Will this work? Please help!
Tim Harmon
OK - here's what the situation is...
A Church. The church is utilizing a point of source system that
consists
of two Peavey SP-2xt's flown over the center of the stage. The
speakers
are aimed
for coverage of the church which is about 80 feet of seating front to
back.
The mixer is located in the back of the church in somewhat of a "Crow's
Nest" -
meaning that the speakers are at eye level for whoever is mixing.
THE PROBLEM...
The speakers are aimed downward, but the guy on the mix is above, so he
doesn't hear
the highs like everyone else. How can you fix something that will make
him hear
the highs like everyone else so he can mix more effectively and
accurately?
MY PROPOSED SOLUTION....
What if:
A speaker was set up with the mixer in front of the sound man, and
the speaker was delayed for the correct amount as to be in time with
the
mains... Then, using a
analyzer and pink noise generator, an average real-time analysis was
taken throughout the congregational seating... then let the analyzer
(Such as the Peavey Autograph) take the analysis of what the soundman
hears now. The autograph can set a curve in memory and set itself up
to
give that response later. So put in the speaker in the crow's nest and
make it compensate for what you can't hear out the mains, giving
you a response that is closer to what the congregation hears.
Can you understand what I mean? Maybe that doesn't make sense. But
will it work?
It seems to work in my head, but I don't know. One guy told me to just
take a small horn and mount it on top of the SP2's and aim it toward
the
crow's nest. It will make it better I'm sure, but what is best??
Mike Maloney
Tim Harmon <peer...@cybertron.com> wrote:
> What if:
> A speaker was set up with the mixer in front of the sound man, and
> the speaker was delayed for the correct amount as to be in time with
>the
> mains... Then, using a
> analyzer and pink noise generator, an average real-time analysis was
> taken throughout the congregational seating... then let the analyzer
> (Such as the Peavey Autograph) take the analysis of what the soundman
> hears now. The autograph can set a curve in memory and set itself up
>to give that response later. So put in the speaker in the crow's nest and
> make it compensate for what you can't hear out the mains, giving
> you a response that is closer to what the congregation hears.
>One guy told me to just take a small horn and mount it on top of the
>SP2's and aim it toward
>the crow's nest. It will make it better I'm sure, but what is best??
I'm going to assume that the ideal answer (move the mix position into
the listening area) is not viable.
"One guy's" answer is better (although not complete):
If you use a nearfield speaker, then you will totally miss out on the
direct/reinforced/reflected aspect of the actual sound being delivered
to the congregation.
Frequency response is not everything.
So, as far as adding a horn:
The best way to accomplish this is to run a response analysis windowed
to show just direct level at the mix position, and supplement your
speaker array with the necessary component(s). This would require some
sort of high-tech analyzer, and someone who knows how to use it.
Assuming that these are not available, then the next best thing is to
get your hands on a real-time analyzer, check response within the
coverage area at a distance from the speakers approximately the same
as the distance from the mix position. Then go to the mix position
and check response there. Figure out what is missing (yes, it is
probably the upper end of the programme), and supplement the speaker
array with the necessary component(s).
If you use near-fields, even with an equalizer and delay, you might as
well be using headphones.
There are other factors to consider as well, such as "will the
addition of components significantly impact the overall
direct/reflected ratio - hence intellgibility of the whole system?"
A neat technique is to use a microphone within the listening area to
feed monitor or delayed speakers. It is not high on parts count, but
requires some thought and experience (or experimentation). A common
application is to use it for underbalcony systems.
Balcony face |
mic here |
> |
--------------------------------------------------------------------
^
under-balcony speakers
In this way, the people under the balcony experience the same
reverberant aspects of the main listening area. The microphone
eliminates the need for a digital delay. It does not, however,
eliminate the need for an eq - but on the whole, a very satisfactory
arrangement. Perhaps you could utilize this approach for your sound
booth.
Here are things to look out for:
1) Reflective surfaces behind the mic element - can color the
response immensely. If you want to mount close to a wall, you would
do better to mount on the wall and use an absorber directly behind it
(the PZM is lousy at this, BTW...picks up too much ambient noise and
reflection...in theory an omni should work fine but such has not
proved to be the case).
2) Mechanical noise: you will probably need to shock-mount the
microphone if mounted to a wall or ceiling...mechanical noise from air
handlers, etc. can be quite annoying.
3) A high-quality microphone is mandatory - AKG 460 is my choice
(although the Audio-Technica 4000 series condensers seem like they
would do a respectable job as well.
4) try to find a position that is within the coverage area AND is
as far from the congregation as possible: avoids the constant backdrop
of paper-rustling, throat-clearing, etc.
5) Or, you could go to the approach from which this is derived:
get a Sennheiser Binaural Head, and set it in a seat in the pews, hook
it up to some headphones, and go to work. The next best thing to being
there....
Mike Maloney
ElectroAcoustic Design, Inc.