Odd harmonics vs Even harmonics

Discussion in 'Guitar Gear Talk Forum' started by alpha1, Jan 27, 2006.

  1. alpha1

    alpha1 I BLUES!

    Yest I did some experiements with my processor.

    I recorded open low E string using different amp sims in the processor and then took the graph of the soundwaves produced.

    But before I come out with what I found:

    Axiom 0: sine/cosine wave is teh purest sound wave: like a bell chime or better: tuning fork, if you have heard it.

    Axiom 1: None of the sound waves are pure sine or cosine wave.
    Every wave from a guitar string has some higher harmonics content.

    Axiom 2: Even harmonics added to a pure sine wave cause a saw tooth shape.

    Axiom 3: Odd harmonics added to a pure sine wave cause a square shape.

    http://en.wikipedia.org/wiki/Musical_acoustics



    So I recorded the clean signal. And as expected it was not a pure sine wave, but looked like sum of two or waves (2nd and 3rd harmonic)

    Played Overdrive, the waves beacme taller and more uniform (that is low and high volumes were equalized ---> compressed by teh overdriver)

    Played thru Marshall sim ---> the waves were more of teh sawtooth variety.

    Played thru Boogie sim ---> The waves were more of the asymmetric square variety.


    From the wave graphs it looked as if teh Marshall had more of even harmonic content than Boogie.
    Boogie had more odd harmonic content than Marshall.

    But from the tone, I found that Boogie sim has a tone which appeals more to me.


    This leads me to conclusion that:
    The thing about even harmonics being good and odd harmonics being evil is total baloney. Both need to be there to produce the "distorted" tone.


    Anyone else has had any experience on this?
     
    Johny Bravo likes this.
  2. death_metal_fan

    death_metal_fan oh goody, it's a woody!

    I didn't even know there are things called odd harmonics and even harmonics. I think I'll skip the physics lecture and get back to playing the instrument. :p:
     
  3. d_ist_urb_ed

    d_ist_urb_ed Genuflect b*tches!

    @alpha, bro, you confuse me and in the process inspire me....
     
  4. alpha1

    alpha1 I BLUES!

    Do it mate.

    Try for yourself. It was quite a learning experience.

    U get to know that what we call as "A" string = 110Hz is not the case.
    The clean tone that is actually audible to us is 220Hz and 330Hz. The fundamental 110Hz tone has less amplitude.

    :grin:

    And when you kick in distortion all hell breaks loose on the harmonics front.
     
  5. Alfons

    Alfons C.F.H

    hmm...
    nice info...but didnt get some stuff clear though( will talk about it on messenger )..

    anywayz.
    You'll get better harmonics if you connect a delay pedal or use any kind of delay .
    It produces a much fresher and meaner pinch harmonic, after connecting the delay that is.

    Another thing is that, for some reason I get much-much better harmonics on my Roland Cube 15 than my Amt Metalizer even without the delay . Both have equal gain too .
    Need someone to Explain that ^^
     
  6. DrSaurabh

    DrSaurabh Wh@+s Up D0C

    dude.....like dist sayas.....am inspired too
    but sadly. dint get half of waht u said..tho i think its intresting......
    could u write about the basics too pleasss........and more indepth so ppl like me who know nothing can get it too
     
  7. dharmatma

    dharmatma Banned

    ^^ this topic is totally diff.

    http://www.mindspring.com/~j.blackstone/dist101.htm

    ^^ppl should check this link out to clear all doubts.

    the thing is even order harmonics have been considered to be more musical..ur case where u found the boogie sim tone to be more musical is ur opinion...there have been arguements on this topic.
    why do many ppl still swear by tube amps..coz they boost more even order harmonics..and sound more musical and "warm"..ss amp technology are workin on this very thing right now.
     
    CrYpTiC_angel likes this.
  8. dharmatma

    dharmatma Banned

    ^^this topic is totally diff.

    that was meant for alfons.
     
  9. alpha1

    alpha1 I BLUES!

    Dharmatma:
    What a coincidence. A few days ago I was talking to Ronnieanand on this funda of harmonics.

    + even bigger coincidence: We were also talkign about this Blackstone stomp box.

    :)

    d00ds visit the link Dharmatma has given, it will clear all the thigns that I have been tryng to say.


    Alfons: this is not about pinch harmonics etc. This was about standing waves on strings.
    It is a very detailed topic.

