Loss of bass lowering the saddle?

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jorge rodriguez
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Loss of bass lowering the saddle?

Post by jorge rodriguez »

Hi all,

I recently purchased a used Blueridge Br160 on Ebay. I don't like buying guitars without trying them first, but it was a good deal and these guitars are not easy to find here in Spain.
It was in good state when I received it, but the strings where too high, and even more with medium strings as I normally use. So I lowered the saddle to a reasonable action. The saddle is now between 3/32'' and 7/64'', and the strings are about 0,430'' from the top in front of the bridge. I know this is not ideal, but I would think it's within reasonable measures.
I have noticed, though, that the guitar lacks some bass to my ear. Maybe I am used to playing other guitars that have more bass, but it sounds a bit thin to me, and this guitar (forward shifted scalloped bracing, solid rosewood back and sides, solid sitka top) should have plenty of it.
Is it possible that lowering the saddle has caused the loss of bass? It's hard to tell if the modification is the cause, as the strings were so high at the beginning that I could barely play it, so maybe this is how it sounded from the start.
Is a neck reset recommended in this case? Would it help get achieve a bassier sound? Any other recommendations to enhance the sound in this direction? Maybe change to an ebony bridge? (just thinking...)
I do guitar repairs and I have done neck resets in the past, so money is not a problem, I just don't want to take the trouble unless it's necesssary.
I would appreciate any recommendations.

Thanks!

Bob Orr
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Re: Loss of bass lowering the saddle?

Post by Bob Orr »

A picture of the bridge would help. Could be lowering the bridge saddle has reduced the break angle of the base strings too much which could affect the volume of the base strings.

Marshall Dixon
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Re: Loss of bass lowering the saddle?

Post by Marshall Dixon »

jorge rodriguez wrote:
Thu Mar 05, 2020 10:35 am
Hi all,

The saddle is now between 3/32'' and 7/64'', and the strings are about 0,430'' from the top in front of the bridge. I know this is not ideal, but I would think it's within reasonable measures.

I do guitar repairs and I have done neck resets in the past, so money is not a problem, I just don't want to take the trouble unless it's necesssary.
I would appreciate any recommendations.

Thanks!
Hello Jorge,

What is the action at the 12th fret? How much saddle is protruding above the bridge? It sounds like saddle height above the soundboard is on the high side at .043 inches and a neck reset would be done if that measurement were too low. No?

I have found, and would expect, a noticeable change in tone with a reduction of saddle height over 10%. Maybe even less depending on the guitar. Everything about the bridge; the depth of the saddle slot, the amount of saddle above the slot, the saddle material, the break angle, the bridge plate material, weight and stiffness and the overall height of the saddle are primary to the sound.

I think the first thing to try is a different set of strings or two before any surgery.

You can purchase metal bridge plate reinforcements pieces to help where ball ends have dug into the bridge plate. This may alter the tone to your liking... or not. But would be a cheap, easy fix if it worked.

I have found that reducing the stiffness of the bridge wings increased bass response and treble response with it. I can't give any mathematical recommendations as this is something I intuit along with the flexibility of the top. Before replacing the bridge I'd sculpt it for sonic response.

I think the bridge can be easily overlooked in the importance it plays to the sound.

jorge rodriguez
Posts: 56
Joined: Tue Jun 12, 2012 7:38 pm

Re: Loss of bass lowering the saddle?

Post by jorge rodriguez »

Thanks for your replies.

I will upload a picture later, but I think the break angle looks ok.

There is between 3/32'' and 7/64'' saddle protruding above the bridge. The action at the 12th fret is now about 0,095'' at the low E, and about 0,085'' at the high e.

jorge rodriguez
Posts: 56
Joined: Tue Jun 12, 2012 7:38 pm

Re: Loss of bass lowering the saddle?

Post by jorge rodriguez »

Here's some pics:

https://ibb.co/hHMQps5
https://ibb.co/0yppxRz

Thanks again!

Alan Carruth
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Re: Loss of bass lowering the saddle?

Post by Alan Carruth »

Lowering the string height off the top reduces the input from the string tension change, which enhances the 2nd and 4th partials a bit. It won't cut the fundamental directly, but even partials can add 'fullness' to the sound, which can come across as 'bassier'. Lowering the action also limits how hard you can play before you get fret buzz, of course.

Marshall Dixon
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Location: SW Oregon

Re: Loss of bass lowering the saddle?

Post by Marshall Dixon »

jorge rodriguez wrote:
Thu Mar 05, 2020 12:00 pm
Thanks for your replies.

I will upload a picture later, but I think the break angle looks ok.

