Monthly Archives: October 2014

Creating a Better Audio Experience in the Classroom

Audio in the classroom


Article originally published in the October issue of AV Technology MagazineAV Technology Magazine October issue

Electronic audio capture is becoming more important in the classroom. With VoIP (Voice Over Internet Protocol), trends in BYOD, and video production in education, there is an influx of “audio novices” setting up learning space systems. While this expansion is certainly good for users, it is a difficult situation for those not expertly aware of the challenges and nuances of audio capture.

The basic goal of audio is to always get the microphone as close to the source as possible. This sounds like a simple task, but in reality is the most difficult aspect of electronically reproducing a sound. So many variables come into play. The producer has to decide how much of the mic can be shown in the picture, if any at all. When multiple mics are used, echo and pickup patterns must be addressed. There are room acoustics to account for. This means that each application is a “one-off”. There is no “one-size-fits-all” mic solution.

Quit often in education facilities, the person setting up the system may not have sufficient experience in audio. The single largest challenge today is educating the audio novice in order for them to better understand what solutions are available and how to implement them. The old adage holds true here: People will accept less than perfect video, but if they can’t hear and understand the audio track, they will shut off the program. Learning objectives will not be met.

This is a basic “how to” tutorial for the novice audio engineer.

The Classroom

Though we are discussing audio in this article, it is impossible to address electronics communications without mentioning video. The days of audio-only communications is quickly disappearing. However, audio is in my mind still the more important of the two, and will always be. If you can’t understand what the presenter or program is trying say, the communication is useless.

VoIP is the accepted term for audio and video over the Internet, and tends to be used for collaborative communications. A one-way program is referred to as IPTV. I think a better term for both as a whole might be IPVAC (Internet Protocol Video Audio Communications). But for the sake of clarity, I will use the accepted industry terms.

Within that term are two subcategories: one way and collaborative. As we use these in the classroom, we need to understand how audio will be integrated. Video is relatively easy to set up, all you need to do is place a camera. Audio is much harder.

This article will address the audio for VoIP and IPTV, as well as recorded programming. The three uses that will affect audio and video solutions for the classroom are IPTV, Collaborative, and the use of recorded video as homework assignments using mobile devices.

With Common Core being implemented nationwide, and the move to create the “Connected Classroom,” understanding how to set up a connected classroom is essential. Adding IPVAC to the education experience will create endless possibilities.

IPTV One-Way Communication

With the right resources and training, anyone can create their own IPTV channel. It’s a great learning tool for the students; not only do they learn how to produce a TV show, they learn about internet marketing and how to drive traffic to a web site. This technology could be used for something as mundane and dated as the “sage on the stage,” or something more engaging. The programming is limited in content only by the creativity of the programmer. A class can set up their own IPTV studio in any corner of the room. The challenge here is that the space used may not be set up as a real broadcast studio with proper sound proofing and echo management. Yet the problems faced are the same as any broadcast studio faces. The challenge comes in when you are using a space as temporary location, managed by a novice audio engineer.

IPTV is great for teaching a media class how to create a broadcast TV program. The audio solutions here are established audio devices such as shotgun mics, lavalieres, and handheld mics. I don’t see anything new here in terms of devices. The twist here is getting a fourth grade teacher to understand enough about audio to properly mic a room. The most effective solution is a wireless lavalier mic for each of the speakers and a mixer. The MXL FR-500WK is an example of this solution. Of course, this may exceed the school’s budget. If that is the case, boom mics may be the best solution.

Huddle Rooms & Collaborative Spaces

Smaller meeting rooms that utilize collaborative communications are now being referred to as “huddle rooms.” I just started hearing this term about a year ago. I believe it’s relatively new. This, in my mind, is the fastest growing trend in the history of communications. We can now have multiple people in multiple locations talking to each other, sharing documents, and seeing each other face to face. It will be a huge benefit for the classroom, as teachers and experts from all over the world can now collaborate and address a classroom, and everyone in the conference can participate in the discussion.

We start with a mental picture of the set up. Everyone in the room is facing the front, where a monitor hooked up to a computer is located. Everyone is watching the person on the monitor. The simplest solution for this application is a single boundary microphone, hooked up through the USB port on the computer. Keep in mind that echo canceling is often included in software solutions such as  Lync, Bluejeans Network, GoToMeeting, and Google Hangout.