    All this Can be explained only in person. Or refer Resnick, Halliday, Walker.
    :p:
     
  10. zing

    zing Machine Head

    thnx guyz 4 the v interesting links....

    of cos this isnt true 4 nylon strings...

    this seems to b contrary to ur link dat says sawtooth has both even & odd

    also frm the link, sawtooth is sposed to be 'harsh' whereas the square shape is 'hollow sounding like wind instruments' - so mebbe its but natural tht u liked the boogie tone?
     
  11. alpha1

    alpha1 I BLUES!

    http://www.allaboutcircuits.com/vol_2/chpt_7/4.html

    http://www.computermusic.co.uk/tutorial/a_sforbeg/a_sforbeg.asp

    http://www.geofex.com/effxfaq/distn101.htm

    ^^^ Have a look at them too.

    Zing: All Standing WAVES whether in flute, piano string, guitar string, nylon or nickel, harmonica, etc have fundamental + higher harmonics

    The timbre of a musical intrument tells us qualitatively what is the harmonic content.
    Violin and distorted guitar have very high amplitude of higher harmonics.

    Acoustic guitar (with or without nylon strings) has very less amplitude of higher harmonics.

    Trumpet has very high content of highe harmonics. Flute has very little.

    I think by know you should be able to make out that the richer the sound, the more harmonic content it has.


    LOL I guess the links are from wikipedia, where common public writes the stuff. My mistake.
    Check the above links.
    They have been done by engineers.

    Take a pure sine wave at 110Hz. (Dull lifeless, boring) - Note: A
    Add a frequency double (220 Hz) - Note: higher A

    You will see taht the wave is tending toward the saw tooth shape.
    Add four times = 440 Hz. Note: Even higher A

    It will become very much like a sawtooth now.


    Instead of doublke and fourtimes frequency, add triple and five tiems frequency.
    You will see that the wave is becomign square.


    Tahts why the axiom: even harmonics -> saw tooth
    odd harmonics -> square

    Ofcourse perfect sawtooth wave will have even + odd harmonics (you can do fourier transform to check it)

    Now to the thign about solid state and vacuum tube amplifiers.

    Solid state distortion simply clips the signal - a sine wave will be clipped on top to make it similar to squaer wave.
    Thats why it is said that slid state increases teh odd harmonics content more than the even harmonics.

    VAccum tubes, on the other hand, distorts the wave form it self. A sine wave starts become a clipped saw tooth ..... or rather liek a parabola
    with the second half of the waveform being clipped assymetrically.

    Even harmonics distort the wave asymmetrically,
    Odd distort it symetrically.

    Hence tube amps genearte more even harmonics than the odd harmonics.


    Most of the guitarists liek the distortion from Tube amps.
    Hence it has been concluded: even harmonics generate a musically pleasing tone, odd harmonics genearte moer synthsized tone

    Thats what dharmatma said.

    But I felt contrary :p:
     
  12. Double Click

    Double Click New Member

    ^^^^^^ :think: :shock: :annoyed: :confused: :badmood: :insane:
     
  13. alpha1

    alpha1 I BLUES!

    WTF
    I thought you were electronics engg student.
     
  14. Double Click

    Double Click New Member

    :p:


    sorry, after reading those articles I couldnt resist :dance:
     
  15. alpha1

    alpha1 I BLUES!

    ABAY the least you can do is to acknowledge the fact taht I am a reputation whore.
     
    zing likes this.
  16. ronnieanand

    ronnieanand n00bier th@n th0u

    Shit.... I am not clear about Odd numbers, Even numbers and Prime numbers.... Now this guy confuses me with a lot of things.

    IIT ians are banned. Thread closed.
     
  17. Double Click

    Double Click New Member

    I'm reporting a BAD POST .... Lousy friggin braniacs...confusing me before my computer exam :mad:


    B'sides...u heard the man, no IITians allowed.. (always wanted to say that :)
     
  18. zing

    zing Machine Head

    hey alpha1 - good post mon tho i dint quite get all of it hehe reps 4 u :grin:

    yet as compared to other _acoustic_ gats, nylon strings do have a much 'purer' sound i think

    btw r u an IITian?
     
  19. ronnieanand

    ronnieanand n00bier th@n th0u

    Dont you understand that with the way he's trying to confuse about things which you have no clues about and about which he has no clues about it either.. :shock:
     
  20. alpha1

    alpha1 I BLUES!

    I dont have any clues about what clues you gave that clue-less Zing fellow.

    Says who?
     

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