Good quality wireless Mics for PC

[cybermat]

Hi Guys
not sure what title to put for this one really but you may have an idea of where best to look.

I have a meeting at work soon
one of our Dr's is teaching at one part of our hospital (theatres) and some of the students will be watching in another part of the hospital.
we have CCTV link already using HD quality cameras and a HD alien dvr with two way coms. the video quality is perfect but....

the quality of the plug in mics we have used so far was quite poor and the dr wants a tie clip type affair so she can walk about and point out bones etc to the students. to be fair we have only used maplins cheapest so far to test.

The DVR is based with the Dr in theatres and the PC with the students is in the education area.

Chap will stand at the front and the students will ask questions and the dr will reply from her area.

what I am looking for is a decent quality wireless tie clip type mic system that the Dr can use that will plug into the 3.5mm socket on the DVR.
and...
perhaps a wireless mic that the chap taking care of the students can use plugged into the 3.5mm socket of the PC (again decent quality).

I am just not sure when it comes to the wireless side what bits I need and what makes to look for I know Shure are supposed to be good but arent they just for proper amp systems - do we indeed need an amp between mics and PC/DVR etc to reduce feedback or noise or should we be ok?

We just want no screaming feedback and decent quality audio that everyone can hear reasonably well.
The student area has very good built in speakers next to a large cinema type projection screen so audio output in there is amazing.

we are also looking at good speakers to hook up to the DVR in the Drs area so she can hear the questions from the students clearly,but also not cause any echoing feedback in the student education area.

What do you reckon folks

 

[lucid]

First off, feedback... You won't solve that problem with a microphone alone. It's true there are mics that are less prone to feedback because they are less sensitive to sounds away from the direction of the talker, but put any mic in front of a loudspeaker used for sound reinforcement (which is what you're doing) and the result will be feedback. So as well as careful mic selection you also have to consider teaching the person talking about mic technique. That involves some basics such as not standing near to or in front of the speakers.

Second, the best type of mics to use to minimise the possibility of feedback are those mics that are used very close to the talkers lips. Watch any band performing and you'll see the mics used close up. They are directional and focussed on gathering sound from in front rather than all around. The further a mic is away from the audio source then the more it will pick up background sounds. That means a greater risk of feedback too and the more aware the person wearing it has to be about feedback. Tie clip mics by their nature are situated away from the talkers lips and so they will pick up background sound, and this includes rustling from clothes, shuffling of papers, keyboard tapping, footfalls, and any of those sounds that are reflected back from the room too. Better quality tie clips are less prone to this, but they all do it to some degree. Have a think about using a headset mic as an alternative. The ratio of voice to background noise will be far better. As a side bonus the Doctor's voice will sound much richer because the mic will pick up the bass that gets lost in the distance to a tie clip mic.

The radio link part of this is fairly straightforward. There's 'point to point' (transmitter to single aerial receiver) and there's 'diversity' which isn't the street dance group but two or more receiving antennas with some electronics in the receiver that discriminates between good and poor signal paths. This reduces the likelihood of the crackle from lost signals. The connection from either system to your relay/recording devices is just cabling. That's to say that the ends can be terminated in ways to make them suitable for any type of socket.


Brands to look at: Shure, Beyerdynamic, Sennheiser, Audio Technica. Price up from one of the first three, then get pricing on equivalents from Audio Technica. AT is good gear used for pro and semi-pro applications where you don't need the robustness (and cost) of top flight gear.

http://eu.audio-technica.com/en/products/category.asp?catID=4

 

[cybermat]

Superb reply sir.
This is new to me as it's not something I normally do but I would like to get right for them.
If it goes well the system will be used for regular teaching sessions and will be really useful to our junior Drs.

The inputs outputs on both the PC and dvr are basic 3.5mm sockets, the devices just act I suppose as a method of throwing the audio through our network.

On trial we were getting a lot of loop,echo noise etc so need to kill that next.

Many thanks for the great pointers.