Re: [LAU] Update: video micing question

From: Thomas Vecchione <seablaede@email-addr-hidden>
Date: Wed Apr 24 2013 - 14:21:19 EEST

AHh lots of fun to respond to....

First off the topic of wireless mics. The microphones used on the TED
Talks is likely the DPA 4088.

Second on the topic of them being wired or wireless if they connect to a
belt pack. You will not be able to get the power and quality required out
of a headset unless you have something the size of a beltpack near it.
Mind you there are some small beltpacks and it isn't unheard of for me to
hide them in wigs on stage, see the Lectrosonics SM series for example.
But they are all many times larger than the mics themselves to provide both
quality, predictable and minimum latency, as well as required power.

I have put mics and beltpacks on dancers doing all sorts of manuvers. It
takes some time to get right, but if you take your time, and think about
things before hand you can secure them to instructors doing martial arts
just as well. The catch is, depending on what exactly they are teaching,
where you position the pack has to be carefully thought about, as one on
the small of the back or waist won't work very well if they will be
demonstrating basic breakfall techniques, etc. You would likely want to
look at the inside of the thigh, placed there using a mic belt.

In as far as restriction of movement, this is one of many things that set a
good A2 apart on broadway, they will take time to ensure that the cable is
secured close to the body where it needs to be, with appropriate strain
relief (On broadway this is likely tape, but you can use clips etc. as well
in places where hiding it is not as essential) where needs to happen so
that there is no restriction of movement.

In the end if an A2 has done their job right, the talent can forget they
are even wearing a microphone. But also this requires a fair amount of
prep work, and time with the talent. This may be something your
instructors are unwilling to do. In which case your best option may be to
use a shotgun or hyper cardioid, and follow the talent around. This may
itself be a distraction however, so a choice is going to have to be made at
where ever you are located and explained to the talent you have coming in
to teach.

If you do use an area micing technique, understand in order for it to be
effective you are going to have to actually mix the microphones. Area mics
do not get around physics, so if you want nice clear vocals, first they
need to be as close to the source as possible(Inverse Square Law) and
second you will need to only use a single microphone at a time(3:1 rule).

Now in as far as hanging choir mics and when to use them, and why they get
placed like they do...

Any area mic is going to tend to have a lot of gain applied to pick up a
wide area, thus the name. This does in fact mean that if you aren't very
careful about placement and speaker location, you will not get nearly
enough acoustic gain before feedback. If placed correctly however, they
can do a very effective job on picking up larger sources, ie. choirs,
ensembles, etc. Again you have to keep in mind the rules I mentioned
above, which means you can't put two mics closer together just for more
volume, especially if using a mono system(Stereo you can cheat a little).

Why would you put mics above the orchestra when the sound is point out?
Because not all the sound is focused out. Think about the vast majority of
instruments in an orchestra, most of them radiate sound in many
directions. And in fact the pickup from above the orchestra can be nearly
as good in many cases. If it was simply a matter of the sound 'moving
forward' only, then you would never see an orchestra in a pit, ever,
because most of the time the sound would only bounce around in the pit.
But obviously it doesn't do that. Sound is emitted not only by the bell of
many wind instruments, but also by the keys. String instruments radiate
sounds not only from the strings themselves, but thankfully from the
resonant bodies, otherwise we wouldn't hear a lot of sound at all.

So picking up the sound from above can be very effective, you wouldn't want
to be behind the orchestra because there are a few instruments that are
more directional in their sound, and the balance wouldn't be the same, not
to mention you would have human bodies for high frequency to get absorbed
by in the way, but slightly in front and a little above works well.
Especially true when micing a live performance where people are coming to
see the orchestra play, and not paying to see the microphones blocking
their view of the orchestra:)

Finally why use BT or not.. Well short version is, if talking about for
live reinforcement at all, it wouldn't be suitable. Latency requirements
for live reinforcement are FAR more restrictive than they are when your
listener can hear you 50-100mS offset and not have a clue because they
aren't seeing your mouth move, or hearing your natural acoustic sound for
phasing to occur. Live however this becomes a huge issue, and latencies of
that much would be completely unacceptable. Not to mention limited
bendwidth of many bluetooth headsets mean you don't get good quality at
all. If however these are acceptable limitations to you, sure try it out.
You may want to run tests on battery life, maintaining connection, etc. as
well though.

And of course for any solution, have a backup.

       Seablade

On Wed, Apr 24, 2013 at 1:39 AM, david <gnome@email-addr-hidden> wrote:

> On 04/23/2013 07:16 PM, Gene Heskett wrote:
>
>> On Wednesday 24 April 2013 01:15:04 david did opine:
>>
>> On 04/23/2013 03:26 AM, Gene Heskett wrote:
>>>
>>>> Another possibility might be a clip-on blue tooth device like the cell
>>>> phones use, but those are _not_ long range, with 6 feet about the
>>>> maximum practical range. I tried to make a dongle work over about a
>>>> 15 foot path here but could only keep it working for 2 or 3 minutes
>>>> at a time.
>>>>
>>>
>>> Then there's my silly JABRA EasyGo phone headset that works and connects
>>> just fine up to 100ft. I know that from personal experience, since our
>>> parking space is about 100ft from our house. I've sometimes left my
>>> phone there, and had my headset start beeping about losing connection
>>> about the time I get in the house.
>>>
>>> Similar experience at my office when I left my phone on my desk and
>>> walked out into the courtyard.
>>>
>>
>> That amount of power in a BT headset is probably sick bird, but if it
>> works, what the hey?
>>
>
> I don't know, it's my first ever BT headset. Supposed to be able to
> connect to 2 devices and work for listening to audio, but I don't have any
> other BT devices to try with and don't listen to music through my phone.
>
>
> --
> David
> gnome@email-addr-hidden
> authenticity, honesty, community
> http://clanjones.org/david/
> http://dancing-treefrog.**deviantart.com/<http://dancing-treefrog.deviantart.com/>
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>

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Received on Wed Apr 24 16:15:04 2013

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