Tech Blog: Field Recording with Lavalier (TRRS) Microphones

by William Guth

Field Recording Tools: Based on A True Story

It came to our attention recently that some faculty would like to record interviews with colleagues to include in their courses, a practice we highly encourage. As professional practitioners you have access to experts and colleagues with all types of experience who can add real world context and value to your course content simply by sharing a story.

One such faculty was travelling on business and scheduled a meeting with a colleague who volunteered to give some real world context to important lessons in their course. As the meeting was somewhat impromptu, we had little time to evaluate their recording options, and ended up with an acceptable, but low quality recording. For that reason, and many others we would like to equip you with the right tools for successful video production in the field.

Tools at your disposal

For the most part, we all have the tools to produce audio and video out in the field.  Laptops, tablets, and cellphones are ubiquitous in the marketplace and we all own at least two of these, if not all three.

As we have come to expect, all of these tech devices are equipped with built-in cameras and microphones, and while they were not specifically designed for field recording, they are convenient tools nonetheless. One less commonly known fact is that these built-in devices are poor quality at best, as they are often not the key feature of the device. In order to deliver a certain minimum quality of production it is important to know the limitations of our devices, and identify some accessories that can help us level up our production.

Recording with Cell Phones and Tablets

With the exception of laptops, the built-in camera lenses for cell phones and tablets are actually quite high in quality, which is what makes these devices excellent for shooting interviews and demonstration videos out in the field. Unfortunately, their built-in microphones are terrible. They are typically omni-directional mics with narrow frequency response that record sound from all directions in equal strength, giving very little precedent to sources in close proximity. These built-in microphones are designed to pass voice signals in the human speech range to our recipient’s device during phone calls as cheaply and lo-fi as possible, over data lines and internet. And for that reason we are willing to accept a certain degraded quality.

When it comes to video, however, the input electronics on these devices are able to accept a myriad of external microphones, allowing you to take control of signal quality during recording. After all, we wouldn’t buy these devices if we couldn’t play back music and videos. And for that reason, the quality of your interview or demonstration recording can be greatly improved by using simple microphone accessories.

The Proof

The instructional technologists at SPS have reached out to manufacturers, and tested some devices that we recommend having on standby in case an opportunity presents itself to produce an impromptu recording for your course. By donation we received three lavalier (lapel) microphones coming in at or around $50 to test and either praise or protest. And we picked up some compact directional microphones to test that will do or die by our recommendations.  

Have a listen for yourself to determine which microphones sound best to you.

Microphone
w/ TRRS Connector

Samsung Galaxy PhoneUsing Video App iPad ProUsing Explain Everything
Device (no mic)
Azden EX 503i
IK iRig Mic Lav
Shure MVL Lav Mic
Earbuds with Mic
Rode Mic Me*
Saramonic iMic*

* Compact directional microphones

Omni Directional Mic Comparisons

Lavalier Microphones

OMNI-mics

Azden EX503i

IK iRig Mic Lav

Shure MVL Lav Mic

Earbuds with Mic

Sound Quality

Good

Very Good

Excellent

Fair

Freq. Range

unpublished

30Hz – 16kHz

45Hz – 20kHz

unpublished

Design/Build

Cheap/Rugged

Cheap/Fragile

Fine/Fragile

Rugged, Cheap

Length

4’0”

5’6”

4’4”

4’4”

Price

< $50

~ $50

> $50

$5 – $15

Notes

Rugged

Rugged, Duel Input

Fragile

Rugged

Conclusions

All three of the donated lavalier microphones are excellent picks for personal field recordings, and are plug and play ready, requiring no special setup or software unless preferred by the user. Each have unique characteristics which justify its pricing and quality, and all are approved by Instructional Technologists at NU-SPS to deliver the quality recording results our students deserve from their educational multimedia.

Below I have provided a breakdown of each microphone identifying unique qualities and characteristics, followed by an “in-short” comparison summary and recommendation. Click on each to review.  