There is between 3/32'' and 7/64'' saddle protruding above the bridge. The action at the 12th fret is now about 0,095'' at the low E, and about 0,085'' at the high e.
Those numbers look good. But there is something strange in that you received it with so high an action. Is the neck stable? Any problems with the neck joint? Have you looked inside for any offending mass? I once forgot a bridge caul inside stuck in with double sided tape. That will effect the tone!

You mentioned replacing the bridge, so you sound adventurous. Looking at the pictures it’s hard to tell the thickness of the bridge wings. There appears to be a good bit of material that could be shaved away in the pin section (rear) of the bridge. How much to remove from the front would be determined by the depth of the saddle slot (equal to or more than the height of the saddle over bridge). Thinning the wings especially nearest the middle section will have a great effect. I go for a 10% reduction in height at a time. I use playing cards as a guide and tape as many down in front of and behind the bridge to the height needed. Make the cuts with a razor saw. You can do this with the guitar strung up and get immediate feedback. If you’re going to replace the bridge anyway this is a great learning opportunity.

ps - I didn't see any mention of saddle material but if it’s plastic the very first thing I'd do is replace it with bone.

jorge rodriguez
Posts: 56
Joined: Tue Jun 12, 2012 7:38 pm

Re: Loss of bass lowering the saddle?

Post by jorge rodriguez »

Marshall Dixon wrote:
Thu Mar 05, 2020 4:12 pm

Those numbers look good. But there is something strange in that you received it with so high an action. Is the neck stable? Any problems with the neck joint? Have you looked inside for any offending mass? I once forgot a bridge caul inside stuck in with double sided tape. That will effect the tone!

You mentioned replacing the bridge, so you sound adventurous. Looking at the pictures it’s hard to tell the thickness of the bridge wings. There appears to be a good bit of material that could be shaved away in the pin section (rear) of the bridge. How much to remove from the front would be determined by the depth of the saddle slot (equal to or more than the height of the saddle over bridge). Thinning the wings especially nearest the middle section will have a great effect. I go for a 10% reduction in height at a time. I use playing cards as a guide and tape as many down in front of and behind the bridge to the height needed. Make the cuts with a razor saw. You can do this with the guitar strung up and get immediate feedback. If you’re going to replace the bridge anyway this is a great learning opportunity.

ps - I didn't see any mention of saddle material but if it’s plastic the very first thing I'd do is replace it with bone.
I checked inside and everything looks good to me... no unglued braces, no strange stuff. The only thing I noticed is a structure below the fretboard extension, like a mahogany block, it's made to contain the truss rod that goes up to the soundhole. But if I'm not mistaken other brands have similar constructions and it should not be a problem.... I might be mistaken.

I don't consider myself a luthier, but I have done some building and repair and learnt a bit from a couple of luthiers, so I am not scared of trying repairs. I would think twice if it was a vintage Martin :)

Not sure if I understand correctly, but are you suggesting I could remove material from the front and back of the bridge?

About the wings, they are 0,115'' thick at the end... not sure if this could be lowered?

Also, not so sure of what you mean by "make the cuts with a razor saw". I would assume that sanding would be the easiest way of thinning down the wings?

Oh and yes, the saddle is bone.

Thanks!

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Barry Daniels
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Re: Loss of bass lowering the saddle?

Post by Barry Daniels »

I don't see much room for improvement here. It definitely doesn't need a neck reset. The guitar is probably just over-braced, like many factory guitars, so there may be no magic bullet.
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Marshall Dixon
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Re: Loss of bass lowering the saddle?

Post by Marshall Dixon »

jorge rodriguez wrote:
Thu Mar 05, 2020 4:39 pm

Not sure if I understand correctly, but are you suggesting I could remove material from the front and back of the bridge?

About the wings, they are 0,115'' thick at the end... not sure if this could be lowered?

Also, not so sure of what you mean by "make the cuts with a razor saw". I would assume that sanding would be the easiest way of thinning down the wings?

Oh and yes, the saddle is bone.

Thanks!
The bridge is a large brace. It moves back and forth, up and down and in a twisting motion also. Besides the weight and overall dimensions, the stiffness has a large part to play in that movement. You'll make the greatest change here by lowering the thickness as close to the center as possible, but the structure of the center needs to be adequate for the stresses so you can't change too much there. But it looks like you have a lot of wood lateral to the ends of the saddle to play with.

How the guitar is braced and the thickness of the bridge patch and it's mass all make a difference. I've thinned the bridge patch and noticed a change.

