1. Please take 30 seconds to register your free account to remove most ads, post topics, make friends, earn reward points at our store, and more!  
    TalkBass.com has been uniting the low end since 1998.  Join us! :)

Intonation/Tuning Question

Discussion in 'Technique [BG]' started by Pentatonic, Feb 22, 2014.

  1. After seeing the thread on http://www.talkbass.com/forum/f21/tuning-using-harmonics-1056824/ I wanted to ask the following question.

    Can someone please explain why intonation will vary sharp or flat up and down a fretboard assuming intonation is set correctly at the 12th fret? Are the frets in the wrong places? Neck twisted? Something else?

    I ask because I recently bought a Turbotuner to do my own setups. It has been going well overall on my three basses. On my MIM Precision, according to the tuner, the intonation is spot on or very close to spot on, up and down the fretboard on each string.

    On my Squier Jazz, according to the tuner, the intonation is all over the place, some frets are sharp, some are flat, up and down the fretboard on each string. Not by much, mind you (sounds in tune), but it is clearly not as consistent as the MIM Precision. Is this a possible neck or fret issue, example of a poor quality instrument or are my expectations simply too high?

    Thanks in advance.
  2. bswag

    bswag Guest

    Dec 21, 2013
    Well... Having perused that thread, and having recently read the WikiP. entries on intonations and tempered tunings, and having played fretted things for many decades before going fretless, I'll blindly guestimate-

    First, how accurate is that Turbotuner? Your ears can usually hear better than tuners, in fact, a recent article in the Science section of The Atlantic notes how researchers have found that human hearing is vastly superior to that which would be required for speech and language alone; further, that jazz musicians jamming while in the MRI show brain activity in the areas used by language syntax, but not those used by semantics. The patterns matter more than the meaning! Our ears contain finely calibrated frequency-meters (unless we've blown them out of spec with our loud music or industrial racket), which can bedevil us if we rely on tuners to "hear" for us, and then find the results unpleasing.

    Further, Buzz Feiten determined that the ratios every fretted-instrument maker has been using for centuries virtually ensure certain (un-intended) out-of-tunenesses, eg, at the first fret of most anything (try it and see). He and his research partner have patented a system to correct all that, which some makers have adopted.

    But I'd guess the differences between your basses is mostly a matter of manufacture. I had a pair of Squier Jazzes (a fretless and a '70's fretted) which seemed OK, but then I never checked them the way you're doing! And assuming that your setup is otherwise good as far as relief and action and whatnot; pickups realreal close to strings can also be a problem, since their pull can mess with pitch.
    Alas, "sounds in tune" can be so subjective, even to ourselves; likewise, "poor quality" is a bit relative vis-a-vis price and other factors.

    Take care of those ears!
  3. Thanks for the reply.

    My ear for pitch is ok, but not great -- an electronic tuner is a godsend to me.

    I recall years ago (before common use of electronic tuners) someone coming up to me at a gig and saying after a set, " Your E string is slightly flat." He was right. :(

    Anyone else have thoughts about inconsistencies of pitch up and down the neck of a fretted instrument?

    Thank you.
  4. davidhilton

    davidhilton Supporting Member Commercial User

    Apr 13, 2009
    Los Angeles, CA
    Yeah man ur expectations r way too high...Dude- its a squire...I play an Exotic XJ-1T and its not perfect perfect perfect...
    Try not getting too far into the mechanics of playing the bass...Music is an art not a science...it probably sounds just fine.
  5. FWIW, it makes sense to rule out neck and fret problems. I'm not comfortable adjusting the neck myself so I take my instruments to a professional at GC or wherever I bought them.
  6. P Town

    P Town

    Dec 7, 2011
    bswag. Maybe you have the ability to discern a difference in pitch at a higher resolution than your basic clip-on, or pedal tuner, but I'm not sure I can. I do test myself, by tuning by ear, and then checking the tuner some times, and I do pretty good most of the time. I have compared tuners against each other to see if they vary, and I have found that they are consistent.

    The difference in frequency from one interval to the next is non-linear, so that if I can detect an error of 1.5 Hz at middle C, (I can, at times), I may not be able to discern a 1.5 Hz difference a couple octaves down, (or up?), because 1.5 Hz represents a larger, or smaller fraction of a tone, depending on the pitch.

    I would like to see how a group of people would fare tuning a bass by ear, compared to an electronic sensor. I would bet on an electronic tuner to be more accurate, more precise, and more repeatable than most human musicians.
  7. My squire affinity P bass also does this. The tuners are crap for sure. My neck is a bit bowed, action is ~.75 cm at the 12th fret (truss rod maxed). I always figured the combination caused these problems even with it properly intonated. Was given it a few years ago for free and the action was probably just under an inch when I got it!!!
  8. okcrum

    okcrum in your chest Supporting Member

    Oct 5, 2009
    Verde Valley, AZ
    RIP Dark Horse strings
    When you tune by harmonics, you are listening for the difference between the two strings, the beat. It's as easy to hear a 1.5 Hz beat at E as it is at D or G or C further up. It wouldn't be the way everyone tuned up before electronic tuners if it required aural superpowers. It works just as well on guitars, even Squiers. ;)

    In his book Serious Electric Bass, Joel Di Bartolo uses the 12th and 19th fret harmonics as a best compromise for setting intonation.