Microphone Reviews

At under $50 the EX503i by Azden iCoustics is the most economical lavalier microphone of the set, designed with the consumer user in mind. Don’t let its generic manufacture and appearance fool you, the unit is built to be rugged, used indoor/outdoor for studio/stage, and to take a serious beating and keep on ticking. It comes with a handy velcro strap for storage, but no travel case making it susceptible to damage if you don’t take care of it. I would describe the audio quality as very accurate sounding, bright, crisp, clean, and true to life. The mic is highly sensitive, which gives it the presence of sounding loud, but also has the downside of letting in some extra background noise which may interfere with your source. Intrusion from background and external noise is a side effect of any omni-direction mic, but in this case noise cancellation is the least effective of the three. Indoors no to worry, outdoor urban environment could prove challenging particularly if it comes to equalization in post production. As you heard in the sound tests the recording quality is both roomy and bright due to its high-sensitivity and broad frequency range, and perhaps most likely to detect intrusive wind or touch noise when the mic is moved or rubbed on your clothing. For most users this is not a detractor, and will lend itself to the documentarian or true to life recording style.
Coming in an approximately $50 the iRig Lav mic from IK Multimedia is fairly priced for both its quality and purpose. One unique feature of this unit is its ability to chain 2 mics together, perfect for recording interviews in the field to a single device. This feature is also a slight drawback in that the chaining component is bulky, making the cord a bit tedious to wrap up and store. Specifications also indicate the unit is designed for easy monitoring, but the monitoring delay is noticeable, so I would recommend against monitoring while recording. The iRig packaging  comes with a sturdy travel case which makes it good on the go, and IK Multimedia offers a price break when you order a pair for interviews. I would describe the sound quality as a bit thin, but with good noise cancellation and dampening which make it sound clearer and less penetrable by background noise. Its thin sound speaks to its ability to capture accurate sound in the vocal range, and limit intrusion some intrusion from external sources. Keep in mind that the unit is built by a company which targets both consumer and prosumer mobile devices users, and DIY recording musicians. The iRig Mic Lav is our top pick for faculty field recording. 
At over $50 retail the MVL by Shure is the luxury option for this category, and you get what you pay for. Of the donated mics the MVL by Shure delivers the clearest and most crisp recorded sound free of external background noises lending itself better to post-production work when necessary. By design the MVL is specifically tailored to the dynamic range of the human voice for film and video, albeit higher end then for mobile devices. I would characterize the construction of the MVL as finely constructed and for that reason fragile. It does come with a soft leather carrying case adding to its luxury appeal, but is not particularly sturdy, and may not withstand a beating from your backpack or purse. Shure are a renowned international leader in quality microphones and audio components trusted by audio professionals across music and film for high fidelity, durability and reliable performance. For that reason its quality is guaranteed, but could pinch your pocket a little.
For most of us, a pair of earbuds with microphone were distributed for free with our cell phones, and you either take it or leave it. For others you might actually spend a pretty penny on earbuds with mic, where the mic is a bundled feature, and not the sole purpose for the price or design. I personally can’t stand how earbuds feel in my ear, but my wife absolutely loves them for hands-free talking while driving. For the thrifty DIY folks out there, the earbuds with mic work in a pinch. If you’re like me, and the buds in your ear are uncomfortable you can cut the earbuds off above the mic, and paperclip the strand to your shirt as a makeshift mic clip. As you heard in our samples the frequency response is questionable at best, and you may not like the sound of your own voice after recording.
When it comes to shotgun directional microphones for consumer and professional level video, Røde is the gold standard and the VideoMic Me lives up to Røde’s reputation. While this mic prices out at just over $50 retail your results will be worth every penny. Pros: The mic plugs directly into your phone or tablet and comes with a simple clip that secures it to your device and will keep it from drooping or flopping around. The polar pattern is unidirectional which means it will sound best pointed directly at you, or your sound source. That said, if you are interviewing one or two people the polar pattern is wide enough that you will get great sound even from voices who are sitting a bit off access. The unit comes with a furry windsock that is customized for the unit and secures tightly to the device. Cons: the unit is a few inches long, and depending on where your headphone jack is in relation to your device’s camera, the device may appear on camera, obstructing the view. This is not the case for most iPhones, and is not the case for some Android Devices. If you are filming a voice narration or Vlog from behind the camera this will not be an issue for you. If you’re like me and you love Android phones, keep the location of your headphone jack and camera in mind when you buy your next cell phone or tablet. There are several good choices.
Similar to the Azden EX503i the Saramonic iMic is the budget choice for the compact directional mic category coming in at ~$20, and is an excellent value. The mic is not only compact and small, it has a flexible head you can tilt up to 90 degrees. For this reason in addition to its small size and stature this microphone will not obstruct the camera lens in any way. Technically, the polar pattern is not specifically unidirectional, but 90 degree. Typically 90 degree patterns are unique to stereo recorders, however this unit sums your signal down to mono. Precedence is still given to voices or sound sources directly in front of the mic, but will share a more equally distributed pick-up with voices or sources that are slightly off access so still excellent for multi-person interviews. And while the signal to noise ratio and manufactured components of the Røde VideoMic Me are far superior, the Saramonic iMic sounds great. You may notice some background noise introduced into your recording especially when recording in a quiet setting, but I can assure you this is not a deal breaker. In a lively or outdoor setting, this noise will be hardly noticeable, if at all.

Summary and Recommendation

The iRig lavalier microphone by IK Multimedia is probably the best pick for faculty field recording due to its ability to chain multiple units together for interviewing, sturdy travel case and reliable middle of the road sound quality. In terms of sound quality the MVL by Shure is the runaway hero of this comparison in terms of clarity, vocal range quality, and noise cancellation. If you have to have the best, and you don’t mind spending the money, the Shure MVL is your pick. All that said, do not discount the EX503i by Azden iCoustics. The unit is rugged, built to last and delivers perfectly desirable sound quality. There is no shame in the economical choice, and we will not turn away your multimedia recordings with this mic. Whenever possible we recommend against recording your earbud-mic combo, but if your voice isn’t too bass-y it could pass, and is probably better than recording with your built in device mic. Of course we can’t force you to spend the money, but a decent mic will go a long way and depending on the age of your kids you may find borrowed quite often.  

