Double Bass Why no bridge adjusters in Europe?

[playbass0410]

But... is that just because you have a BETTER bridge? Because I had adjusters fitted to my bridge and there was no change I could detect. Same bridge, with adjusters, no change. I bet if you took the bridge you have now and fitted adjusters, nothing much would happen.

Well, my bass sounded great, so had no complains at all. But my teacher said "Get a massive bridge and it will improve", so did a friend of mine (luthier) so did another luthier, so finally I gave in.
The massive bridge did what was foretold.
I see no point why to add adjusters to this bridge so I cannot tell if there was no difference.

Here in Germany adjustable bridges as well as C-extensions seem to be not very popular amongst luthiers so this explains why they are not seen that often.

 

[Don Higdon]

If they were popular among players, they would be popular among luthiers.
You can't make them want adjusters by citing studies.
Vive la difference.

 

[robobass]

If they were popular among players, they would be popular among luthiers.
You can't make them want adjusters by citing studies.
Vive la difference.

I would say that's not necessarily true over here. Luthiers here are part of a close guild and the training is intense and uniform. If you ask them to do something that isn't exactly by the book their normal answer is "If I do this and you take the bass down to Pöllmann next year and they see what I've done and don't like it, they would have every right to badmouth me. Also, if it doesn't work then you would have every right to sue me."

When I met my local luthier he had fielded many requests for extensions, but was very reticent to build one. He had all kinds of ideas he'd been taught in school about how they increased tension, and could ruin a good bass. After hanging out with me for awhile he decided extensions might not be the antichrist of basses after all, and decided to pump up his chest and make one. It went well and now he's made many. All excellent.

There's something in the German psyche that makes them cautious and conservative, and want to stick with what they know. The disasters of the early and mid twentieth century history are still very much on their minds. This ain't no bad thing, though. Where would Europe be right now without Germany, after all?

The downside, of course, is stifled innovation. However good a bass idea is, you've got to find a luthier willing to go along with it and do it. Until a lot of luthiers do it successfully, then neither players nor luthiers will have first hand evidence that it is indeed a good idea. So, we look to you Americans to stand out on the plank and test the waters. If half a century goes by and you don't drown, then maybe we'll put a toe in the water too

 

[Badener]

Hi!

It ist true: In continental Europe many Jazz players play with adjustable bridges, but no classical player. And you never see a string extension, we prefer 5-string basses for the low end. Interesting to read: [Invalid or Expired Link Removed] .

A new type of an adjustable bridge is made in Austria and many bassists tell it improves the sound, maybe this is the future in Europe: [Invalid or Expired Link Removed] .

Thomas

 

[MostroDB]

Thank you for that MPM link Thomas. I've been thinking about something like that.

As the main advantage of such a construction I would see: a more even spread of the load, giving optimised contact between the bridge feet and the table; hence a more consistent distribution of the load on the table (over time), and (again, over time) less wear of the table, and also lower susceptibility to shaping errors. And it possibly improves acoustic transfer, but more importantly, because the load distribution on the table is more consistent over time (with the bridge tip moving up & down due to tuning & temperature variations [different expansion coefficients wood & steel]), the centre-point of the load will have a more constant distance from the soundpost.

What I mean by that is the following. Think of a stiff bridge (a bridge with adjusters has very limited free play, hence also stiff), with feet about the same thickness as the soundpost diameter, and the soundpost, say, 1.2 diameter below the bridge. If the bridge leans towards the tailpiece, the centre of the load will be on the bottom edge of the foot, so 1.2 SD above the soundpost. But if the bridge leans towards the fb, that load will be on the top edge of the feet, so typically 2.2 SD above the soundpost. Of course it depends on the instrument, but this may well have an effect on tone & playability. It may well contribute to variations people perceive in the behaviour of their instrument.

