Re: Phiew.... guitar intonation - hard work!

[Douglas Baldwin <coyotelk@optonline.net>]

For what it's worth, here's how I wrapped my head around string 
construction 
and intonation, and perhaps why Per is having trouble with his axe...

If a string could be reduced to a Platonic ideal, it might have zero mass, 
and the 12th fret would be exactly beneath the half-way point between the 
nut and the bridge. But this ain't the case and, given a set scale length 
and a generally set range of string tension, the strings have to have 
greater mass to achieve lower pitches. The greater the mass, the greater 
the 
string's pitch changes to a given amount of added tension. That's why, on 
a 
standard guitar, if you give a half-turn down to the tuning gear of the 
plain .010 high E string, it will drop to a slightly sharp D# (less than a 
half step), while if you do the same to the plain .017 G string, it will 
drop to a flat F natural (over a whole step). Whenever you press the 
string 
down, you're adding a bit of tension to the string, and in order to 
compensate for this slight pulling-the-string-sharp effect, the string 
length is made a little longer at the bridge saddle. The difference 
between 
the string masses can be seen at the bridge saddles, where the saddle of 
the 
plain .010 high E will be just a smidgen past the Platonic Ideal of 
twice-the-12th-fret length, but the saddle of the fatter plain .017 G 
string 
will be two or three more smidgens longer.
    The wack part of this observation is what happens when you deal with 
wound strings, because the windings add to the pitch-lowering mass of the 
string WITHOUT adding to (or subtracting from) the tension necessary to 
reach their desired pitch. Think of it like this: the windings are like a 
Slinky wrapped around a clothesline. If you pluck the clothesline, it will 
move slower than if it didn't have the Slinky wrapped around it, but it 
won't have any extra tension on it. On the guitar, this means that the 
intonation points for the wound strings are more like the intonation 
points 
for the core wire than for the actual diameter of the string. The 
intonation 
point of a wound .026 D string will be closer to the intonation point of 
its 
core wire, which is probably .014, and NOT the expected many-many smidgens 
of a solid plain .026 string. This explains the typical three-steps 
down-then-three-steps-down-again pattern of a properly intonated bridge 
saddle on a standard-tuned guitar.
    The more you deviate from standard tuning on a standard-designed 
guitar, 
the more you need to either change string gauges or accept the problems of 
pitch. On my new-standard-tuned Guitar Craft Ovation guitar (tuned 
C-G-D-A-e-g, low to high) I use an .070 for the low C. It is strong and 
firm 
and equal in response to the other strings, and intonatable within the 
range 
of the Ovation saddle. Most others of the Guitar Craft cult don't even 
begin 
to consider this kind of string-swapping, and for years I have felt like 
the 
only sane one in the asylum for using the strings I do. But that's another 
story.
    Per, could you describe your fretted drop-B guitar a little more? The 
tuning, the guitar type, etc. Maybe I can recommend some string options to 
try...?
Best,

Douglas Baldwin
Alpha Coyote
coyotelk@optonline.net
www.TheCoyote.org

"The purpose of music is to sober and quiet the mind, thus rendering it 
suseptible to divine influences."
-- Thomas Mace (17th century), transmitted to Gita Sarabhai, as told to 
John 
Cage





----- Original Message ----- 
From: "van Sinn" <vansinn@post.cybercity.dk>
To: <Loopers-Delight@loopers-delight.com>
Sent: Thursday, April 16, 2009 7:08 PM
Subject: Re: Phiew.... guitar intonation - hard work!


> Per Boysen wrote:
>> I had my daily share of frustration today when fine tuning the string
>> length intonation on my fretted drop-B guitar. With the thicker
>> strings it seems the stings need to be just a little bit longer. Five
>> strings are good now, but for the G string (or D as this instrument is
>> tuned) the mounting of the stratocaster style bridge/tailpiece/whammy
>> does not allow the sting length needed for correct intonation. What a
>> disaster! I need to look for a smaller string slider block (or
>> whatever you call them...) to get the extra need millimeter string
>> length. Boy, do I enjoy the sweet relief of plugging in my fretless
>> for while after two hours of desperate intonation work!
>>
>> Is this "a known fact" that thicker strings need to be longer? The
>> action and string pull is the same as before - but the intonation is
>> just a different universe compare to the previous normal tuning.
>>
>> Greetings from Sweden
>>
>> Per Boysen
>> www.boysen.se
>> www.perboysen.com
>
>
> Oh yeah, just search for intonation on sevenstring.org ;)
> This is why many opt for 27" and beyond when downtuning: Longer scale 
> means more tension, so thinner strings can be used, resulting in better 
> intonation and a crisper tone with more piano-like attack.
>
> It gets even more interesting with 8-stringers and beyond :D
> Then the problem with too thin upper strings pops up.
> The natural cure is to use multi/compound scale AKA fanned frets, which 
>of 
> course doesn't help anything on your Strat..
>
> -- 
> rgds,
> van Sinn
>