Need microphone advice for capturing audio from students

[rubenmiranda]

The environment is a classroom. I purchased a Shure wireless receiver with a PGX4 body pack and lavalier mic which works great but only picks up audio from the teacher but not the students. I contacted Tandberg to ask about the Audio science ceiling mount microphone but the sales person laughed as he rattled off the price and told me to just buy a regular microphone and put it at the front of the class. I think I need a mixer in order to continue to hear the teacher's mic, and I know I want minimal wiring on the ground to avoid any accidents. I would really appreciate some tips on how best to approach this.

Thanks!

[tom9933]

Well you have several options and the decision will be based on not only audio quality, but also your budget. In all of the options below you will need some sort of mixer. I would recommend an active mixer (Clear One or Vortex) if your budget allows but any automatic mixer will work if your room isn’t too lively. Your options are as follows:
1) Ceiling mounted mics. While this solves the cabling problem you don’t have push to talk capabilities and the sound quality is general not as good a table mic.
2) Wired table mics. This is probably the most common setup and also one of the easiest to setup. Generally a mic for every 2 to 4 students is a good rule of thumb but this can vary based on the student seating. I would also recommend using push to talk mics if you plan to do any multipoint calls. We generally install floor boxes in our DL classrooms to address the cabling problem. Another good option is to mount the tables off of the wall and run your cabling through the walls.
3) Wireless table mics. This is a more costly version, but fixes your cabling problem. You should also consider the battery life of the mics you choose to use. We have evaluated the Shure mics and were very impressed with the performance, but the cost and battery issues have made this an unattractive solution for us.

[Entropy3XD]

I agree with Tom on the ClearOne or the Vortex. I haven't worked with the Vortex myself, but some of the guys I work with tend to prefer them over the ClearOne as they say it is easier to configure. I have always been happy with the ClearOne mixers and their tech support has been outstanding. I don't know how much money you want to spend, but I can say that the Tandberg Audio Science mics are great, and they would solve any issues with cables across the floor.

[rubenmiranda]

Thanks for the replies. I should have mentioned how this is being used. We have several students who cannot come to school because of illness. We purchased an Axis 213PTZ network camera and a body pack mic which has worked well. We are now looking for a way for the student at home to hear the rest of the class (he can hear the teacher just fine) with minimal interruption to other students. I would prefer something that does not require pushing buttons or moving from one location to another for the students in the classroom. The classroom measures 23 x35 with a 10 foot ceiling. I spoke to someone at B&H and they recommended a Boundary microphone. I also looked up the Vortex mixer and Polycom keeps showing up (do they make it?). The price is about $3,000. I guess there really is no easy answer to this. The table mics sound good, but they are planning to move the equipment to another classroom sometime in the future. The audioscience sounds good for about $1,500, but the mixer is so expensive that I have to wonder if I can get by with a cheaper non-active two port mixer. Now I'm really confused. I guess I'll just have to try one solution and keep trying until I find what works for me. Hopefully I can purchase from someone with a good return policy.

[emello]

I have several classrooms with various configurations. In the simplest form, we just added a boundary mic (in a Tandberg roll around cart set up) and put that mid way on one of the student desks. Not an ideal solution, but it worked.

Another room has the Audio Science mic. This is a configurable classroom, and even when the student seating is changed, it still picks up a good size room, and works rather well.

In our distance classrooms, we have either the Polycom Vortex systems or the Clear One automixers. In some cases, there are ceiling mics with a lav for the professor. In a couple, we actually went back and retrofitted the rooms to add in push to talk mics, which make for much clearer audio for the far end. In moveable classrooms where we didn't have the PTT option, we mounted Clock mini-shotgun mics to pick up the students.

It all depends on what you really need (just need for these students to be heard, or heard well in a VC or webcast, etc.) and how much you want to pay.

[djackson]

. I contacted Tandberg to ask about the Audio science ceiling mount microphone but the sales person laughed as he rattled off the price and told me to just buy a regular microphone and put it at the front of the class. I think I need a mixer in order to continue to hear the teacher's mic, and I know I want minimal wiring on the ground to avoid any accidents.