In my opinion, the main downside of such a gizmo is risk. I feel that you have to very carefully watch the inclination of the bridge, and make sure the centre line of the bridge (or the line between the contact point of the strings and the mid-point of the gizmo) always bisects the string breakover angle. If the tip moves too far away from that position, I think there is a real risk of the entire bridge tipping over (with a rather loud bang, and probably some ?minor? damage). This risk is increased if you lube the string notches w/ graphite. Whether or not something like that could happen, depends on the degree of freedom in the joint (not specified) & the thickness of the feet, but the animation certainly indicates that the tip can move beyond the edges of the feet. For a careful player, this risk is however perfectly manageable - but you should be aware of it. Minor downsides are extra mass & reduced structural strength.

My 2 cents on the main question of this tread (no adjusters in Europe): I don't use them because I hardly have any need for them, and I can only see downsides. They reduce structural strength of the bridge (am I the only one having seen the maple cracked round the pins?), stylistically they are quite an outstep from the conventional appearance of a bridge, and they add mass. The added mass, however, is not necessarily a bad thing, some instruments benefit from that, while others suffer from it. But if an instrument benefits from it, I feel there are more elegant ways of adding mass. And then there is this: why would you fuss about the micro-tuning of the bridge & ornaments, and then slap a few chunks of ugly metal on that same bridge?

The up side is of course easy adjustment of string height. I rarely need this, but if I want to go higher I just slide 1mm or 1.5mm shims of birch (aircraft) plywood below the feet. That conforms perfectly to the shape of table & feet, and is just about as easy to do.

Anyway, it all remains a subjective choice - as everything in music.

Edit: Thomas, thanks for the Forschung link too. Interesting reading, but while the author appears to suggest scientific authority, I still have quite a few question marks on method & consequently conclusions. Nevertheless, a valuable contribution. Particularly the sound samples are an ear-opener.

 

[robobass]

Thank you for that MPM link Thomas. I've been thinking about something like that.

As the main advantage of such a construction I would see: a more even spread of the load, giving optimised contact between the bridge feet and the table; hence a more consistent distribution of the load on the table (over time), and (again, over time) less wear of the table, and also lower susceptibility to shaping errors. And it possibly improves acoustic transfer, but more importantly, because the load distribution on the table is more consistent over time (with the bridge tip moving up & down due to tuning & temperature variations [different expansion coefficients wood & steel]), the centre-point of the load will have a more constant distance from the soundpost.

What I mean by that is the following. Think of a stiff bridge (a bridge with adjusters has very limited free play, hence also stiff), with feet about the same thickness as the soundpost diameter, and the soundpost, say, 1.2 diameter below the bridge. If the bridge leans towards the tailpiece, the centre of the load will be on the bottom edge of the foot, so 1.2 SD above the soundpost. But if the bridge leans towards the fb, that load will be on the top edge of the feet, so typically 2.2 SD above the soundpost. Of course it depends on the instrument, but this may well have an effect on tone & playability. It may well contribute to variations people perceive in the behaviour of their instrument.

In my opinion, the main downside of such a gizmo is risk. I feel that you have to very carefully watch the inclination of the bridge, and make sure the centre line of the bridge (or the line between the contact point of the strings and the mid-point of the gizmo) always bisects the string breakover angle. If the tip moves too far away from that position, I think there is a real risk of the entire bridge tipping over (with a rather loud bang, and probably some ?minor? damage). This risk is increased if you lube the string notches w/ graphite. Whether or not something like that could happen, depends on the degree of freedom in the joint (not specified) & the thickness of the feet, but the animation certainly indicates that the tip can move beyond the edges of the feet. For a careful player, this risk is however perfectly manageable - but you should be aware of it. Minor downsides are extra mass & reduced structural strength.

My 2 cents on the main question of this tread (no adjusters in Europe): I don't use them because I hardly have any need for them, and I can only see downsides. They reduce structural strength of the bridge (am I the only one having seen the maple cracked round the pins?), stylistically they are quite an outstep from the conventional appearance of a bridge, and they add mass. The added mass, however, is not necessarily a bad thing, some instruments benefit from that, while others suffer from it. But if an instrument benefits from it, I feel there are more elegant ways of adding mass. And then there is this: why would you fuss about the micro-tuning of the bridge & ornaments, and then slap a few chunks of ugly metal on that same bridge?

