Qu 16 and overheads

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This topic contains 47 replies, has 8 voices, and was last updated by Profile photo of Showtime Showtime 3 years, 9 months ago.

Viewing 15 posts - 16 through 30 (of 48 total)
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  • #92610
    Profile photo of Mike C
    Mike C
    Participant

    What is the spec on max SPL from your mike’s manual?

    If it is that hot why couldn’t you go straight to the line input.
    With some sort of impedance matching transformer device if needed.

    That mic has a spec of 150db max input!

    That mic needs phantom power….look back about five post.

    I think you are playing too loud:)

    You must lead a very sheltered live band musical life!

    #92611
    Profile photo of Showtime
    Showtime
    Participant

    8mv/pa for a snare mic is very hot. My opinion buy a external phantom power an connect the mike to line input. This mic is designed more for studio then live.

    #92612
    Profile photo of Showtime
    Showtime
    Participant

    There is an lp20 from earthworks.

    #92613
    Profile photo of Dado
    Dado
    Participant

    Let’s remove “playing hard out of the equation”.
    This is from yesterday:

    I am the first guy in the video. As you can see I am not bashing the drums too hard, but without some sort of pad the dm20 would send too hot of a signal for qu16 to handle. Zed12fx,though, handles it at -10db.
    In any case, what do you guys think about the attenuator that behaves as if it was on the path bewteen the qu16 and computer and not between the mic and the qu16?

    #92614
    Profile photo of Mike C
    Mike C
    Participant

    I just had a thought and did a little research.

    Maybe and this is guess but again maybe the phantom power supplied to the QU mic inputs
    can not delivered the current needed to operate the DM20 mic.

    Looking at spec for the DM20, a Shure SM81 and an Audio 4050 the speced phantom power
    current draw is….
    10ma for the DM20 voltage range 24 to 48 volt
    1.2ma for the SM81 voltage range 11 to 52 volt
    4.2ma for the AT 4050 only speced 48 volt with no voltage range listed

    I could not find the phantom power current spec for the either the QU or Zed mixers.
    Most phantom power supplies on audio mixers is coupled to XLR pins 2 & 3 using 6.8k current limiting resistors so that is getting you into the 10ma power limit range at 48 volt.
    Again maybe the voltage drop through the resistors is getting low enough that the DM20 internal preamp is starting to distort.

    You could check the mic line voltage with the DM20 connected by opening up the XLR connector on one end or the other of the mic cable and measure the voltage across pin 1 and pin 2 and then across pin 1 and pin 3.
    Turn the gain down on that mic channel and mute it as well so you don’t get any pops in the system.
    Maybe even play the kit and see if there is a change with high level audio input at the mic.

    #92615
    Profile photo of Mike C
    Mike C
    Participant

    For what it’s worth as for over all QU phantom powering of mics I have had about 24 condenser mics all in use at the same time with no issues. The mics were a mix of AKG535’s, AT 2020’s, 4033’s, 4050’s, SM81’s and CAD E100’s.

    #92616
    Profile photo of volounteer
    volounteer
    Participant

    @mikec

    Not really.
    I value my ears and my hearing.

    Most concerts are way too loud for safety.

    Louder is not better, just louder and more painful.

    #92617
    Profile photo of airickess
    airickess
    Participant

    Are you hearing the distortion on the channel in the recordings or when you are monitoring it through the QU?

    Even if you turn down the gain on the channel so you aren’t clipping is the mic still distorting? Have you tried the mic on other channels of the QU?

    If the mic is distorting even though the signal isn’t even close to clipping on the mixer then there’s something wrong with the microphone.

    #92618
    Profile photo of Dado
    Dado
    Participant

    @mike
    Not sure if I will be able to do all that by myself, but I know a guy who could help me do it.
    But, what are the conclusions in both outcomes; when the phantom power is being ok, or when it is not?

    I even thought of buying other manufacturer’s attenuator and if I get a chance – to try all this with another, 3rd mixer…

    #92619
    Profile photo of Mike C
    Mike C
    Participant

    Not really.
    I value my ears and my hearing.

    Most concerts are way too loud for safety.

    Louder is not better, just louder and more painful.

    I never said louder was better but in the live sound provider business
    you work ALL types of bands and music genres.

    For what it’s worth I go to extremes to protect my hearing, I wear ear plugs when running power tools, mowing yard, driving my cargo van, ect.
    Depending on the type of show, volume level and my duties at the show determine if and what type of ear plug I use all the way to custom fit molded attenuators.

    #92620
    Profile photo of Dado
    Dado
    Participant

    @airickess
    The distortion is everywhere, pafl peaks into red, it tears the master out, as well as through the mixes. And finally it is the wav-file when I record multitracks, etc…
    The only way w/o it, so far for me, was when I plug that mic into the other mixer (zedfx) gain it down to -10db and then send that signal to qu16.

    #92621
    Profile photo of Mike C
    Mike C
    Participant

    Not sure if I will be able to do all that by myself, but I know a guy who could help me do it.
    But, what are the conclusions in both outcomes; when the phantom power is being ok, or when it is not?

    The easy one is if the phantom voltage drops below the minimum spec for the DM20, the internal mic preamp is running out of headroom due to the low voltage.
    In that case an external higher current phantom power supply sounds like it would be the answer.

    If the voltage stays well within the spec operating range then maybe it is the fast peak voltage that is the clipping you hear.
    As was mentioned earlier, the ZED with a different pre amp and analog signal path may kind of “smooth” the peak over.

    I would do the phantom voltage test using the ZED as well.

    #92622
    Profile photo of volounteer
    volounteer
    Participant

    @mikec

    I do *NOT work excessively loud shows. Nor would I attend one.
    I had to go to a phish concert once (wifey insisted) but I had ear plugs AND ear muffs.
    It was still loud but back then it was just tolerable. We left at halftime anyway.

    I wear earplugs when I attend shows, but if it is so loud as to distort the mikes I would have left the building already.
    And of course when I was mowing grass I had shooters ear muffs on w 33dB protection.
    Driving my vehicle has never been so loud as to need any help with the noise there.

    85dBSPL is the max that should ever be needed no matter what those fake govt reports claim is safe.
    95dBSPL is where many people start having hearing damage.

    Not everybody is average. Using averages from invalid studies is not helpful to anyone.

    The typical drummer and garageband performer clearly think louder is better.
    The loudness war they started resulted in LUFs which was a nice idea but done badly.
    It helps some but is still too loud to be safe for many people although many do find it adequate.

    #92623
    Profile photo of Dado
    Dado
    Participant

    Btw the signal is not being distorted when I hit my snare in a pop-jazzy manner or if my rimshots aren’t as violent as they tend to get. But, with any louder shots, there’s like 50% chance it would tear through our iems.
    I guess I’ll try to at least borrow an external phantom power to try that, even though, with all that’s been said, that would have to work.

    #92624
    Profile photo of Mike C
    Mike C
    Participant

    I guess I’ll try to at least borrow an external phantom power to try that, even though, with all that’s been said, that would have to work.

    If you try the external phantom power supply try connecting it’s output to the mixer using the 1/4 inch line input jack.

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