I would stick with a ceiling microphone - Tandberg AudioScience as preference 1. Table mics pick up things great - paper rustling, students hitting the microphones, all noise you don't want. Students don't like using Push to Talk microphones.

We have all types of ceiling microphones going to Clearone XAP400 mixers - I have not tried the vortex but I will in the future. The tandberg audioscience microphones is simple, and it works great going directly to the codec. The only draw back is the size. It might not work in some rooms. It also works best with Tandberg vtc systems.

The Tandberg AudioScience is over priced for a PZM microphone attached to a piece of plexiglass. Try to get them to bring the price down major...maybe with another future purchase of vtc equipment. However, if you look at the list price $1,500, it is still competitive if you count how man standard mics and mixers it can replace, and give you better quality.

[Shawn Jones]

[QUOTE=djackson]I would stick with a ceiling microphone - Tandberg AudioScience as preference

The Tandberg Audio Science is only good for picking up sound up to ~14feet from the front of the mic. I would suggest some PZM's mounted to the ceiling grid, about every 15 ft or so. Should be able to get them from a local Crown or AT Dealer, or on the web.

-sj

[shogun2]

[QUOTE=djackson]I would stick with a ceiling microphone - Tandberg AudioScience as preference

The Tandberg Audio Science is only good for picking up sound up to ~14feet from the front of the mic. I would suggest some PZM's mounted to the ceiling grid, about every 15 ft or so. Should be able to get them from a local Crown or AT Dealer, or on the web.

-sj
The Audio Science mic works by concentrating the sound in the apex of the perspex. This is not available in a standard PZM. The TB documentation states that one AS mic takes the place of up to 6 ordinary PZM's. From my use of the AS mic I would have to agree.

[shogun2]

[QUOTE=tom9933]Well you have several options and the decision will be based on not only audio quality, but also your budget. In all of the options below you will need some sort of mixer. I would recommend an active mixer (Clear One or Vortex) if your budget allows but any automatic mixer will work if your room isn’t too lively.

I like the Vortex better than the Clear One. Better sound quality and setup. However, my first choice would be a Biamp Audia with AEC2 cards. Harder to set up and more expensive, but far better audio quality than both the others.

[Entropy3XD]

[QUOTE=Shawn Jones]
The Audio Science mic works by concentrating the sound in the apex of the perspex.

Please tell me I am not the only one who had to break out a dictionary for "perspex"?

Excellent word Shogun.

[Neil Griffin]

I'm dealing with the same issue as I upgrade a distance learning classroom. We currently have push-to-talk microphones, but I have been considering going to one of the ceiling microphone arrays. I read the comments about the Tandberg above. How does the one Polycom sells compare? I'm leaning towards a Polycom VSX7000 codec, so I'm wondering if the Polycom would work better, or does it really matter?

I've been quite happy with the audio from PTT mics, compared to sites we connect to that have the older style ceiling mics that seem to pick up more paper shuffling, coughing, chair scraping, etc. than human speech. But between all of the abuse the mics take and keeping the wiring on all of the mics working, I'm not sure whenther I want to invest in more of them.

[Shawn Jones]

When you are laying out a large conference room, how do you array the Audio Science Mics? On opposing sides of the room pointed at the center? Down the middle of the room pointing at the rear wall, and 14' apart?

I am approaching a point where I have to make a decision on this, and asked for a demo from my rep.

[trapehzoid]

When you are laying out a large conference room, how do you array the Audio Science Mics? On opposing sides of the room pointed at the center? Down the middle of the room pointing at the rear wall, and 14' apart?

I am approaching a point where I have to make a decision on this, and asked for a demo from my rep.

The latter is the preferred method for microphones. Each should have ideally an exclusive coverage.. not overlapping.

