Double Bass Intonation Problems on one string of an upright bass

C

Colin Kyger

Jan 12, 2020
10
2
2,586
#1
Recently started renting an upright bass from a local music shop, I noticed that the G string is a bit off compared to the other three strings. This might be a bit tricky to explain so bear with me, when all the open strings are in tune using a tuner and I'm using the proper right hand technique on my upright the E, A, and D string are fine but when I'm using the proper hand technique on the G string and I'll go to play a C or anything passed it I have to move my right hand a 16th to an 8th of an inch down to keep it in tune because if I don't then I'll be sharp.

In other words my G string is not in tune with the rest of my bass despite all the open strings being tuned almost perfectly to a tuner and my question is what is causing the problem and how can I fix it?
 
#2
Colin Kyger said:
Recently started renting an upright bass from a local music shop, I noticed that the G string is a bit off compared to the other three strings. This might be a bit tricky to explain so bear with me, when all the open strings are in tune using a tuner and I'm using the proper right hand technique on my upright the E, A, and D string are fine but when I'm using the proper hand technique on the G string and I'll go to play a C or anything passed it I have to move my right hand a 16th to an 8th of an inch down to keep it in tune because if I don't then I'll be sharp.

In other words my G string is not in tune with the rest of my bass despite all the open strings being tuned almost perfectly to a tuner and my question is what is causing the problem and how can I fix it?
Click to expand...
Sounds like the bridge is crooked, with the G string side either too far in the end pin direction or too far towards the nut (depending on what you mean by “down”). How about posting some pictures of the position of your bridge so that we can see its position?
 
  • Like
Reactions: RSBBass and unbrokenchain
#3
Colin Kyger said:
Recently started renting an upright bass from a local music shop, I noticed that the G string is a bit off compared to the other three strings. This might be a bit tricky to explain so bear with me, when all the open strings are in tune using a tuner and I'm using the proper right hand technique on my upright the E, A, and D string are fine but when I'm using the proper hand technique on the G string and I'll go to play a C or anything passed it I have to move my right hand a 16th to an 8th of an inch down to keep it in tune because if I don't then I'll be sharp.

In other words my G string is not in tune with the rest of my bass despite all the open strings being tuned almost perfectly to a tuner and my question is what is causing the problem and how can I fix it?
Click to expand...

Are all 4 strings the same type? The type and gauge of the string has an impact on intonation.

In doing a Google search, it appears that the dominant idea is the bridge is not compensated on double bass. I am a bit surprised as most people I have discussed this with angle the bridge slightly so the vibrating length of the E string is a bit longer than the G string. Right or wrong, this is how I setup my basses, and I feel it helps make intonation across the strings more consistent. :bag:
 
#4
It's also possible the G string is bad.

Or, it could be the height of the strings above the neck is not set properly. I.E. if the G string is too high or too low the intonation will suffer. This could be something as simple as the bridge was bumped so the strings are no longer centered properly over the fingerboard.

The radius of the fingerboard and bridge should be pretty much the same, but I would expect the strings to get progressively higher as you move from G to E. However, the difference in height is subtle.
 
#7
statsc said:
Sounds like the bridge is crooked, with the G string side either too far in the end pin direction or too far towards the nut (depending on what you mean by “down”). How about posting some pictures of the position of your bridge so that we can see its position?
Click to expand...
20200112_140657.jpg
20200112_140652.jpg
20200112_140702.jpg
 
  • Like
Reactions: Wasnex
#9
Colin Kyger said:
View attachment 3665155 View attachment 3665156 View attachment 3665157
Click to expand...
Yup; as I suspected! The E string side of the bridge should be moved a bit towards the nut and the G string side of the bridge moved a bit towards the end pin. An imaginary line drawn connecting the inside f-hole notch on the E string side to the inside f-hole notch on the G string side should pretty much pass through the middle of each bridge foot. Also, the end pin side of the bridge should be approximately perpendicular to the top of the bass.

I think a trip to a real bass luthier for a professional set-up would be in order, since it appears that the music store you rented this from doesn’t really know how to set up an upright bass if this was the condition you got it in.
 
  • Like
Reactions: Chris Fitzgerald, Povl Carstensen, Scott Lynch and 1 other person
#10
Wasnex said:
Are all 4 strings the same type? The type and gauge of the string has an impact on intonation.

In doing a Google search, it appears that the dominant idea is the bridge is not compensated on double bass. I am a bit surprised as most people I have discussed this with angle the bridge slightly so the vibrating length of the E string is a bit longer than the G string. Right or wrong, this is how I setup my basses, and I feel it helps make intonation across the strings more consistent. :bag:
Click to expand...
I have never heard of angling the bridge as you describe from any luthier or bass player.
 
  • Like
Reactions: GypsyBilly, the_Ryan, BobKay and 2 others
#13
statsc said:
I have never heard of angling the bridge as you describe from any luthier or bass player.
Click to expand...

As I mentioned, having the bridge straight comes as a surprise to me, thus why I put :bag: with my comment. From what I have seen, there tends to be regional differences in technique and setup among UB players. I.E. a master in an area may have an influence on the players in an orchestra for example. I believe this is something I was taught in my hometown from the principal bassist of the local symphony, and an adjustment that I do as necessary on the basses I play. However, if the intonation is fine without the compensation, I leave the bridge alone.

I think the angle of the OP's bridge looks extreme, and it is likely the source of the problem. I could also be an attempt to correct the problem :facepalm:; so maybe there are other issues with the bass.
 
  • Like
Reactions: GypsyBilly and AGCurry
#15
JeffKissell said:
It will be much easier to play and intonate when it's set up properly.
Click to expand...
x1,000...

How about a shot of the nut on this bass? There's a chance it could have been setup properly at some point and then had the bridge knocked over and set back reversed and crooked, possibly even by another renter? But also could have just never been setup right in the first place..
 
  • Like
Reactions: GypsyBilly
#19
The slots in the bridge don't look right. Notice that the G string notch is the same size as the E string notch. Also, the notches in the bridge are square, they should be round and approximately the same width as the string they hold. Somebody messed with the bridge, take it back to where you rented it and have them fix it, or let them send it out to be made right
 
  • Like
Reactions: GypsyBilly and gnypp45
You must log in or register to reply here.
Top Bottom
Back