The up side is of course easy adjustment of string height. I rarely need this, but if I want to go higher I just slide 1mm or 1.5mm shims of birch (aircraft) plywood below the feet. That conforms perfectly to the shape of table & feet, and is just about as easy to do.

Anyway, it all remains a subjective choice - as everything in music.

Edit: Thomas, thanks for the Forschung link too. Interesting reading, but while the author appears to suggest scientific authority, I still have quite a few question marks on method & consequently conclusions. Nevertheless, a valuable contribution. Particularly the sound samples are an ear-opener.

I'm pretty much on board with everything you say, excepting a few things:

1. I don't think aluminum adjusters add any significant mass. I do however think adding mass in the legs is usually a bad thing. It may be psychoacoustic, but any bass I've played with brass adjusters just felt horrible.

2. I think adding 1.5mm shims under the feet would indeed compromise surface contact. At least I bet a lot of respected luthiers would have this opinion, and once adjusters are installed, then adjustments can be made without taking down the setup.

Your discussion of bridge angle and breakover angles is spot on, but it doesn't apply only to adjustable bridges. If the north and south side breakover angles differ significantly then you've got an unstable system, even with a solid bridge. Of course, if a solid bridge collapses under tension, then there is less damage to the top. I've got nasty scars on my Geiger from knurled wheels.

But still, players should be instructed by their luthiers to keep an eye on this themselves. Bridges of both types can warp, get bumped, or simply drift. One time, my stand partner and amateur luthier put my Pfretchzner bass up on the table and said "Do you realize that your bridge is so crooked that your E is 1/4" longer than your G? I sit with you every day, and you play in tune, so you have adjusted, but wouldn't it be better to have all four strings the same length?" I couldn't really disagree...

 

[MostroDB]

Robo, thanks for your feedback.

I think we're aligned on the added mass, just everybody his on what is 'significant'.

The breakover bit was meant to apply to the ankle gizmo, but the physics of course apply to any bridge. It's just that if you put the joint in, you take away the positioning force that the feet give (normally tp-ward, causing bridge warpage over time) and the whole system becomes even less stable, only being held by the friction forces between strings & bridge. It's like balancing a pencil on its sharp end.

People are always extremely concerned about the fit between the feet and the table, and I too think the fit should be excellent, in order to reduce surface pressure & wear. And I actually feel an ankle joint, like the MPM one, can give a practical improvement by distributing the load & evening-out the surface pressure - but at a manageable risk.

I knew shims are considered blasphemy, but anyway, I started by mentioning them - so here we go.
With a total breakover angle of 34° (so 73° between the strings and the bisector, on each side) and 120 kg total string tension, you have 35 kg downforce on each foot. The plywood I'm talking about is 'Isensee Birke 1.5mm', of about 30 years old, which you can cut with normal scissors. Bending it between my fingers, perpendicular to the grain of the outer layers, I estimate I would at best need 100 g to bend a strip to the curvature of a bridge foot. I just tested a strip using a bridge and the weight of an upside-down bottle of washing-up liquid, weighing about 350g, gives a pretty perfect fit. So I am quite confident that applying 100x more weight will leave no significant gap & is good enough for me. If the bridge fits to the table well, it just moves up by 1.5 mm (or 1 mm), and the plywood is nicely flat in-between the two. There will be microscopic gaps, but there are always microscopic gaps between any fitted wooden bridge foot and the table, if fitted by mechanical means, no matter how skillful & patient the luthier. (With a molding approach you can improve the fit, but even then you have microscopic gaps - but to me they really are of no concern, acoustic or otherwise.)

Here again - everybody his on what is 'significant'.

Btw, you don't need to take the setup down to slide shims in, just release tension, like with an adjustable bridge, but indeed quite a bit looser. I pull off the 2 outer strings, but leave the middle ones on, and indeed, if your soundpost is loose it may drop. Then just grab a leg, thumb towards strings, index below the arch & side of your hand resting on the table. Close your fist & if your hand is big enough your index should lift the bridge under the arch while the side of your hand pushes on the table, & just slide it in. Both sides, check positioning & tune-up. I just did it in under 10 minutes, including tuning. Perfect fit. Only my strings are a bit high now...

