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jUshwa
07-28-2011, 05:10 PM
Recently I've been reading about tuning and buying new ukuleles, the thing that keeps popping up are these numbers like A +5/A 0 and I'm kind of lost on that subject.

Also, I've been wondering how I can improve my ukulele because I think my nut is too high as the 1st fret is a little hard to play and compared from open to the 12th fret it sounds just a tad bit off. Is that what the cents mean by like comparison between open and 12th?

shutinanxiety
07-28-2011, 09:12 PM
there are 100 cents in a semitone. if a string is at a B and you need it to be C, you need to tune it 100 cents higher. if a string is playing a pitch exactly in the middle of B and C it's B+50cents

jUshwa
07-28-2011, 09:27 PM
Ah all right, so cents are like the difference between each tone like the lines on tuners?

shutinanxiety
07-28-2011, 09:49 PM
exactly. if you have a tuner that show cents, play a string open, say the C string, tuner should say dead on C. (tune it if not) then when you play first fret it should say dead on C#/Db. if it's off the tuner will tell you by how many cents. try the 12th fret. it should say dead on C again. this is called intonation and is affected by multiple factors.

mm stan
07-28-2011, 10:24 PM
Each note on your tuner is broken up into individual incriments...in 10's... +50 to +10 0 -10 TO -50 zero is 440hz ....each incriment goes by 10....so -10 would be 439, -20 would be 438 and
so on... and +10 would be 441, +20 would be 442... hope it helps... 440hz is the accepted standard tuning in the US now..other countries or the past may differ..

PhilUSAFRet
07-29-2011, 12:41 AM
When my wife asks me for change, I frequenty tell her "sometimes I have cents, sometimes I have no cents at all." ;)

jUshwa
07-29-2011, 09:02 AM
So, what if there is change in the other frets even when the string is open? Borrowed my friends tuner and it's like all the way to the right when I play 12th fret C string and when it's open it's on it. That's a bad thing right?

shutinanxiety
07-29-2011, 10:08 AM
Each note on your tuner is broken up into individual incriments...in 10's... +50 to +10 0 -10 TO -50 zero is 440hz ....each incriment goes by 10....so -10 would be 439, -20 would be 438 and
so on... and +10 would be 441, +20 would be 442... hope it helps... 440hz is the accepted standard tuning in the US now..other countries or the past may differ..

to my understanding this isn't exactly correct. cents are a logarithmic function and not directly proportional to frequency. A above middle C is 440Hz. A# above middle C is roughly 466.16Hz. that a difference of 26.16 Hz or 100 cents. B above middle C is roughly 493.88Hz. that is a difference of 27.72hz or 100 cents.

the closest two semitones to being 10 Hertz apart are E3 (164.81Hz) and F3 (174.61Hz). therefore, even though each semitone is 100 cents, every semitone is not necessarily 10 Hertz. cents are logarithmic compared to Hertz and Hertz are exponential compared to cents and are in no way directly proportional to one another. this wikipedia link on the subject may be more clear. http://en.wikipedia.org/wiki/Cent_%28music%29

also, just to clarify, zero is only 440Hz when playing the first A above Middle C (A string). C string is tuned to Middle C which is roughly 261.63Hz

shutinanxiety
07-29-2011, 10:47 AM
So, what if there is change in the other frets even when the string is open? Borrowed my friends tuner and it's like all the way to the right when I play 12th fret C string and when it's open it's on it. That's a bad thing right?

I'm no luthier but as an engineering student i can shed "SOME" scientific light on the matter. as i said before, intonation is dependent on many factors. it works like this. the pitch a string produces depends on a set of variables. the tension the string is under, the length of the string, and the diameter of the string. the diameter was chosen when you bought your strings, the tension was set when you turned the tuning pegs, and the length of the string is changed when you press the string against a fret. if you're A string tuned to 440Hz the twelfth fret (exact middle of the string) should produce a pitch of 880Hz (octaves are exactly double or half the frequency).

you'll notice that the frets get closer together as they go up the fretboard. each sequential fret is roughly 6% closer than the previous fret. (this reinforces what i said earlier about each semitone not being a difference of 10 Hertz. in the range that most humans can hear the difference in Hertz increases by "ROUGHLY" 6%)hopefully whoever made your Uke took care in spacing your frets properly. also you'll notice your strings are not perfectly parallel to your fret board. they're set at a very acute angle probably less than 1 degree. this means your strings, fretboard and saddle form a very thin triangle. the string is the hypotenuse and the fretboard is the adjacent side and the saddle is the opposite side from the angle formed at the nut (the angle is actually past the nut probably somewhere over the headstock or even farther).

so in simplest terms, sanding or shaving or filing the saddle decreases this angle making the over all length of the string less than what it was before you shaved the saddle. lowering the string height at the nut makes the string longer. (lowering the strings too much can cause the strings to touch more than one fret at a time when your press a string causing buzz or even dead frets). changing the string lengths changes the midpoints. you want the mid point to hit were the 12th fret is.

but there is even more trouble. when you press the string down at the 12th fret the string stretches and now your triangle is formed at the 12th fret making the angle much larger and increasing the tension in the string. you can see that the string and fretboard make a much sharper angle at the first fret than the do at the 12th fret because the opposite side (saddle) stayed the same but the adjacent side (fretboard) is much shorter.

and there are definitely many more factors at play here than i have mentioned, where the ridge of the fret is for instance. again, i am not a luthier by any definition and you will probably find the most help on the luthier's board. but if your uke is cheap it may cost more to have a professional fix it than what it is worth. but if it is cheap you won't be out too much if you mess it up trying to fix it yourself!

jUshwa
07-29-2011, 06:19 PM
Wow, another thing about music I now acquire haha thanks shutinanxiety I have a better understanding of it now. But since I made my own ukulele and it was my first one without paying too much attention to those factors i.e. the importance of the nut and saddle compared to tone which my instructor did not tell me -__- I think I should fix the nut as I am always having problems with it because of both buzz and the constant unsteady tone quality I get. Sometimes it's in tune other days it isn't, it may or may not be the cause but the strings are not the problems as I have stretched it for over a month and shouldn't be giving problems now hopefully. Now I'm starting to wonder if I could tweak the nut to improve the quality of my uke :/

shutinanxiety
07-29-2011, 06:38 PM
ah i see. that's really cool. i'd say if you're 12th fret is only 50cents sharps of being a perfect octave, that's pretty close and not bad for a first build. i'll have to try my hand at it some day! you should for sure ask in the luthier's board. i'm sure someone there can tell you exactly how to fix the strings being progressively sharp. i guess the good news is, if you lower the nut or saddle too much you can just replace them without scrapping the whole uke and try again.

jUshwa
07-30-2011, 08:06 PM
Thanks haha, took the longest time cause it was my first one, messed up quite a bit to be honest but okay, I'll try out the luthier board to see if I can adjust it, how and if I should just have a pro do it. Thanks so much :D