Jump to content

Intonation Minutae


Wonko

Recommended Posts

New guy here. If this topic has been done to death, please just refer me to the correct part of the archives. I looked, but didn't find it.

Does anyone here know mos' everything about intonation? I've got two issues where it will be critical for me soon.

1. Cheap acoustic Washburn bass (4-string with frets). I want to change to BEAD strings (flatwound), but getting the B string will be so hard (must be33.5" - 34.5" long at the thick part) and costs a bit, so I want to know the answer if possible beforehand.

The acoustic has no intonation adjustments. It does have a typical angled bridge to sort of put you in the zone, but it's always off some. Question (a): do flatwound strings require more intonation offset than roundwounds, in general? By "offset", I mean the difference between the adjusted string length and twice the distance between the nut and the 12th fret. If there's a regular term for this, I'd love to know it. Question (B): do fatter sting sets require more offset than skinnier strings?

2. I'll be building a strat-style 4-string bass soon, and I'd like to put the bridge in exactly the right place (unlike my current 5-string, which has it about 2mm too close to the nut). Is there a way of predicting what your intonation range is going to be for a particular type/size of strings, so that you can set the bridge in the best place?

Link to comment
Share on other sites

I dunno about question 1, but 2 is an easy one. Here is what I did on my bass:

1. Set the saddles to the middle of the adjustment range.

2. Determine what the the scale length is (if you are buying a neck, you must use the scale of the neck, however if you are making your own neck, you can make it to whatever scale you wish).

3. Once the neck is in place, either by gluing, bolting, etc, measure, from the nut, the scale length of the neck. I.E., if you are building a 34" scale bass, measure down the center of the neck 34" and mark the body at that point.

4. Line up the bridge with the marking you just made.

Since your saddles are in their center position, this will give you room to both shorten and lengthen the string to set intonation.

Hope that helps. If I hadn't just woken up, I'm sure I could have given better instructions.

Link to comment
Share on other sites

Crud. I think I messed up. Meant to put a reasonable reply in here. I'll try to edit:

Thanks. I'm aware of that method, which usually works, but in some cases, the need for intonation adjustment overcomes the bridge's ability to adjust it. As in my case.

Since some strings require (a lot) more adjustment length than others, and since some types of strings require (generally) longer adjustments than others, getting the right place isn't quite that easy. Moving the bridge a mm or two longer or shorter makes sense to me if I'm building a guitar for a certain type of string. Flatwounds, in this case. So, regarding this fine adjustment, the question remains untouched.

We all know that fatter strings have to be intoned longer than skinnier strings. Are flatwounds adjusted longer than roundwounds? Or are they more diverse in adjustment than roundwounds? How about nylon tapewounds?

That's the kind of info I crave.

Edited by Wonko
Link to comment
Share on other sites

Crud. I think I messed up. Meant to put a reasonable reply in here. I'll try to edit:

Thanks. I'm aware of that method, which usually works, but in some cases, the need for intonation adjustment overcomes the bridge's ability to adjust it. As in my case.

Since some strings require (a lot) more adjustment length than others, and since some types of strings require (generally) longer adjustments than others, getting the right place isn't quite that easy. Moving the bridge a mm or two longer or shorter makes sense to me if I'm building a guitar for a certain type of string. Flatwounds, in this case. So, regarding this fine adjustment, the question remains untouched.

We all know that fatter strings have to be intoned longer than skinnier strings. Are flatwounds adjusted longer than roundwounds? Or are they more diverse in adjustment than roundwounds? How about nylon tapewounds?

That's the kind of info I crave.

The answer to your question is not that cut and dried (seems like you have an understanding of how intonation works so this should be pretty obvious to you). It is true intonation is going to vary with the mass of the string and vibrating string length. The "dead" string length (bridge or nut to point the string is pinned) will also effect your intonation (and this varies from guitar to guitar). You also have to account for stretch when fretted (varies with action). We started to do a little project to determine if break angle played into intonation, but never came to a firm conclusion. I would suspect a slight difference in the intonated length for round vs flat wound (slight).

To set aside the magic numbers for a moment. You could run a test on a guitar with whatever types of strings you would prefer, and take measurements (that will give you that answer- as long as you perform the test correctly and can make VERY fine measurements). As far as placement of a new bridge... You could place a bridge use a tool like Stew Macs adjustable intonation tool( I think it is called "the Intonator") and mark the proper locations install the saddle and place it. You do have the ability to make some adjustment on an acoustic bridge saddle. You simply shape the saddle so that the string breaks more forward or to the rear. You can make split saddle bridges that give you a better angle than a one piece saddle, and as far as that goes you could place an individual saddle for each if you prefer.

As far as converting that acoustic bass and adding a low B. You may very well do damage or distort the soundboard fairly quickly by adding that extra tension. The box on an guitar sized acoustic bass is not large enough to respond to the lower frequency anyway. I would use caution so you don't destroy your toy :D .

So there is a responce. I don't think it is quite what you "crave". I hope it is helpful in some ways.

Peace,Rich

Link to comment
Share on other sites

Thank you very much. It seems like you know most of what I was looking for. Good point on the top maybe not being able to respond the the very low frequencies involved.

What extra tension? Each string, tuned to it's designed note, should have (roughly) the same tension as its fellows, shouldn't it? I'm new to the bass world, but I know that on my guitars that that has always been the idea for any balanced string set (ingeneral). That's how we avoid warped necks ~ right?

Then again, I allow that you may know something I don't.... Educate me some more, please.

Edited by Wonko
Link to comment
Share on other sites

Thank you very much. It seems like you know most of what I was looking for. Good point on the top maybe not being able to respond the the very low frequencies involved.

What extra tension? Each string, tuned to it's designed note, should have (roughly) the same tension as its fellows, shouldn't it? I'm new to the bass world, but I know that on my guitars that that has always been the idea for any balanced string set (ingeneral). That's how we avoid warped necks ~ right?

Then again, I allow that you may know something I don't.... Educate me some more, please.

My bad, I was thinking 5 string when I saw the low B. I have an issue with reading but not comprehending :D . Have fun with the projects :D .

Peace,Rich

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...