Once the number of people exceeds eight or 10, and the room expands out to over 25’ by 25’, a multiple mic solution is required. This is where things get much more complicated (and expensive). It will be challenging to get mics in front of each student. A solution may be multiple boundary mics, or individual “stick mics. Once you add multiple mics, each mic needs to have as narrow a pick up pattern as possible, to avoid the same voice being picked up by multiple mics. The goal is for the students to be able to interact with the conference. This could be achieved with a single mic that each student approaches when they have a question. It inhibits a free flow discussion. However, given the large number of students in a classroom, this may be the exact solution that works the best. Ceiling mics can be used. However, they have their own challenges, and may be too expensive and complicated to set up.

There is no perfect solution, or “Magic Bullet.” Each room is different, as are the requirements. It is recommended that the novice hire an audio expert to help design a system.

The Recorded Program & BYOD

BYOD video production is explosive in schools. Most every student has a smartphone (that records video) and computers for editing. It was once prohibitively expensive to require video assignment projects or video production in the classroom. With the proliferation of hand held devices in each student’s hands, it is now possible for everyone to be a filmmaker. But these devices by nature are limited in their ability to record a quality audio track. There are many audio manufacturers filling this need. Many are new companies and a few of the established brands are entering the field. Special products designed specifically for the hand held devices  are needed.

If the manufacturer wants to be agnostic, and make a microphone work through the 3.5mm analog jack, a TRRS plus is needed. All mobile devices have this jack for audio input. If the manufacturer wants to make it format specific, and plus in through the digital port, they need either USB or Lightning jack products. Up until now, Android USB ports were only used for data and power. It was announced that next year, some manufacturers will be opening it up to audio input as well.  This means that there may be more USB mics designed to work with portable devices in the future.

Mics for Apple products utilize the Lightning Port. However, the user can plug in the Camera Kit Connector, which is a Lightning port to USB adapter. With that, there are some mics that will work. At this time, the Camera Kit Connector will not work on the iPhone.

There are many manufacturers producing mics designed to work through the 3.4mm jack. Different kinds of mics for various applications include a handheld interview mic, a wired lav mic, and shotgun mics.

As these new technologies make their way into the classroom, it is important for the tech deciders in the educational environment to stay on top of new products making their way into the market. These technologies are crucial for the education of the next generation. It’s important that we make the most of them by using the best hardware available. With myriad products available and trends like huddle rooms, even the most experienced tech managers need to familiarize themselves with the new electronic landscape.

(MXL recently introduced a line of mics designed to work through the 3.5mm jack, called Mobile Media. We have a hand held interview mic, a wired lav mic, a shotgun mic, and a boundary mic. We will be adding a four channel battery powered mixer, and a series of 2.4Ghz wireless mics within the year. They have been well received by the market, and are filling the needs of both the casual user and professional who are using their hand held devices for video production.)

 

Become a Recording Star without Leaving Home, Part 3: Adding Video To Your Repertoire

Above, the first music video  on MTV is now available on Youtube. 

There are two media outlets that have changed the way we share and consume our music. First it was MTV. Launched on August 1, 1981 with the song Video Killed the Radio Star, MTV revolutionized the music industry by bringing music videos into our homes 24/7. This created a big demand for content. Bands everywhere went into production of their music videos.

But, the bands still had to have funding to produce their videos and professional representation to get their videos played. In that sense MTV was the same as radio, but with pictures. Not everyone could use it.

The next influential outlet is YouTube. Developed by former employees of PayPal, YouTube launched in February 2005. It allowed anyone with a video and computer to upload their video. Amazing! There was no barrier to sharing your music video with the world…almost.

There was still that pesky task of producing a video.

Enter The Digital Age

As computers became more powerful, video editing software started to come of age. Now, anyone could learn to edit a video on their home computer. Digital cameras and DSLRs became less expensive and easier to use. It was the perfect storm of cost reduction and technology advancement. Shoot a video, edit on your computer, and load it up to YouTube.

The addition of a high definition video camera to your iPhone put a professional camera in everyone’s pocket or purse. With advanced video apps, the transition from professional equipment to affordable consumer products was complete.

Apps, Apps, & More Apps

With the sophistication of iOS apps these days, a lot of your production can be done right on your device. You don’t even have to use your computer. Everything is on your phone.

1. RecoLive Multicam is a superb app that takes four iOS devices and tethers them on a wireless network. The audio track is recorded by the main device. That same device can do live, four-camera production in real time. Then save your video in HD and share it.

2. Want instant streaming? Switcher Studio also does four camera production and streams live to YouTube. This is great if you want to broadcast a live performance.

3. Another handy app is Videolicious. It takes photos and video from your camera roll and creates a slide show. Imagine shooting a series of photos and videos and adding voiceover audio afterwards. Then you upload that video to YouTube.

