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positioning of overheads

Discussion in 'Room & Overhead' started by sammyg, Nov 6, 2007.

  1. sammyg

    sammyg Active Member

    Hi Guys,

    My question is mainly in regards to spaced pair.

    The more I read about OH drum micing the more I read that both mics should be the same distance away from the snare drum to avoid any phasing problems and keep the snare in the centre of the stereo image.

    But I have a question, due to the fact that the snare is off to one side of the kit (most of the time) not always directly in the middle of the drumkit, doesnt this mean that the overhead mic on the "ride side" will fall short of picking up the other side of the kit? Know what I mean?

    Example, lets imagine we are looking at a right handed kit front on.
    Say I placed 1 o/h mic between the snare and hats (say 20cm to the right of the snare), this would mean I have to place the other o/h mic 20cms to the left of the snare yeah? But the remaining parts of the kit on the left side are way more than 20cms away, this mic would fail to capture them properly wouldnt it?

    Then I was thinking about a stereo mic and what one would do there.
    Say you had a rode nt4 stereo mic, to keep the snare in the centre of this microphones image you pretty much have to place it above the snare yeah? Again, doesnt this mean that the ride side of the mic is going to be a little less detailed due to the snare being off centre in relation to the entire kit setup? I dunno, im confused! Maybe there's something I just dont get yet!

    Would appreciate anyones contribution on this!

    cheers,

    SammyG
     
  2. TheBear

    TheBear Guest

    i might be wrong but im pretty sure spaced pair isnt so much equidistant form the snare but more so from eachother. the time delay between the two mics would be so minimal it would be very hard to distinguish it aurally. the biggest thign ive been taught about spaced pair is to make sure that you have a 3:1 ratio which im sure you knwo what that is if you've read about OH micing.
     
  3. Boswell

    Boswell Moderator Distinguished Member

    I think you are confusing phase issues with creating a centred stereo image.

    If you were to use an A-B microphone technique on a wide sound source such as a choir, the spatial image in the recorded sound would be created mainly by the different arrival times and amplitudes of the various voices at the two microphones. A sound from a voice equidistant from the two microphones will reach both microphones at the same time and with the same amplitude, and the ear of the listener will interpret this as being in the centre.

    In the case of the Rode NT4 single point X-Y stereo mic, the two microphone capsules are directional and are mounted at right angles, generating the spatial image by their different directional responses. The sounds from any source reach the microphones at essentially the same time, and the listener gets the spatial information purely from the amplitude difference between the left and right channels.

    Now come back to the drum overheads. You are presumably using condenser mics with a cardioid pattern. Off-centre sounds such as cymbals and some of the toms will indeed be nearer one mic than the other, and so from the A-B technique will correctly appear off-centre in the sound image. It is convention that the snare and the kick are centred in the image, and to achieve this, the distances from both of those drum centres is made the same ("Recorderman method"). Imagine a piece of string looped from the kick skin centre to the snare skin centre and taken taut to one OH mic position. If a knot or mark is made on the string at that point and the string loop moved over to the other side, the other OH mic should be at the mark or knot when the string is again taut. Of course, any separate kick and snare mics should be panned central. Depending on your mix technique, you may choose to delay the kick and snare mics by a few milliseconds to account for the extra time the sound takes to get to the OH mics in order to have all four mics in phase.

    It is not usual to set up microphones X-Y for drum overheads.
     
  4. RemyRAD

    RemyRAD Well-Known Member

    Just watch the Tonight Show, Conan O'Brien, David Letterman, et al. and you will see highly experienced engineers with drum overheads that are symmetrically placed (and most often AKG 414's LDC). Notice, no problem with that when listening to it at home. So like most folks, just do what you see on television and it will work. But don't murder anybody in the process, please.

    Conversely, I could play you any number of recordings that I have accomplished live, with only 3 to 4 microphones on a drum kit. Bass drum and 2 overheads and sometimes snare drum. That's all and it's out of sight sounding! Sure, you get extra balls from the microphones on the toms but that's not the be all end all. You just want other microphones on the drums to make you look more important.

    Importantly insignificant
    Ms. Remy Ann David
     
  5. sammyg

    sammyg Active Member

    Cool, thanks guys, more pondering to do now, but is a lot clearer!

    Cheers,

    SammyG
     

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