Check out this real life interview I recorded at OLC Accelerate Conference in Orlando, FL.



6 responses to “Tech Blog: Field Recording with Lavalier (TRRS) Microphones

  1. I really think it does come down to the iRig or the EX503i. I actually find the latter sounds better on in-ear buds and laptop speakers, although there is some noticeable high end missing on the female voice (hope it’s not just my hearing). Less noticeable on the male voice. I wonder if this is why the frequency range is not published for the EX503i? Anyway, the iRig is great quality, which will outweigh a slightly hotter recording any day for my money.

    I would like to try these mics out creating short video tutorials in my online class on using online tools like Nebula and Yellowdig. I would use screen capture software with a small inset of myself and rather than wearing my favorite headphones and wrap around mic, I could have the lav mic and appear to be just speaking to the students while guiding them through the onscreen demonstration.

    1. These are excellent observations of the tonal quality. The Azden does sound muffled in the higher frequencies, sounding almost heady without that natural blend of nasal quality we’re accustomed to hearing.

  2. The MVL by Shure sounded the best to me.  It has excellent fidelity, dynamic range, and low background noise relative to the other recordings.  The impact is that recordings for students are clearer, more precise, and easier to listen to, and this is important when a long recording is prepared so the student is engaged, focused, and not distracted relative to a poor audio environment.  Considering that the microphone is a key tool to record the audio, this is an important area to prioritize in terms of having good to best equipment to ensure the maximum impact on the audience.

    1. The microphone is absolutely a key tool. In cases where a video may be dark or grainy, the audio is usually the thing that keeps people engaged in the content. And unless the visuals are absolutely compelling, a lot of video content could be presented as audio only. Plus, if you consider the context of this writing, recording intelligible audio in interviews will make all the difference for students.

  3. This is a really helpful comparison, William. I compared the iPad Pro set and liked the Azden EX503i for its full, rich sound. I liked the Shure MVL Lav Mic and the clarity was similar to the Azden, but even with both sound sliders at peak, I could hear the Azden much more clearly.

    I had not thought of an audio interview (as opposed to a video interview), but that might be an option. For instance, I teach a business communications class, and my brother has a great business anecdote that illustrates points about clarity in writing. The quality of the story is improved if my brother is relaxed. A mic is much less intrusive than a video camera and may result in a less stiff or canned quality.

    Two things, William, you might comment on are

    Recording such an interview over the phone, and
    Options for editing audio recordings.

  4. In SPS, or for any NU project, you can substitute the traditional phone call with a BlueJeans phone call to record your conversation.

    A faculty and I recently produced a podcast interview series for MSPA 472 (2017 Summer), and you can get an in depth glimpse of the project at TeachX 2017 as it will be presented in a digital poster session. The faculty wanted to interview alumni of the MSPA program who are working in the field, and could speak to aspects of entrepreneurship in Predictive Analytics. We used BlueJeans as the audio bridge and recording device. Both parties were instructed (encouraged) to call in from a landline to ensure audio quality. Then we downloaded the recordings, extracted the audio, and edited. One interview subject used a USB headset mic, and the difference is discernible due to noise gating inflicted by BlueJeans. The average audio consumer might not notice such a thing, but if I were to point it out to you, you would notice one any time you hear one for the rest of your days.

    There are several software options available for editing and enhancing audio through NU, and for free online. Audacity is a software available free online. Its a well known, community supported software with excellent documentation. The Annenberg School for Communication and Journalism at USC prefers it for their students who are not audio professionals, but find themselves in a situation to produce audio projects. NU faculty can download and use Adobe Audition (Au). Audition is an extremely powerful tool, and Lynda.com (also free to faculty) has excellent tutorials and practice exercises. You could use Camtasia to edit your audio clips. There would be less precision and flexibility available to you, but it works in a pinch. For our local staff, the computers at the NU library are fully outfitted with software, bring your own headphones. And, lastly, there’s a lesser known audio recording booth, and audio editing computer in the library that can be reserved. It almost never gets used, and they still won’t take walk-ins.

    In terms of recording interviews using traditional landline phones — The first item to consider are the laws, state by state, in regard to recording phone conversations. In Illinois as long as the interviewee consents to being recorded they cannot legally contest the lawful use of the recording. The university would require proof of consent for the content to be included in the course.

    The other aspect to consider is locating the tools to record. There are low to medium priced adapters for bridging the signal between a landline and laptop or portable recorder. And of course, there are the cell phone apps for recording calls.

    I have yet to test any of them, but have read extensively about them. The main issue with these apps, regardless of cost, is their output quality is generally low. I personally loathe cell phone audio quality. Primarily the issue lies with your carrier which has control over the amount of bandwidth your call is allotted at any given moment. And the path your signal travels regardless of distance is actually a treacherous one. Signals are split, then transmitted over microwave signals and reassembled on the other end. If the reassembly is off by just fractions of a second, it causes an echo sound in our handsets.

    TMI?

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