 

[playbass0410]

I had bridge adjusters, payed a fortune for let a luthier cutting me a really decent massive bridge and ... after intense tests went back to the original much cheaper bridge with alu adjusters.

Why?

Well the massive bridge had more meat in the bass area while sounding darker and more mellow. Amplified it had in the bass region of 80-150Hz two resonances that I had to tame via notch filters - so it was more problematic to amplify.

The bridge with adjusters had less fundamentals but more brightness and it was easier to amplify. As amplification is my personal use case I simply got better and more transparent results with the bridge with adjusters.

Interestingly enough my personal experience absolutely correlate with the 2000e-Brown_BHA_CD.pdf Forschung study posted above.

Anothere experience is - as I also had the fingerboard completely reworked, the whole mechanical setup changed. It took me about 4 weeks to come to the perfect string height. The adjustments in the beginning were bigger steps, at the end it where very subtle changes (up-down-movements). Now I do not move the adjusters anymore - they settled at the perfect height. With the cut bridge this process is much more difficult, as you can cut away but not add height again beside adding shims.

Albeit I like massive bridges more in terms of aestetics, the bridge with adjusters gave me the better overall tonal result for my use case plus easier handling. If I would bow in a classical setup, the massive bridge would be the better tonal choice.

So in spite of being located in Germany I do prefer the bridge with adjusters for amplified Jazz playing.

 

[DoubleMIDI]

If you want shims to raise the bridge I would prefer several layers of hardwood veneer. You can stick them together with a glue stick first and they will easily fit the curvature.
If you know what height you want for a longer time you can use a better type of glue. Glue the sheets of veneer together under pressure to get the desired shape. (Use plastic foil between top and veneer to avoid getting glue on the top, remove the foil later when the glue is dry.)

Softer wood might compromise the tone quality, specially if it is so soft (and also thick) that is gets into shape under pressure.

Just my idea to that topic...

 

[Eric Hochberg]

Frank Tate, jazz bassist with Buddy DeFranco and many others has cork under his bridge and adjusters. Swears by the sound using the cork shims.

Just for the record, I had adjusters put on my bass 33 years ago, and the bass has been played hard with the same bridge all that time and still going strong. No problems. I think too big a deal is being made about using/not using them. They fulfill the function they are designed for very well and I'm not convinced there are any significant drawbacks, just benefits.

 

[MostroDB]

Yes, after thinking it over a bit more, I must agree. Standard adjusters are easier for adjusting height than shims, so they allow you to arrive at that 'perfect height' far easier. But once you are there, and if you use the same strings for a long period, and if the climatic conditions don't change that much, you don't need them anymore for height adjustment - but they are still there. And some basses/applications benefit from that, while others suffer.

That's one of the problems I had with the forschung: just 1 instrument.

On the hard/soft: birch is not soft, it has properties not dissimilar to maple. It's just that a thin strip is easy to stretch & compress across the grain. You should lay the grain in the same direction as in the table.

On the strength of a bridge with adjusters: sure, if you keep the bridge well positioned, it will last forever. But if you don't, you may get cracks in the area where the holes for the pins are drilled. Maybe that's a good warning (if you see it), a solid bridge tends to break without warning.

But indeed we shouldn't make a big deal out of it, it remains a personal choice.

 

[Don Higdon]

Frank Tate, jazz bassist with Buddy DeFranco and many others has cork under his bridge and adjusters. Swears by the sound using the cork shims.

Just for the record, I had adjusters put on my bass 33 years ago, and the bass has been played hard with the same bridge all that time and still going strong. No problems. I think too big a deal is being made about using/not using them. They fulfill the function they are designed for very well and I'm not convinced there are any significant drawbacks, just benefits.

Not to contradict Frank, but he has an awesome bass that would sound good regardless of how well it was set up.

Agreed. Properly designed and installed, a bridge will go for decades, with or without adjusters. It's not worth going to war.