I would measure the thickness close to the middle section. It looks like it slopes from the mid section to the end and is fairly thick in the middle. You're going to have to change the curvature of the bridge near the middle to conform to the new depth. This is where your inner artist shines. Once you make the cut the stiffness changes. You can pretty things up after several cuts assessing the change in sound after each. The strength of a beam in relation to It's height is roughly a 10% change in height is about 30% change in stiffness. You should hear something different but weather it will be to your liking is another matter.

When I said razor saw I meant something with a thin blade and 60 teeth per inch. I use a Gyros brand. But also use a file and sanding block and scraper. Whatever it takes. Protect the top.

jorge rodriguez
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Re: Loss of bass lowering the saddle?

Post by jorge rodriguez »

Thanks Marshall. I think I understand what you mean. I will give it a think before I jump on it with my saw, but it sounds doable. :)

Marshall Dixon
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Location: SW Oregon

Re: Loss of bass lowering the saddle?

Post by Marshall Dixon »

jorge rodriguez wrote:
Fri Mar 06, 2020 4:27 am
Thanks Marshall. I think I understand what you mean. I will give it a think before I jump on it with my saw, but it sounds doable. :)
Take a look at “guitar bridge images” online. Definitely think on it. Play it for half a year. I've experimented with half dozen or so bridges this way. I have purposely built with oversized braces just so I could hear what happens when they are lowered. The problem is that you don't know how far is too far until it's too late. But that is the reference for next time.

Here is some interesting reading about guitar acoustics: http://www.speech.kth.se/music/acviguit4/part1.pdf

jorge rodriguez
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Joined: Tue Jun 12, 2012 7:38 pm

Re: Loss of bass lowering the saddle?

Post by jorge rodriguez »

Marshall Dixon wrote:
Fri Mar 06, 2020 11:14 am

Take a look at “guitar bridge images” online. Definitely think on it. Play it for half a year. I've experimented with half dozen or so bridges this way. I have purposely built with oversized braces just so I could hear what happens when they are lowered. The problem is that you don't know how far is too far until it's too late. But that is the reference for next time.

Here is some interesting reading about guitar acoustics: http://www.speech.kth.se/music/acviguit4/part1.pdf
Thanks! It is a very complex matter and I have a lot to learn and not as much time as I would like to. Appreciate the document, I will read it!

Alan Carruth
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Re: Loss of bass lowering the saddle?

Post by Alan Carruth »

If the problem is just a general lack of bass response it could be over built, as has been said. Sometimes the best way to address that is to shave back braces,to lower the 'main back' tap tone more in line with the pitch of the top. This can be surprisingly effective and doesn't compromise the strength or stiffness of the top, as can happen when you shave top braces. As always, the 'proper' solution depends on just what's wrong, and we may not be able to diagnose that on line.

jorge rodriguez
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Re: Loss of bass lowering the saddle?

Post by jorge rodriguez »

Alan Carruth wrote:
Fri Mar 06, 2020 12:21 pm
If the problem is just a general lack of bass response it could be over built, as has been said. Sometimes the best way to address that is to shave back braces,to lower the 'main back' tap tone more in line with the pitch of the top. This can be surprisingly effective and doesn't compromise the strength or stiffness of the top, as can happen when you shave top braces. As always, the 'proper' solution depends on just what's wrong, and we may not be able to diagnose that on line.
Interesting, thanks!

jorge rodriguez
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Joined: Tue Jun 12, 2012 7:38 pm

Re: Loss of bass lowering the saddle?

Post by jorge rodriguez »

Thanks to this thread I found another issue in the guitar :) Two of the back braces have a small section where they are unglued.
The comment about the back bracing made me start tapping the back and I found a rattle. Inspecting the braces I found the problem.

Here's a pic of my dry run for the repair:

IMG_20200310_122717.jpg

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Barry Daniels
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Re: Loss of bass lowering the saddle?

Post by Barry Daniels »

You might want to also apply a clamp on the outside of the guitar to resist the pressure from the internal clamps. This will also help to press the back down and close the gap.
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jorge rodriguez
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Re: Loss of bass lowering the saddle?

Post by jorge rodriguez »

Thanks Barry! Will try that.

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Bryan Bear
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Re: Loss of bass lowering the saddle?

Post by Bryan Bear »

Barry took the words out of my mouth. Make sure you protect the surface of the top from the clamp so you don't mar or dent it.
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Take care of your feet and your feet will take care of you.

jorge rodriguez
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Re: Loss of bass lowering the saddle?

Post by jorge rodriguez »

Thanks so much for the tip... I was just doing the repair now and clamping outside was exactly what allowed the gap to close :)

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