    The normal fret positions don't take into account tension or tempering, and that's why notes vary slightly sharp and flat up and down the neck. Also, the higher the harmonic, the more "out of tune" it will sound, since it follows a different mathematical relationship with the string fundamental note than that of the fret spacing.
  9. Thanks for the replies everyone.
  10. String height makes quite a big difference, as depending on where on the neck you push the string down to the frets, it stretches them - changing the string's pitch. A harmonic is just a multiple of the open tuning, fretting a note is a function of open pitch plus the fret position, plus the pull away from the note due to extra tension. Lower the action and the pitch changes are different. I suppose that frets should be in a different place for a guitar with a low action compared to a high one - but that's clearly impossible!
  11. Latitude94941

    Latitude94941 Supporting Member

    May 15, 2013
    Northern California
    Maybe YOUR ears can, but most cannot. Most of the things I've read state that humans can reliably perceive pitch differences of 5-6 cents.

    True strobe tuners are accurate to 0.1 cent.
  12. bswag

    bswag Guest

    Dec 21, 2013
    Firstly, a link to that article I mentioned (and forgot to provide, sorry!):


    As for how ears parse frequency,

    "Tonotopy in the auditory system begins at the cochlea, the small snail-like structure in the inner ear that sends information about sound to the brain. Different regions of the basilar membrane in the organ of Corti, the sound-sensitive portion of the cochlea, vibrate at different sinusoidal frequencies due to variations in thickness and width along the length of the membrane. Nerves that transmit information from different regions of the basilar membrane therefore encode frequency tonotopically. This tonotopy then projects through the vestibulocochlear nerve and associated midbrain structures to the primary auditory cortex via the auditory radiation pathway. Throughout this radiation, organization is linear with relation to placement on the organ of Corti, in accordance to the best frequency response (that is, the frequency at which that neuron is most sensitive) of each neuron. However, binaural fusion in the superior oliviary complex onward adds significant amounts of information encoded in the signal strength of each ganglion. Thus, the number of tonotopic maps varies between species and the degree of binaural synthesis and separation of sound intensities; in humans, six tonotopic maps have been identified in the primary auditory cortex.[1] their anatomical locations along the auditory cortex." (from Wikipedia)

    But frequency ain't the same as pitch:

    "Pitch is an auditory sensation in which a listener assigns musical tones to relative positions on a musical scale
    based primarily on the frequency of vibration.[6] Pitch is closely related to frequency, but the two are not equivalent. Frequency is an objective, scientific concept, whereas pitch is subjective. Sound waves themselves do not have pitch, and their oscillations can be measured to obtain a frequency. It takes a human mind to map the internal quality of pitch. Pitches are usually quantified as frequencies in cycles per second, or hertz, by comparing sounds with pure tones, which have periodic, sinusoidal waveforms. Complex and aperiodic sound waves can often be assigned a pitch by this method.[7][8][9]" (from Wikipedia)

    Then consider:

    "The just-noticeable difference (jnd) (the threshold at which a change is perceived) depends on the tone's frequency content. Below 500 Hz, the jnd is about 3 Hz for sine waves, and 1 Hz for complex tones; above 1000 Hz, the jnd for sine waves is about 0.6% (about 10 cents).[19] The jnd is typically tested by playing two tones in quick succession with the listener asked if there was a difference in their pitches.[12] The jnd becomes smaller if the two tones are played simultaneously as the listener is then able to discern beat frequencies. The total number of perceptible pitch steps in the range of human hearing is about 1,400; the total number of notes
    in the equal-tempered scale, from 16 to 16,000 Hz, is 120.[12]" (from Wikipedia)

    Got all that? Study hard, this'll be on the final. Or in other words, I think your problem bass has a more casual approach to fret placement than the good one.

    What I was trying to get at in my reply was that the intersection of tuners, our sense of pitch, and the vagaries of instrument construction, compounded by the differences between "tempered" pitches (where the frets should be) and un-tempered pitches (like harmonics), plus of course ambient racket (air conditioners, the shouts of your devoted fans), can sometimes perplex our hearing; the more so the more we think about it!

    But, to "okcrum," fret placement is very certainly supposed to be according to tempering- according to "equal temperament," in particular, for normal fretted instruments (though other systems, like "just intonation" can be used). Yes, as Mr. Feiten et al detail, it's tension- actually, end-tension- which isn't accounted for by fret placement.

    Evidently I have way too much time on my hands tonight, but what the hey?