 

[Jazz Ad]

Given the price of a set of strings around here, we barely ever change them. We have seasons but the climate isn't too extreme, double bass necks don't move much anyway.
In short, I can't think of a reason to have height adjusters installed.

I had adjusters put on my bass 33 years ago, and the bass has been played hard with the same bridge all that time and still going strong. No problems. I think too big a deal is being made about using/

How many times did you turn the wheels in 33 years?

 

[Eric Hochberg]

In short, I can't think of a reason to have height adjusters installed.How many times did you turn the wheels in 33 years?

I turn them as needed, which can be quite often, especially during the change of the seasons, if only a quarter turn at a time. If you don't ever need to raise and lower your strings, then you obviously don't need them. In very changeable climates, they are a big help.

Another thought, if while bass shopping I liked the tone of a bass with a solid bridge, but then did not like it with adjusters added, I would move on to a different bass. That's how necessary adjusters are to me.

 

[MostroDB]

Hooked?

 

[Chris Fitzgerald]

In short, I can't think of a reason to have height adjusters installed.How many times did you turn the wheels in 33 years?

With my main bass, which is kept in a humidity controlled music room in my house, I use my wheels in the fall/winter change every year, and then again in the spring/summer change each year as well. Except for those two seasonal changes, that bass is so stable it can even hold tuning for weeks at a time.

With my backup bass, which lives in my office at the university where there is *no* humidity control whatsoever, I use the wheels every couple of weeks. The humidity here in the Ohio valley is a rollercoaster. In the summer, the hygrometer can read in the 80-90% range, and in the winter it can get as low as 15%. Higher humidity makes the strings higher, and lower humidity lowers them. I try to control the office humidity in the winter, but since the system mixes inside and outside air, it's really difficult.

I've even played a few gigs where I had to adjust in the middle of the gig when a big storm/pressure system came in after the start of the gig.

 

[MostroDB]

Well, yes, with such swings in humidity I can clearly see a point for adjusters. But I don't get that, where my basses now live they have, say, 55% +/- 15% (with the lows in winter & the highs in summer). That gives me the luxury of not needing height adjustment, so my choice would be on other grounds - and then I choose not to have them.

It of course also remains a personal choice how much variation in height you choose to accept: when is a movement up (or down) significant enough to warrant the hassle? Or can you just play with it, like people did before adjusters became common? There's a cultural component that may also be relevant.

Anyway, it is clear that adjusters reduce the hassle (compared with sliding in shims or mounting your summer bridge), so you can accept a lower psychological tolerance. 'Enhanced flexibility' is another way of saying it, but at a price.

 

[Don Higdon]

In short, I can't think of a reason to have height adjusters installed.How many times did you turn the wheels in 33 years?

Whenever I change strings with differences in tension. Anima and Spirocor mittels, for example.

When the bass top arching changes with the season.

 

[Jake deVilliers]

Given the price of a set of strings around here, we barely ever change them. We have seasons but the climate isn't too extreme, double bass necks don't move much anyway.
In short, I can't think of a reason to have height adjusters installed.How many times did you turn the wheels in 33 years?

Around here, even the ply basses need some adjustment when the cold, dry air comes over the Rockies from Alberta. It happens most winters - we go from 55% humidity to ~20% in a hurry and ALL the basses change size...

They're also very good to have if you travel at all. Here at the beach summer humidity is around 50% whereas in Idaho and Wyoming it will be ~25%. Nothing like playing a festival with your strings banging on the fingerboard to make you wish you had adjusters!

 

[MostroDB]

Can we please agree this horse is now officially dead so that we can stop flogging it (and each other)?

I think we all agree that wood absorbs moisture, so if a bass is exposed to swings in humidity, adjustments may be required, and similarly if you put on different strings. And that adjusters are good for adjusting. But maybe also that if you don't need to adjust, you don't need adjusters.

And then maybe we can finally agree that the Americas have long north-south mountain range, particularly in the northern hemisphere perpendicular to the prevailing winds, which Europe does not have. There are almost certainly geometeopsychosociographological reasons for the choices we make, but we can all choose for ourselves and we don't need to go to war over it.