Double Bass String change has put my intonation all over the place.

[jazzyvee]

I'm still a beginner and for a while now the first two fingered notes on my A,D,G strings on my EUB especially the A on the G-string have an unpleasant and uncomfortable buzz under my fingers when playing that note. I don't get it anywhere else except those strings and it does not seem to appear on the output that I can hear in my amp.
But I decided to re-string the bass with some D'addario Low Tension strings (no idea what the model name is), that were previously on my old acoustic double bass when I had it set up. I removed them when I sold it as they were expensive and hardly used.

Anyway these strings are much more flexible, less tension and more comfortable under my fingers. However, now my notes are not where they were previously like the intonation has gone off. Should I angle the bridge to adjust the speaking length of the string in order to get the notes to work or should I just be re-learing the intonation and keep the bridge where it is ?


At the moment I am tempted to put the previous strings back on and live with the buzz.
Any advice will be gratefuily received.

 

[Videojunkie]

Check your bridge to make sure it hasn't moved when you changed the strings.

 

[bherman]

Check your bridge to make sure it hasn't moved when you changed the strings.

Agree with this - not sure what kind of bass your EUB is, but if you just changed the strings and intonation is off, then the bridge is likely to be out of alignment. Also make sure that the bridge is vertical, and that the top of it isn’t tilted either towards the fingerboard or tailpiece. If you post some photos, we can take a look at it.

 

[Francois Blais]

In fact, a bridge should be asymetrical.
One side should be perpendicular to the feet, and that's the side towards the tailpiece.
Look at this:

 

[Francois Blais]

 

[Wasnex]

I'm still a beginner and for a while now the first two fingered notes on my A,D,G strings on my EUB especially the A on the G-string have an unpleasant and uncomfortable buzz under my fingers when playing that note. I don't get it anywhere else except those strings and it does not seem to appear on the output that I can hear in my amp.
But I decided to re-string the bass with some D'addario Low Tension strings (no idea what the model name is), that were previously on my old acoustic double bass when I had it set up. I removed them when I sold it as they were expensive and hardly used.

Anyway these strings are much more flexible, less tension and more comfortable under my fingers. However, now my notes are not where they were previously like the intonation has gone off. Should I angle the bridge to adjust the speaking length of the string in order to get the notes to work or should I just be re-learing the intonation and keep the bridge where it is ?


At the moment I am tempted to put the previous strings back on and live with the buzz.
Any advice will be gratefuily received.

It will take time for you to relearn the intonation of the instrument. The bridge should remain properly positioned.

 

[jazzyvee]

Check your bridge to make sure it hasn't moved when you changed the strings.

I changed the strings one by one to minimise the chance of movement. is not leaning towards nut or tailpiece.

 

[jazzyvee]

View attachment 4218349

Sorry Francois, i can't visualise what this drawing is trying tell me. can you explain please.. thanks

 

[jazzyvee]

It will take time for you to relearn the intonation of the instrument. The bridge should remain properly positioned.

Last night i decided to put the old strings back on until i fully grasp what i need to do understand and do when changing strings. Now these older strings are back on, the notes are where my evolving muscle memory expects them to be.

Please continue with your advice as the new strings felt much easier and warmer sounding so i would like to use them once i know how to make the change confidently.

 

[Francois Blais]

Sorry Francois, i can't visualise what this drawing is trying tell me. can you explain please.. thanks

This is a side view of a virtual bass.
Shows how the bridge should look like, shows which side should be toward the tailpiece.
Please take a few pics of your bridge so we can see if something is wrong.

 

[Wasnex]

Please continue with your advice as the new strings felt much easier and warmer sounding so i would like to use them once i know how to make the change confidently.

I am not sure I understand. The bridge goes in exactly the same place regardless of the strings. The feet should be flat on the face of the instrument or they will bite into the wood and damage it. So you can't tilt the bridge to change the vibrating length of the strings.

Since there is no intonation compensation on the instrument, you have to get used to the way the way it intonates with the new type of string. In other words you must compensate for the change.

There may be some other necessary changes to the setup. For example the new strings may be a larger diameter, so the slots at the nut and bridge may be the wrong size. Keep in mind, it's much easier to make the slots larger than to make them smaller. Also since the tension of the new strings is lower, you may need to adjust the length of your bridge (string height) to compensate...assuming you have bridge adjusters installed.

 

[Wasnex]

This is a side view of a virtual bass.
Shows how the bridge should look like, shows which side should be toward the tailpiece.
Please take a few pics of your bridge so we can see if something is wrong.

The image would be better if it included the front panel and fingerboard. To my eyes the image creates the perception that the bridge is tilted back massively towards the tail piece, and I have never seen a properly adjusted bridge that looked the way this image appears to me.

The angles may be correct, and the missing front panel creates sort of an optical illusion. Or perhaps the angles are exaggerated for effect...I can't tell.

Image from Gollihur's website.

 

[Francois Blais]

It was just a quick drawing I made years ago.
It was of course somewhat exaggerated, but it was meant to show the assymetry in a properly made bridge.
There's a right angle with the feet plane at its back side.

 

[DoubleMIDI]

Lower tension strings (and more than that easier stretching strings like synthetics and gut core) rise the tension less when stretched by a constant amount which happens when you press down a string. That‘s the reason why it has happened if the bridge is kept in place and perpendicular to the top.
That‘s the way it is. You will adapt after a while.

