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Confused w/ some physics concepts

  1. May 22, 2003 #1
    Confused w/ some physics concepts!!!

    I don't know anything about guitars,...can someone plz explain to me what is the different bet a acoustical guitar and an electric guitar (their amps, frequency...)? How amp play a role in an electric guitar?
  2. jcsd
  3. May 22, 2003 #2


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    Re: Confused w/ some physics concepts!!!

    An acoustic guitar uses a resonant cavity (a big hollow wooden body) to amplify the vibration of strings so that they're loud enough to hear.

    An electric guitar uses metal strings and a set of small coils of wire in a row, called a "pickup," to sense the vibration of the string. The signal in the pickup is an oscillating voltage, corresponding to the motion of the string, and is trasmitted via a cable to an amplifier. The amplifier's main task is to amplify the faint signal from the pickups and drive speakers so you can hear your music.

    - Warren
  4. May 23, 2003 #3
    The Sound hole of an Acoustic Guitar, and the structure of the guitar, wood/acoustic plastic/electric, combine to produce resonant frequency modulation fo sound. You can have strings of identical length, on identical size fretboards, but a Electric Guitar has less resonance because of the absent soundhole.

    This is where the amplifier retrieves the sound (soundhole in wooden acoustic acts as a sound amplifier, remove the soundhole on an acoustic and the soundwave is decreased, notes become un-focused), anyway the amplifier channels and focuses the sound into amp,then out through the speaker(take a look at speaker cone, recocgnize this? its the absent soundhole on the electric guitar) sound is focused via this cone/hole.

    The electrics involved in amplification can do all sorts neat tricks, like sending one part of a soundwave, through a delay channel, fan out the wave signal, reverse it, send it back up the wiring to the sound pickup on the fretboard, back on to your fingertips,down your arms, in through your spleen and out through your hip-bone( which should be close to the back of your 'strat', and if you time it so you flick your hip onto the back of the guitar, you can give the now weakening soundwave an added relativistic boost, or commonly known as FEEDBACK!

    This is happenning at the speed of light(electronics) and speed of sound(hippy..hippy..shakes).

    There was a genius in the sixties that started a new 'theory' based on a set of SUPERSTRINGS, he had a well documented 'HIP' replacement, which caused a 'magnetic resonance cloud' due to the alloy of the metal or something?, anyway people started using the term HEAVY-METAL, when they heard him play the stratocastar. Initially he tried to rectify the problem by turning his GUITAR UPSIDEDOWN so that the back of his guitar was opposite to his alloy hip-joint, but this just frustrated him more!

    In the end he started playing the guitar with his teeth, behind his back and even lubricating his Strat with lighter fuel! I know loads of people who went to his live concerts did not know of the HIP problems he was EXPERIENCING, but eventually he founded a complete new school of thought.

    This was later re-analyzed and called SUPERSTRING THEORY, it theorizes a connection between the early Universe Big-Bang (not to be confused with bang'n'oulfsen), anyway current hypotheses relating to this Superstring theory is that Guitar Strings are very important, and The Universe is the resonance of such a SUPERSTRING...a sort of BIG-TWANG theory if you like!!
  5. May 23, 2003 #4


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    I'm not exactly sure what the point was of this last post, or why you randomly capitalized various words. Further, it is apparent that your understanding of feedback (and acoustics in general) is not strong enough to permit you to act as a teacher to others.

    - Warren
  6. May 24, 2003 #5
    It is obvious that for some people a sense of humour cannot exist in their minds, they are so far gone on their egotistical supplement, they cannot see a funny side to anything, even when it is staring them in the face, and no amount of "Handwaving" will do to rectify this.

    I do NOT know if you can purchase a sense of humour online?..but the obvious responce you gave to the above post tells me your a far gone egotistical loser.

    I suggets you go out and listen to the greatest guitarist of all time Jim Hendrix, if this does not give you EXPERIENCE, then you have my sympathy.

    BTW THE spelling and CaP LOCK IS INTENDED TO MAKE YOU GRIND YOUR TOUNGE,hopefully you swallow this, you seem to be swallowing everything else!

    You are the One.
  7. May 24, 2003 #6


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    I have a lot of Hendrix, including the Jimi Hendrix Experience box set. It still doesn't change the fact that you don't seem to understand how guitars work, yet are still trying to teach a kid how they work. Shut your mouth.

    - Warren
  8. May 24, 2003 #7


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    Unfortunately, the needle on my truth-o-meter didn't budge when I read his post. Sorry.
    The horror! The horror!

    - Warren
    Last edited: May 24, 2003
  9. May 25, 2003 #8
    OK, but was it a finacial agreement?..I bet it is still in its cellofane wrapper, shame on you if so.

    The initial overview I gave was meant to be instructive, on a need to know basis?

    It is common knowledge that how you interact with your guitar and amplifer is an individual experience, this testement is bourne out by the "ROCK-U-MENTAL" heavy metal "tribute- TRIBUTE", band of the eighties, who legend has it took their name from the lead guitarist(Nigel) who "experienced" a similar event in my original post,SPINAL TAP was their name, ROCK-U-MENTAL was their game.

    If you get a chance to see their video(limited edition) you can see Nigel at the perfect moment when he just uses a single-finger, who whole of the band sound ended up going through the amps, bypast the engineer's sound check console(engineer nicknamed 'Ed-banger' had actually gone around into the auditorium,middle isle, front row, seat four, to see what the sound was like!) and Nigel was actually balancing the 'moment' on the tip of his finger! spotting the sound engineer 'upfront', he had to maintain this balance, and nodding his head towards the backstage direction, okay-ing to the engineer he was covering for him, Nigel achieved 'total-sustain', long enough for the engineer to run back around to the backstage engineer's room.

