Page 1 of 2 12 LastLast
Results 1 to 10 of 11
  1. Collapse Details
    can someone xplain..line vs. mic input.. balanced vs. unbalanced?
    #1
    Default
    Would someone explain these so I have a better understanding?

    I heard you usually just leave the audio stuff to "mic input" but what is line input for anyway? When would you switch to line input?

    Also, i've heard the terms such as this is a "balanced" mic or cable... etc. Can someone explain what balanced and unbalanced is in reference to mics, cables, and plugs?

    Thanks! You guys are great helping other learn this stuff

    Take care,

    JM


    Reply With Quote
     

  2. Collapse Details
    #2
    Default
    Sorry guys, i'm new to this sound stuff..

    Can someone also explain Condenser...vs... Dynamic mics? What's the difference, etc.


    Reply With Quote
     

  3. Collapse Details
     

  4. Collapse Details
    #4
    Default
    Here's some quick & dirty on it:

    -A mic input accepts signals from microphones or other devices that output at "mic level", which is very, very low. So those inputs include a preamp, which boosts the mic level by roughly 4 to 10 times (depending on impedance/operating level, as discussed below), so it can be recorded at a suitable level.

    -A line input is a signal that is already at the higher level that a mic preamp would boost a mic to, such as a CD player, iPod (line out, not headphone out, which is much hotter), camcorder output etc.

    -A mic plugged into a line input will be almost inaudible. Something like a CD player plugged into a mic input will distort horribly. That's why the two level standards exist.

    -High and low impedance are match-up factors as well. Without going too deep, you simply need to use matching impedance devices together. Plug a Hi-Z mic (Z = impedance) into a Hi-Z input and so on.

    -Both line and mic inputs can be either Hi or Lo-Z. It's best to check the specs on each device, but generally the following applies:

    Hi-Z line level devices are usually connected by RCA or 1/4" mono plugs, and operate at a -10 DBv level. Hi-Z mics usually also use 1/4" plugs and operate at about -20DBv level (as do most electronic keyboards and electric guitars).

    Lo-Z line level devices usually use XLR plugs and operate at +4 DBm level. Some use stereo 1/4" plugs. Lo-Z mics almost always use XLR plugs and operate at about -50 DBm level.

    You can see form the above that basically, you can't intermix line/mic or Hi-z/Lo-Z devices. There are notable exceptions, particularly when connecting Hi-Z line outs (*when properly rewired*) into Lo-Z line ins and vice-versa, but otherwise the former is the rule.

    Hope this helps
    Last edited by Ted Spencer; 02-13-2008 at 01:39 PM.
    "Behind the shelter in the middle of a roundabout
    A pretty nurse is selling poppies from a tray
    And though she feels as if she's in a play
    She is anyway"

    From "Penny Lane" by Lennon/McCartney


    Reply With Quote
     

  5. Collapse Details
    #5
    Sound Ninja Noiz2's Avatar
    Join Date
    Jan 2006
    Location
    Detroit & SF
    Posts
    4,736
    Default
    The only thing I would add is that mic levels are typically measured in millionths of a volt and line levels range from roughly 1/10 to a couple of volts so the difference can be a lot greater than implied above.
    Cheers
    SK


    Scott Koue
    Web Page
    Noiz on Noise
    Bugín out of Babylon



    ďIt ainít ignorance that causes all the troubles in this world, itís the things that people know that ainít soĒ

    Edwin Howard Armstrong
    creator of modern radio


    Reply With Quote
     

  6. Collapse Details
    #6
    Default
    Right. There are large differences in output levels between various devices within a category, so my descriptions were general in nature.
    "Behind the shelter in the middle of a roundabout
    A pretty nurse is selling poppies from a tray
    And though she feels as if she's in a play
    She is anyway"

    From "Penny Lane" by Lennon/McCartney


    Reply With Quote
     

  7. Collapse Details
    #7
    Senior Member
    Join Date
    Jan 2007
    Location
    Hamilton, Ontario, Canada
    Posts
    2,891
    Default
    Quote Originally Posted by Noiz2 View Post
    The only thing I would add is that mic levels are typically measured in millionths of a volt and line levels range from roughly 1/10 to a couple of volts so the difference can be a lot greater than implied above.
    Sorry to be picky, but most mic voltages are in millivolts which is 1/1000th, not a millionth. Millionths would be microvolts.


    Reply With Quote
     

  8. Collapse Details
    #8
    Senior Member SMuir's Avatar
    Join Date
    Dec 2005
    Location
    Toronto, Canada
    Posts
    740
    Default
    Quote Originally Posted by justmarvin View Post
    Sorry guys, i'm new to this sound stuff..

    Can someone also explain Condenser...vs... Dynamic mics? What's the difference, etc.
    Dynamic and condensor mics use different methods of transducing vibrations in the air into electrical signals.

    A dynamic mic's diaphragm is attached to a coil. Air pressure moves the coil back and forth through a permanent magnet, which induces an electrical signal.

    A condensor mic consists of a diaphragm positioned very close to a metal backplate, which is charged by an external voltage. This arrangement forms a variable capacitor, in which the capacitance changes reflect changes in sound pressure level. Condensor mics are sometimes referred to as "capacitor" mics.

    In more practical terms, condensor mics tend to be far more sensitive, and to have lower self-noise than dynamic mics. Dynamic mics, on the other hand, tend to be much more rugged and accept much higher sound pressure levels. Condensors mics require an external voltage to charge the capacitor (such as 48V phantom power), whereas only a few dynamic mics require external voltage. Most of the microphones used in production sound recording are condensor mics.


    Reply With Quote
     

  9. Collapse Details
    #9
    Default
    Although it should also be pointed out that Electro Voice RE-20s and Shure SM7s, both dynamic mics, are hugely popular in studio use for all kinds of video, TV and radio productions.
    "Behind the shelter in the middle of a roundabout
    A pretty nurse is selling poppies from a tray
    And though she feels as if she's in a play
    She is anyway"

    From "Penny Lane" by Lennon/McCartney


    Reply With Quote
     

  10. Collapse Details
    #10
    Sound Ninja Noiz2's Avatar
    Join Date
    Jan 2006
    Location
    Detroit & SF
    Posts
    4,736
    Default
    Quote Originally Posted by Steve House View Post
    Sorry to be picky, but most mic voltages are in millivolts which is 1/1000th, not a millionth. Millionths would be microvolts.
    "In terms of voltage, the boost is from levels measured in micro-volts (millionths of a volt) to between 1/10 volt and 2 volts."
    section 11.2 pg 152 Sound Reinforcement Handbook

    Ted, I wasn't criticizing just emphasizing. There are some very hot mics out there that can close the gap considerably.
    Cheers
    SK


    Scott Koue
    Web Page
    Noiz on Noise
    Bugín out of Babylon



    ďIt ainít ignorance that causes all the troubles in this world, itís the things that people know that ainít soĒ

    Edwin Howard Armstrong
    creator of modern radio


    Reply With Quote
     

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •