Hi I am new to the site and I want to hear anyones experience of Boundary mics as I have a conference coming up where I need to record a number of people round a large table. Any suggestions?
I'll second this request. I have not used boundary mics to date, but I would like to do something along the lines of the a poor man's version of Meyer's Constellation system -- something that allows me to mount area (mostly hanging but could be wall or prop mounted) mics to improve the sound delivery in the room just enough for comfortable hearing in the audience. I would like to use this for dramas and the dialogue portions of musicals.
Having been on several panel presentations, wireless lavs and SM57/58s on desk stands seem to be the standard, but for permanent installs you may want something better.
Unless you can get everyone to wear a headset or lavaliere mic, I personally prefer short goosenecks with the caridioid or even mini shotgun mic capsules for conference tables. Audio-Technica, Shure, AKG, Clock Audio and others offer these.
Flat mount boundary mics can work well, but have limitations in some conference table applications. One if the biggest is that they sometimes get inadvertently covered with papers, notebooks, etc., then people wonder why no one can hear them. People also tend to push low profile mics out of the way to set down their coffee or laptop and the users often don't realize they have a front, especially with the circular mics. If you try to cover too large an area with a boundary mic, such as an "omni" (actually only half omni since it's on a table) in the middle of the table you can start to pick up lots of extraneous noise. A gooseneck, even low profile, helps make people think "microphone" and they inherently know what it is and that they talk into the end of it.
There's a lot more to a Constellation system (or LARES or ERES) than multiple mics. Area mics can be very effective, but can also add a lot more work for the person mixing.
The system designer for my theater said CrownPCC 160's. I've talked to several local audio guys and all agree they are one of the best all around boundary mics. Unfortunately mine don't arrive for a month so I can't tell you how well they work first hand.
The PCC-160 is a great stage floor mic and one of my favorite boundary mics, but it is actually the various PCC-130 and PCC-170 models that are the CrownPCC versions intended for conferencing and tabletop applications. I would still suggest looking at the application and whether boundary mics are the best approach. They may be a good solution, but may not be if there will be a lot of stuff on the tabletop.
Also consider that if you pickup multiple people with each mic, then you will get every comment, sneeze, cough, etc. from any of them. In some cases it may be preferable to have a mic for every one or two people and to be able to mute the mics of inactive participants.
While the CrownPCC mics are great, it may be worth looking into the CrownPZMline. They are designed to work at optimum efficiency on surfaces like tables, and were designed with recording such things as conferences in mind.
One common mistake with boundary mics is using too many of them, if you have them close together and as they are omni-directional you get phase cancellation which gives some weird results, so I suggest that 1 mic covering 20ft of stage is about right if you use them closer you get a "combing" effect which is uncontrollable, I know, I've done it.
Like most things acoustic there are few rules but some guidelines, the best method is trial and error until you find the best way for your space,I was pointing out a potential trap to be aware of with boundary mics if you have many live at the same time it can sound weird.