    It was after this event that Nigel was heard to mutter the immortal words 'I am phyically drained, where do I go to top that!', ignoring the reply from Derick Smalls,:You should get one in Saville Row I think!',
    Nigel and his knowest girlfriend left through the same door they entered, dissapearing through the front-man door for what turned out to be a long long time!

    If you buy your kid a GU-AMP (guitar-amplifyer) fer their birthday, you dont give them a 1000 page manual on electrical dynamics also? , and say:here you are kid, read this before you switch the amp on!

    No what you do is just after your neigbour complains about your kid kicking his football over their precious garden, and demanding you keep your kid 'indoors', you go out and get a guamp, place it in the kids bedroom, connect the amp to the mains, then after adjusting the guitar strap, place the 'strap-copy' over the kids shoulders, then holding the gu-amp lead in your hands, you give it to your kid and say,PLUG'N'PLAY boy, go for it!

    Then you rush out to your backyard, wait for your neighbour to emerge, and thank him/her for their advice on contempary education! then as you lean over the deviding wall, with a little smile and pointing your finger up to the sky, beckon your neighbour to listen, he just found his first M**f** note!, knowing your neigbour does not have a clue as to what M**f** means,it could mean Middle 'f' note? Middle finger note? Multi frequent note? Modulating Fretboard note?.... I'll that to you to decide :)

    Having mentioned above the heavy metal tribute, 'tribute' band, Spinal Tap, word has it that they are finalizing their re-emergence tour and LP release(they are trying to remain true to their roots, and the album will only be released on vinyl, no CD or DVD format, so if you aint got a old style record/vinyl player, to bad!), anyway rumour has it that they are near to deciding on the length and type of strings to be used on tour, this has been the reason giving to the press[ headline accusations that the ' in-band fighting' was the reason for the bands delay]
    to mainstream heavy touring.

    Nigel( amplead, and lead guitarist) was debating about the length and importance of guitar strings, he felt it important enough to go seek the ultimite string-length? This sabbatical Quest was initially instigated whilst he was online in one of those 'after-hours-chat-forums', he got talking to a far eastern philosophical student who was 'in' a monestry rehab clinic for wetern Has-beings(not the human type).

    Initially he was shown the computer by his current girlfriend Lolita(She was the inspiration to his solo tribute(flop) album:Current Bun, and the retrospective single; Whole Lotta Currents in Buns!

    Anyway ,Lolita showed Nigel the 'internet' so they could keep in touch while she finished her degree in Philosophy, she only had a short time with Nigel before she returned to Havard, but the mistake she made was to shown Nigel how to use search engine's, showing Nigel how to type in a word and follow links.

    The first time Nigel typed in the word LOL (this was the name he used to call his girlfriend Lolita!), Nigel ended up in cyberspace chatrooms, not only was he un-initiated in cyberterminology(nettiquette) his mode of thinking meant he was prayed on by the many youngsters who sensed an opportunity to have some fun. This was how he ended up on the ultimate trip, the search for the eternal string, apparently (I do not know if there is any truth in this, but?) in one forum somebody was descussing INFINITY, and Nigel assumed this related to the Acoustic String brand of the same name, and he had tried a large number of differing lengths.

    Cutting a long string short, Nigel has been trying to make guitar strings of infinity length! After 10yrs or more Nigel returned to England and sought out the remaining band members, and the current situation is that, I quote:Things are starting to happen!

    As I am at the end of this post now, this reminds me of the last impromptu press conference that Spinal Tap called , to announce the re-naming of the band, something that meant a lot to the band members, something dynamical and quote;[ in your face ] , the band are now called:THE NEW ELASTIC BAND! (REFERENCE IS OBVIOUS- reforming-bouncing back!), the invited press were told that the band had changed their name but not their style, still ' Rocking-U-Mental'. On the pre-press release flyer released by the bands manager LOL! the band stipulated, for 'technical reasons', the band would only answer one single question, no more and the band members could not speak directly, so their manager will respond verbally only after a band consultation to the question.

    So the press got together before hand and, after the band stood up to announce the groups new-name,(Lolita pulled down the curtain hiding the New name and Logo, Logo showed an elastic band snapping in the style of early eighties batman comic, you know the ZAP!-POW!-WOLLOP!andy warhole-logo style) so the press spokesman (also named Ed, but not sure if it was the same Edbanger from the concert above, or if it was the infamous fench guy Ed Ditor?) anyway up he stood and out comes the question the world really wanted to know, as Nigel had been the cause of such a long delay in reforming, and the stories and counterstories that were flying around the worldwideweb needed to be addressed etc.. etc.. the press thought up this little gem, and directed at Nigel:WHAT WAS THE REASON YOU SPENT SO LONG IN CYBERSPACE? WHY DID IT TAKE YOU NEARLY TEN YEARS? WHAT DID YOU LEARN?

    After the band formed a consultation circle to discuss the question(it turns out there are three questions
    but as one relates to music:Ten Years After, and the other questions are actually one when you analize the answer given by the band manager)..so after a few moments Lolita turns to the gathered press and chants out the sentence:Nigel now learned where the LOG-OFF button is!
  10. May 27, 2003 #9
    Truth is in my last post, need a clue? here it is [?]

    Answer is in the Question [?]

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