 

[jazzyvee]

It was just a quick drawing I made years ago.
It was of course somewhat exaggerated, but it was meant to show the assymetry in a properly made bridge.
There's a right angle with the feet plane at its back side.

Thanks, what was confusing me was the word Top at the bottom of the picture, so i was thinking the image was with the bass on it's back and looking down from above and the bridge being thicker where the E string goes over it and thinner where the G string goes over it. Which is not how my bridge looks. but the photo makes your point clearer to me. It's too challenging at the moment for me to compensate so i will leave well alone until i understand what i am doing.

 

[jazzyvee]

I don't have a side view of the bridge but this might help you see how it is setup.

 

[Francois Blais]

Thanks.
It seems there’s no indication as to where the bridge should rest.
On a DB, it’s the inner notches on the F-holes.
On my EUB, there’s a beveled area on the tone bars that support the bridge.

 

[DoubleMIDI]

I would check if the bridge could be a seventh of the full vibrating string length away from the middle of the pickup. That way the inharmonic (to the classical just intonation) seventh partial gets eliminated from the amplified sound. At least it would make some sense sonically.

 

[jazzyvee]

I am not sure I understand. The bridge goes in exactly the same place regardless of the strings. The feet should be flat on the face of the instrument or they will bite into the wood and damage it. So you can't tilt the bridge to change the vibrating length of the strings.

Since there is no intonation compensation on the instrument, you have to get used to the way the way it intonates with the new type of string. In other words you must compensate for the change.

There may be some other necessary changes to the setup. For example the new strings may be a larger diameter, so the slots at the nut and bridge may be the wrong size. Keep in mind, it's much easier to make the slots larger than to make them smaller. Also since the tension of the new strings is lower, you may need to adjust the length of your bridge (string height) to compensate...assuming you have bridge adjusters installed.

Maybe my description was wrong.What I meant by angle is keep the bridge flat on it's base but twist the bridge so that I can slightly alter the string length like you would do on an electric bass when adjusting the intonation.
As it happens i put the old strings back on since I had my first gig coming up and had enough to worry about without this anomaly.
Anyway that gig is done and this week I put the new strings back on the bass and marked the bridge position with tape so I could make sure it did not move. I changed the strings and the bridge has not moved.

The notes still seem to be in a different place than with the older strings and by that i mean this.
1) With the bass tuned, the position of the notes have moved towards the bridge so for example if I play low G on the E string, and compare to an open G, the fingered note is closer to the bridge than it was previously.
2) the span of two semitones is larger than it was previously .

But the upside is that the strings feel and sound much better (woodier) and less tight and easier to finger.
Understand I am still a complete novice on this and the note positions may be as much to do with my level of playing as it is to anything else so I am not ruling myself out of the issue.

But does what I am experience make any sense?
At this point, as someone kindly pointed out earlier in the thread, I will have to get down to relearning compensate for the change in intonation.

Fun fun fun.

 

[Wasnex]

Maybe my description was wrong.What I meant by angle is keep the bridge flat on it's base but twist the bridge so that I can slightly alter the string length like you would do on an electric bass when adjusting the intonation.
As it happens i put the old strings back on since I had my first gig coming up and had enough to worry about without this anomaly.
Anyway that gig is done and this week I put the new strings back on the bass and marked the bridge position with tape so I could make sure it did not move. I changed the strings and the bridge has not moved.

The notes still seem to be in a different place than with the older strings and by that i mean this.
1) With the bass tuned, the position of the notes have moved towards the bridge so for example if I play low G on the E string, and compare to an open G, the fingered note is closer to the bridge than it was previously.
2) the span of two semitones is larger than it was previously .

But the upside is that the strings feel and sound much better (woodier) and less tight and easier to finger.
Understand I am still a complete novice on this and the note positions may be as much to do with my level of playing as it is to anything else so I am not ruling myself out of the issue.

But does what I am experience make any sense?
At this point, as someone kindly pointed out earlier in the thread, I will have to get down to relearning compensate for the change in intonation.

Fun fun fun.

I am one of the few here who may angle the bridge for intonation compensation. Most will insist that the bridge should be straight across so the vibrating length of all strings is the same. On some basses I have found it necessary to slide the E-side foot down a bit. This may not totally correct the problem, but in my experience it has helped enough. I have not found it necessary to do this on every upright I have played.

I am not a luthier and moving a bridge foot out of position may pose some concerns for the structural integrity of a given bass. I have done this with several basses and never experienced any problems, other than making a new mark on the face of the instrument, and revealing the mark left by the original foot placement. I would estimate the max compensation I use to be somewhere between 1/4" to 1/2".

It's not unusual for a change in strings to modify the intonation. The more different the new strings are, the more change you should expect. Even replacing strings on bass guitar (with exactly the same gauge and model) can throw the intonation out.

I also tend to cut down the slots in the nut on most basses I have played. If the action near the nut is too high, it can definitely impact intonation when you are playing close to the nut. Also high action increases the amount of strength you must use to press notes to the fingerboard. My preference is for the tension to feel relatively even across the strings near the nut, and otherwise be as low as possible.