Why use PA system?

Discussion in 'Guitar Gear Talk Forum' started by DrSaurabh, Dec 13, 2005.

  1. DrSaurabh

    DrSaurabh Wh@+s Up D0C

    Ok..i have two completely unreleated questions...
    1> y is that instead of using super powerful amps...or even connecting the line out of the amps the the giant speakers, most bands prefer to play their sound thru the stacks and then thru the PA system??

    2>how importand and useful are guitar stands?
     
  2. hindiRox

    hindiRox Banned

    Guitar stands are useful when you need to pee and dont have enough time to pack your guitar up. Its not a necessity. Its like a wallet. You dont need it but you still use it thinking its safe.

    PA is reffered to Speakers used to Output to a large mass. Generally A PA system is what you see in a concert at the sides and at the console. Stacks and Amps have Lower output. A PA will invite police invariably, but Stacks and COmbo Amps need not.
     
  3. aeg0

    aeg0 Guitarıng Alchemist

  4. golisoda

    golisoda Comfortably Numb

    Running a guitar directly into a PA system often results in a very poor guitar sound since guitar amps and thier associated speaker systems are optimized for a given tone quality (ie. 'coloring the sound' - which is another way to say distortion, but in terms that is pleasing, musically).

    http://www.colomar.com/Shavano/speaker_design.html

    Look into this site. I guess it should be answered and so much you need to know abt speaker and amps.

    I always liked guitar stands as they keep your guitar neck safe. Most of the guys and even me for that matter do not keep the guitar inside a case after every gig. leaning your guitar to wall might change tuning, spoil the finish or laquer, or prevent your guitar from falling. So I recommend every one who love their guitar to get one stand. And more over I can sleep peacefully knowing that no one will trip my guitar.
     
  5. abhijitnath

    abhijitnath Fighting GAS frantically

    For the first one-PAs give you a completely transparent sound. Guitar amps are built to overdrive and so forth. So players get the sound they want through the amp and then send it out through the PA. Also the miced sound of an amp differs significantly from the line out sound. Also guitar amps have a limited dynamic range (no tweeter etc) and so the sound is completely different. Which is why if you ever paly a piezo-equipped guitar through a guitar amp it sounds bass-heavy and squashed...you should send it through the PA which has a wider dynamic range
     
  6. hindiRox

    hindiRox Banned

    @ Mercury : Yeah.. Have you nticed how you connect to the amp kept on stage.. Look behind.. From that amp there is an OUTPU to PA thru Snake.. Generally we in India(cause we have no option) settle for just an Amp.. Others have Cabs, Racks, and everything to go thru before going to PA..

    Santana uses that Cabinet on the lower portion of the diagram..
     
  7. DrSaurabh

    DrSaurabh Wh@+s Up D0C

    ok......i get the reason y use amps...........most amps have a line out..........but in most concert vids and even the live ones.....ive seent that often a mic is kept in front of the amp and that is take to the giant speakers thru which u hear the sound.............y not just connect the line out of the amps to the input of these giant speakers.........wudnt that be the sensible thing to do.......given that amps have a limited range...........
     
  8. abhijitnath

    abhijitnath Fighting GAS frantically

    Not really
    The limited range of guitar cabs (actually the amps are fine, its just that the speakers in guitar cabs are usually 10" or 12", without tweeters or bigger 15" speakers like those used in bass amps) is a feature and a sound that guitarists actually like..its not a weakness per se.
    Also miking a cab sounds different from taking a line out..especially in things like controlled feedback etc etc.
    However the results are less reliable and take a lot more tinkering when miking..which is often not available in live situations. Most Indian bands I've seen on stage go line out afaik (not sure, because I dont watch too much live music) because of the limited setup time etc etc available.
     
  9. hindiRox

    hindiRox Banned

    They generally use both.. THe use the Mic to give you monitors sound.. The sound for the Stage Monitors generally come from the Mic.. And the PA gets the sound from the Line out.. Thats generally how it is.. Look in the console there are TWO mixers..
     
