USB Wireless Mic for Classroom Presentations

xTag USB MicWe offer a workshop that demonstrates how to make a narrated video from your PowerPoint presentations.  In it we recommend two ways of capturing your presentation with narration, either natively using the tools built in to PowerPoint in Office 2010 for PC or Office 2011 for Mac, or using Camtasia.  The problem is—if it really is a problem—that you must sit at a desk equipped with a computer and mic headset and deliver your lecture using PowerPoint, and then produce the video for web consumption.  Why might this be a problem?  Because there is no live audience.  We have noticed that teachers like audiences (i.e., students).  It can be difficult to deliver a lecture alone in a room, or worse, in a shared lab environment, because it just does not feel natural without having the students there.  The ideal would be to deliver the lecture in front of your students while recording it at the same time.  Just fire up PowerPoint, then Camtasia (recommended) and talk away.  You can always edit it down later before producing the video.  What’s the hitch?  The microphone.

Our classrooms are not exactly wired for sound.  It seems to be one of many forgotten components in our AV strategy.  In order to record your voice while lecturing we recommend a USB microphone, but obviously it cannot be a wired microphone, unless you think wearing a microphone headset while lecturing might make you look cool.  It is doubtful that any professor can look cool, and adding a headset cannot help.

Our solution to this problem is the Revolabs xTAG™ Wireless Microphone System, pictured above.  We have been testing this microphone for a while now and find its performance and sound quality to be excellent.  Here is the story.

The box contains:

  • The charger/base receiver station that you will plug into your computer;
  • A USB cable for the same;
  • The microphone (about the size of a tube of lipstick with a clip for attaching it to clothing);
  • An earpiece with volume control that you won’t need (unless you later decide to use this mic for Skype or other purposes);
  • A lanyard that no one would be caught dead wearing.

The base station is used for storing and charging the mic.  The bottom of the mic has a port that mates with a receptacle in the base station.  An unfortunate design feature also places the earpiece port on the bottom of the mic, meaning that it must be removed each time you charge the mic, but as mentioned above, you will not need the earpiece for the uses we have in mind, so this is no big deal.  The base station also has a mute button and signal LED on it, to quickly and easily mute the mic—maybe you want to take some student questions or comments during the course of the lecture, but do not want them record.  Intelligently enough, the mic also has a matching mute button, so you don’t have to be near the base station to mute the mic.  It also has a signal LED to let you know whether the mic is muted or not.

The USB cable is 5 feet long, plenty long for use with classroom computers, and has a standard USB connector of the computer end and mini connector on base station end.  Power to the device is supplied through the USB cable (requiring 500 mA), so be sure to insert it into a USB port that can power devices (usually ones on the CPU or a powered hub, probably not ones on a keyboard, maybe maybe not on the ones on your monitor).

There is nothing to mic setup.  Simply plug it in to a PC running Windows XP, Vista or 7 or a Mac running (I think, I cannot find this documented) any flavor OS X.  After your computer finds and installs device drivers (neither my PC running Windows 7 or Mac running OS X 10.7.2 had the slightest problem), select the mic as your default sound recording device.

On the PC, go to Control Panel > Sound (from icon view) > Recording.  Disable any other mics currently used for recording, enable the Revolabs xTag mic, make the xTag your default mic, and test the volume on the Sound dialog box meter.  I noticed that even though the xTag did not display a high recording level on this meter, it’s gain and quality were very good.

Mic Select Sound Recording Device

To be sure your recording level is adequate, select the Microphone by clicking on it in the above dialog box, then click Properties > Levels and set a relatively high level.  I record at 80%.

Mic Recording Level

On the Mac go to System Preferences > Sound > Input and select the Revolabs xTag, adjusting its sound levels to suit.

xtag Mac Mic Input Levels

When recording with the mic, be sure output does not go through the computer speakers, so mute or disable speakers or else you may get a feedback loop or echo effect while recording.

The wireless mic provides encrypted communications to its base station (in case it is being used for medical transcription or any other sensitive information).  High quality, full duplex audio is provided from the base station to the computer.  The mic can communicate with the base station within about 20 meters (65 feet).  If you move it out of range the connection will be dropped and the mic will mute itself.  It will also beep 5 times every 30 seconds to remind you to return it to the base station.  It makes it hard even for professors to walk away with it still attached to themselves.  If, on the other hand, professor X has inadvertently walked out of range and returns in range within 15 minutes the mic will simply return to operation.  Otherwise, after 15 minutes, beeping will cease and the mic will turn off.  Unfortunately it is not impossible for prof. X to lose it.  When the LED indicator on the base station turns solid green the unit is charged.  It takes about 2 hours for a full charge, but an 80% quick charge takes about 45 minutes.  Once it is fully charged it can be used for about 8 hours before recharge is necessary.  The battery is a sealed Lithium Polymer battery and CAN NOT be replaced by the user.

Microphones come paired to their base units to prevent interference from other nearby devices.  If a number of xTag units are used in the same room there is also a means of reducing power levels so that they will not interfere with each other.  It is recommended that no more than three be used in the same vicinity.

Academic Technology has several of these mics for checkout to professors.  Just call us (x2862), or submit a request to our help system or email help system ( to reserve on for a test or project.  We will be glad to work with you on using Camtasia with these great mics.  To see/hear the xTag in action, watch the following brief YouTube video.

The microphone costs about $188.00, so unless you are going to be doing a great deal of in-class recording it is not something you will want to invest in personally (a perfectly good Logitech USB head set, like the ClearChat Pro goes for around $35 for Skype or office audio recording).  It is a great solution, though, for in-class or presentation style recording.  Please contact us if you need assistance uploading your PowerPoint videos to your web space, Blackboard, or YouTube.