To the other poster.. PTT mics will always give you the best sound (closest to mic, gated so almost no echo potential and low noise) but they can be a pain to live with and install. Ceiling mics are a compromise to be more substainable and easier to install.. and people do not have to interact with the microphones which in a classroom setting can be a huge benefit (shy people, etc)

[shogun2]

There is a Tandberg reference document on the AudioScience microphone that would explain the best installation method.
I agree with the quality capability of PTT microphones. However, in the classroom the use of PTT could be a right royal PITA. The beauty of the AS mic is that it does not inhibit interactivity at all. BTW, for electronics you should now look at the new Biamp Nexia VC - 20KHz echo cancellation built into the box. Looks to be a worthy competitor to the Clear One and Vortex.

[tonyi]

Just my two cents on the PTT thought. I'm personally not a huge fan of PTT because it now makes the students have to interact with the technology. And in the K-12 environment for many reasons that can become an issue. I'm a bigger fan of stationary mics of some sort. And yes i work for Tandberg so i'm a big fan of the Audio Science. That was actually designed originally for the Classroom environment.
But even if you don’t go Tandberg i would suggest staying away from PTT.

[AceVid]

Just my two cents on the PTT thought. I'm personally not a huge fan of PTT because it now makes the students have to interact with the technology. And in the K-12 environment for many reasons that can become an issue. I'm a bigger fan of stationary mics of some sort. And yes i work for Tandberg so i'm a big fan of the Audio Science. That was actually designed originally for the Classroom environment.
But even if you don’t go Tandberg i would suggest staying away from PTT.

I agree...I'm stuck supporting PTT along with zoom feature (some through touch to talk some through old AMX accent pro's and camera man) it's doesn't make life fun for anyone..users included..I'd take a audio science any day over PTT.

[shogun2]

Yesterday was interesting - I had to go and fault find an Insors installation using a Vortex and four ceiling microphones. This is the first time I had touched a Vortex for about four years, and I have never played with a ceiling mic system.
Well, in comparison to the TB AudioScience mic, well, there was no comparison. The AS mic would win hands down for quality. I also had problems accurately setting up the Vortex to stop some harshness coming from the remote end, and us sending to the remote end. This will have to wait for another day, as I think there seems to be some level incompatibility that is not helped by the mouth-mic distance. I also found two of the four microphones orientated the wrong way - actually facing the loudspeakers rather than away from them.
The last time I played with the Vortex I did notice some graininess of the sound - has anyone else experience that? It may have been the speakers (EVID 4.2), which I am not familiar with.
All my recent experience has been in commissioning the Biamp Audia systems with AEC2 cards, and we have not had any problems with sound quality.
All in all, this was a good chance to compare what I know of the AS mic and ceiling microphone setups. The AS mic is far superior.

[Neil Griffin]

When we installed our Polycom VSX7000 system a year and a half ago, it replaced an older system with PTT mics. I was very reluctant to give up the mics, since we had great audio quality compared to many of the the sites we connected to that used arrays of ceiling microphones. But, I was also tried of replacing cables ( we have a critter problem underneath the temporary building). In the end, I did choose to get Polycom's new ceiling mic, and overall I'm satisfied. The audio quality is pretty good, and it is nice to have some flexibility in moving furniture around.

[Shawn Jones]

I just got a note from a Tandberg tech stating that they would rather not have the AS mics put in outboard auto mixers. That they suggest they be directly plugged in to codecs.

Iin the rooms that everyone has AS mics, what is the speaker configuration? Ceiling, front of the room speakers?

[Neil Griffin]

In my case, I am using the TV monitor speakers.

[Shawn Jones]

The challenge I have, its a large room, no stationary non-movable furniture. Front projection screen, front wall mounted camera, full on media playback.

I have a medium sized room now with wireless tabletops, that work great when they are turned on, and batteries charged. The users have expressed that the batteries don't last long, and they always seem to have to change them.

I am trying to get a plan for this style of room that doesn't involve the use of a portable, battery powered solution. My other challenge is that we use ceiling speakers for the reinforcement of the far end, so ceiling mics end up being a challenge for echo cancellers.

HELP!

[kampson]

Have you looked into the Revolab mics?

They are wireless, push to talk(some options).
They are battery(rechargable) powered but are supposed to last 8 hrs
per charge.

Several different types of mics and configurations.

Have just starting using them. So far so good.

Jeff K