  10. abhijitnath

    abhijitnath Fighting GAS frantically

    Not for the pros in the west I think...afaik all of them mike the amps for the sound coming out of the PA as well. Because that is that the sound they have tweaked when recording in the studio and the true sound of the amp..not the line out.And of course there are two mixers for the monitor mix and the PA sound..but the source for both is the miced sound.
    It might be different for Indian bands playing at shows here of course...Ive already mentioned the fact that I dont wacht them them much.
     
  11. alpha1

    alpha1 I BLUES!

    Micing the cabinet is generally prefereable since that is what u hear. The Line out signal is pure signal where the one that comes from the speaker cabinet has some frequencies attenuated, some amplified due to natural resonance.
    Even in case of line-out, usually it is recommedned to swtich on the cabinet resonator.
    ofcourse the mic need to be ultra high quality liek Shure SM57, otherwise the mic will only lead to "coloring/distortion" of the origianl tone.
    however, the one biggest drawback of using mic is the feedback howls that are too frequent. Usually EQing in the PA system usually solves the prob + changing the mic/speaker position

    the answer to DR Saurabh - the gigs n concert require audio signal / audio system having power in order of 10000W
    i dont think anyone has manufactured an amp + cainet system for that much power
     
  12. hindiRox

    hindiRox Banned

    SM57 is not a short distance mic.. It will pick up unwanted disturbances.. They use ones which are similar to the ones used for Cymbals when miking the drum kit.
     
  13. chintan9

    chintan9 yay! i won the ipod!

    @hindi rox- That isnt true. Infact Sm57 kicks ass when it comes to micing amps.

    PS- I dont know if you know this but SM57 is great for micing drums(bass drum) too!!
     
  14. DrSaurabh

    DrSaurabh Wh@+s Up D0C

    ok.......so if i am buying an amp and need to play live....so what difference does it make if i go for a 10w or a 15w or a 30w amp and spend exponenetially more than waht i will spend on a normal 10 w amp.......if i can just line out the amp into the pa system.........coz then eventually it is oing to come out of a 10000W system...rt?:confused:
    y do we prefer to go for amps with high power?
     
  15. chintan9

    chintan9 yay! i won the ipod!

    Brilliant question!!

    Actually its a huge misconception that the bigger the amp better the sound( tone). To tell you the truth most International Artists use smaller amps!!
    The huge stacks of Marshall or Mesa Boogie cabs that one sees in a concert are usually just dummies. The artist goes through a mid size amp(heads) and then onto the PA(simple isnt it!). Sometimes they go through multiple amps and then onto the PA.


    I suggest you get a brilliant sounding 50w amp and MIC it!! Dont get me wrong here, A stranger cube 40w or 80w is not what I am talking about, I am talking more in the likes of a Marshall or a Mesa Boogie or a Carvin or a Peavey etc.......


    PS- Check out guitargeek.com for info on artist's rigs. You'll know what I am talkin about.
     
  16. hindiRox

    hindiRox Banned

    ^^^ True..

    SM57 used by Arcane Ritual vocalist is actually a good compressor..

    @ Dr. Saurabh : How often do you play concerts abroad? Cause in India, given time slots, NO guitarist ever uses his own Amps on Stage.. So at this point of time you worry about what sound you want in your Jam room/ Practice Room/ Home anything... I personally prefer a loud sounding amp.. Use one or two 40W strangers..
     
  17. nebuchadnezzar

    nebuchadnezzar G34r G33k

    I have a doubt..if you are just micing a small brilliant sounding amp into a high power PA..then well and good...
    But if you are actually using the small amp to drive huge speakers thru line-out..its not the same, right?..the low power might not be enuf to drive those huge speakers properly...:confused:
     
  18. hindiRox

    hindiRox Banned

    No its not the same.. You cant take a 10 W amp on stage and expect a good sound out of a PA.. Logically it should answer your question..
     
  19. nebuchadnezzar

    nebuchadnezzar G34r G33k

    Thats why i raised the question....
    I guess the perception that small amps dont sound good comes from the fact that small combo amps usually have small shitty speakers..
     
  20. hindiRox

    hindiRox Banned

    May or may not be true.. A Laney Amp has good speakers in the low end models too..
     

Share This Page