John, A few thoughts...
The choice between option a and the rest depends on the requirement, not on the implementation! Even in option b (lapel mic) the person with the mic needs to be able to hear the far end; if this is via a loudspeaker, that means the mic will hear it too and you will have echo problems. Option d: don't even think of using switches - put all mics through a mixer with linear faders and LABEL THE FADERS! While the person on the mixer has to stay awake, it's not an impossible task - I regularly do it for meetings where 20 people share 10 gooseneck mics and extra people are on mics on stands. However ... Whenever you change the 'acoustics' of your room (person walking round with lapel mic, muting mics, flying faders up and down) you are in danger of disturbing echo canceller balance. In principle, if you don't have an echo canceller and everyone else does, you can get away with it by muting the incoming audio while anyone at your end is speaking, and muting your outgoing audio when no-one is, but this adds considerably to the mixer operator's workload. Also the operator has a difficult decision to make if someone remote replies to you before your end has finished speaking! One consideration is how much your site's participation may disrupt the remote meeting; only experience will answer that! We also have a 150-200 seater auditorium from which we do meetings - mainly video conferences so far, but the principles are the same. We find that handheld radiomics are the only successful solution to getting questions from the floor to remote sites. Ceiling mics, rifle mics and mics in aisles on stands have all been tried and all work worse and/or are more confusing than handheld radiomics. Cheers Chris ____________________________________________________________________ Chris Osland Office tel: +44 (0) 1235 446565 Digital Media and Access Grid Medialab tel: +44 (0) 1235 446459 BIT Department Access Grid room tel: +44 (0) 1235 445666 e-mail: [email protected] Fax: +44 (0) 1235 445597 CCLRC Rutherford Appleton Laboratory (Bldg. R18) Chilton, DIDCOT, Oxon OX11 0QX, UK [The contents of this email are confidential and are for the use of the intended recipient only. If you are not the intended recipient do not take any action on it or show it to anyone else, but return this email to the sender and delete your copy of it.] > -----Original Message----- > From: [email protected] [mailto:[email protected]]On > Behalf Of John Hodrien > Sent: 10 February 2005 09:17 > To: [email protected] > Subject: [AG-TECH] Rigging up a Temporary AG Node > > > I have need to setup an AccessGrid temporarily, and was > seeking advice as to > whether it's even remotely reasonable. > > We currently have a multi-machine room based installation of > AG2 working just > nicely. But sadly it's in a room with a capacity of about > 12. I've had a > request to setup an AccessGrid in a completely different room in the > university for a conference demo with approximately 120 > people. I'm not > willing to tear apart our existing setup for one event. > > Now I'm assuming this room has a projector and a set of > usable speakers. I > guess I could setup a laptop/shuttle with a camera or two. > But what would > anyone suggest for the microphone end of the bargain? Do I > have any hope of > setting this up in any meaningful way without hardware echo > cancellation? > > I guess the three possibilities I see are: > > a) Read Only. It's just a demo, don't let anyone > participate. Hence no need > for microphones. Just view lots of other people having > a meeting. > > b) Just one person participating, with a small lapel/headset > microphone making > the echo cancellation a little easier. > > c) Multiple microphones with full on associated nightmare > > d) A gimp sat at the machine flicking switches faster than > colossus to mute > everything that doesn't need to be on. > > Rental Gentner? > > jh > > -- > "A good scientist is a person with original ideas. A good > engineer is a > person who makes a design that works with as few original > ideas as possible. > There are no prima donnas in engineering." -- Freeman Dyson >