4. If you are using your iOS device, I recommend Filmic Pro as your production app. It has many professional camera features, such as variable frame rate, variable recording resolutions, and live audio monitoring. It is the live audio monitoring that I like the most about this app. With it, you can monitor the audio as it is being recorded to confirm an adequate audio program. It works great with our Mobile Media mics, which each have a headphone jack on the cable.

There are many more apps to choose from. These are just a few suggestions.
There are so many low cost options, where does an aspiring videomaker begin? First, determine how you want to present your music, and then look for the equipment or apps that will accomplish your vision.

Video didn’t kill the radio star, after all. Video makes the radio star!

Can You Hear Me Now?

Teleconferencing

The progression of the Audio/Video industry is fascinating.  The first broadcast medium was audio only…it’s called radio and it was used primarily in the home.  The first visual medium was film, and it was video only.

When they merged video with audio in film it was big.  When they merged video with audio in broadcast, they called it TV, and it changed the world.

In the electronics industry, we spend a lot of time talking about video.  First it was video itself.  Then it was color.  Then it was the VCR.  Then it was SVHS.  Along came High Definition, and it changed the way we treat video.  4K, 8K, 16K, and all those Ks will keep improving the picture.  Who knows what else it will do?  Only time will tell.  (Here’s a cool infographic on the history of television.)

Video is fun.  Video gets attention.

No one really talks much about audio.  The technology is old, it hasn’t changed much over the years, and it just isn’t as sexy.

But without good audio, life is a silent movie.

silentmovie

People will accept compromised video – grainy, shaky, or low resolution.  But if they can’t understand what is being said, they will turn it off. 

Whether it’s web conferencing or shooting video, proper mic’ing of the subject makes all the difference in getting the message across.

Rule number 1 in audio is to get the mic as close to the speaker as you can.

Rule number 2 is to keep the mic out of the picture as much as possible.

Rule number 1 and rule number 2 are in direct conflict with each other.  What’s a poor audio engineer to do?

That is where the compromise comes in.  Use a microphone that picks up the audio, while keeping it out of the picture or in an inconspicuous place.  How does one achieve this objective?  Pick the best microphone for the situation.

 Audio In Web Conferencing

The standard practice in web conferencing seems to be a low resolution web cam with a built-in pinhole mic sitting on top of a monitor hung on the wall.  Basically, that means the closest speaker is about 6 feet away from the mic and the farthest is 15 to 20 ft. away.  With a low quality mic that far away from the subject, the sound will not be very good.  Add to that room acoustics, people talking over each other, and paper shuffling during the meeting, and the result is a web conference that is seen and not heard.

MXL offers various audio solutions that are affordable and bring the sound closer to the subject.

A USB Boundary Microphone is the easiest way to get good sound, without a big mic sticking up in the picture.  It will pick up an area of about 25 feet, 180 degrees.  In most small conference rooms, that is all that is needed.  Place it on the conference table, and the sounds “bounce” off the table and gets gathered up in the mic. There’s no obvious microphone in the camera view so you’re achieving the seemingly conflicting goals of close mic’ing and discreet mic’ing.

USB Gooseneck Microphones are a bit more intrusive but can be placed closer to the person speaking.  This is a good solution for a small meeting of four or five people.  The MXL AC-400 gooseneck can be used with up to four AC-40EXT extension mics.  They look very professional and do not call attention to themselves, and they deliver the sound quality you need.

These microphones will meet the web conferencing needs of most small to medium sized businesses.

Once you get past these options, things get a bit more complicated.  In some cases, there is no way around a more complex and expensive solution, especially when the room is larger and there are many more people in the meeting.  In that case, a combination of table mics, ceiling mics, and a DSP is probably needed.

Our goal at MXL is to provide low cost, simple, high quality solutions for web conferencing.  One thing that has made this possible is the introduction of software programs such as Microsoft Lync, Bluejeans Network, and Vidyo, to name a few.  All of these programs have echo canceling built into their systems, eliminating the need for an expensive echo canceling solution built into the mic.

What makes web conferencing so popular is the low cost and simplicity that the digital age has created.  It can be done with nothing more than a computer, TV, camera, microphone, and broadband connection. Check out my post on video for web conferencing.

Because of the affordability, small companies are now adding web conferencing systems to their offices.  Large companies are expanding them out to all of the conference rooms and offices, instead of just one main room.

In short, if you are in the process of adding web conferencing to your office, remember that your conference is only as good as the sound.  Make sure to move that microphone off of the top of the monitor and down closer to the people.

Look for two new boundary web conferencing microphones coming very soon from MXL!