better trained than I was.
The 3/4 may fit on a 4-string 109 cm bass, but I'm rather sure they would be a bit too short for my 5-string.

Can you or anyone think back and let me know what is shorter, the playing length or the silks? I have 4/4 weich and what I thought were 4/4 mittles but the silk is about 3 inches shorter on the silks but the playing length is the same. Both strings are uncut. Would this confirm that my mittle is a 3/4 size and not a 4/4?

 

[DoubleMIDI]

Have a look in my Dropbox (Link below). I found that comparison of Spiro string lengths somewhere and thought I should save that for others (and me).

The problem is, that you can never be sure how long the silks are spun.

But coming back to your question, my about six year old Spiro Weich 3/4 D is 134 cm from ball end (ball itself excluded) to beginning of the pegbox silk under tension, my about 30 year old Spiro Mittel 4/4 D is 137,5 cm from ball end (ball excluded) to the beginning of the pegbox silk, maybe more if under tension.

Maybe that helps a bit. The only real test is measuring the tension. You can do that with an electronic suitcase scale (at least for 40 Kg) in the underlength or replacing the tailpiece, but bridge friction and bridge angle (which influences the scale length) might influence the result.
That's basically how I measure the string tension, but I built something so I can still use my bass with more than a single string...

 

[Sam Dingle]

hmmm that does nothing for me. The playing lengths are exactly the same on each string. I'll just forget about it haha

 

[DoubleMIDI]

Did you measure ball end to the start of pegbox silk?
The playable length of the string means nothing. The total length of the string is important. And the start of the top silk is the most meaningful if you are not sure if the string was cut or not.

You can easily calculate any length from the data of the Spiro string length document (another Excel I found out) in my Dropbox. Link to folder in my signature.
This data matches my strings rather well.

 

[Sam Dingle]

Have a look in my Dropbox (Link below). I found that comparison of Spiro string lengths somewhere and thought I should save that for others (and me).

The problem is, that you can never be sure how long the silks are spun.

But coming back to your question, my about six year old Spiro Weich 3/4 D is 134 cm from ball end (ball itself excluded) to beginning of the pegbox silk under tension, my about 30 year old Spiro Mittel 4/4 D is 137,5 cm from ball end (ball excluded) to the beginning of the pegbox silk, maybe more if under tension.

Maybe that helps a bit. The only real test is measuring the tension. You can do that with an electronic suitcase scale (at least for 40 Kg) in the underlength or replacing the tailpiece, but bridge friction and bridge angle (which influences the scale length) might influence the result.
That's basically how I measure the string tension, but I built something so I can still use my bass with more than a single string...

Did you measure ball end to the start of pegbox silk?
The playable length of the string means nothing. The total length of the string is important. And the start of the top silk is the most meaningful if you are not sure if the string was cut or not.

You can easily calculate any length from the data of the Spiro string length document (another Excel I found out) in my Dropbox. Link to folder in my signature.
This data matches my strings rather well.

I did not measure the silk that goes around the peg, both strings (right after the ball plus playing length) measured to 135 ish. But the peg end silk on the mittle is clearly shorter than the weich silk.

So I assume they are both the same length?

 

[DoubleMIDI]

I haven't put down my 3/4 Weich either and I have cut these strings for my EUB, so putting it down won't help.
Damn, get that file, read it, add lengths as needed and compare with your strings. The start of the pegbox silk might vary by half an inch, but that would be clear enough IF MEASURED FROM THE BALL END.

Another method, but less precise:
If you need to tune down by a halftone to get the same tension then it is a 4/4, if you need to tune down by two halftones, it is a 3/4, but only at the same scale length.

 

[stefaniw80401]

Is there a difference in gauge thicknesses between the S42 and 3385 strings?

 

[Sam Dingle]

Ok so to confirm the Mittle E I have is notably shorter than the stark E which only comes in 4/4, so I think I have a 3/4 set. I will check and see if the 4/4 set feels any looser on my 7/8 bass.

 

[DoubleMIDI]

Tension difference between 4/4 Stark and 4/4 Mittel is larger (about a whole tone) than what can be evened out by detuning the Stark by a halftone (which is about the difference between Mittel and Weich). So a 3/4 Mittel should be more tension than a 4/4 Mittel but less than a 4/4 stark.
For a more flexible recalculation of tension by detuning use my formulas.html file in a JavaScript enabled web browser. You need to download that file first from my Dropbox and then open the file with a web browser. No need to enter any formulas, just the data which you can get from the excel file of manufacturer data.

 

[Sam Dingle]

Tension difference between 4/4 Stark and 4/4 Mittel is larger (about a whole tone) than what can be evened out by detuning the Stark by a halftone (which is about the difference between Mittel and Weich). So a 3/4 Mittel should be more tension than a 4/4 Mittel but less than a 4/4 stark.
For a more flexible recalculation of tension by detuning use my formulas.html file in a JavaScript enabled web browser. You need to download that file first from my Dropbox and then open the file with a web browser. No need to enter any formulas, just the data which you can get from the excel file of manufacturer data.

I have one more question (forgive me I am not good with the drop box stuff. Can't figure it out).

I have confirmed I have 4/4 mittles already on my 7/8ths bass. The string length is 43.5. I would like SLIGHTLY less tension on the ADG strings than what is on there right now. Sticking with spirocores would that mean trying the 3/4 weich or the 4/4 weich?

During typical discussion I would assume the 3/4 weich are a minor step down and heavier than the 4/4 weich but I'm not sure if putting the 3/4 weich on such a large instrument would actually make them more tension than the 4/4 mittles.