Would you agree that bad audio can ruin a good video, presentation, or recording? Most certainly. A few months back, we identified tools for recording interview audio on the go. Today, we’ll listen to and compare five USB microphones, illustrate their uses in online instruction, and identify a few principles that will help us get the best results.
Why can’t I use a headset microphone?
For web conference purposes, a headset microphone will suffice, but not for much else. Reason being? Bit Depth and Sample Rate.
Combined, Bit Depth and Sample Rate are the principles at play when digitally capturing and preserving the richness and accuracy of recorded sounds. Even if the eventual output of your audio clip is low resolution (e.g. a musical greeting card or talking teddy bear toy), the objective is to record your audio at as high a quality as possible, then process it downward. And most headset microphones, not all, are designed with lower bit depth and sample rates.
Below are a list of terms and explanations which may be helpful as a reference throughout this post.
Glossary of Terms
Sample Rate is to audio as Frame Rate is to video. The more frames per second a camera can shoot, the smoother the scene will appear to the viewer. Similarly, subtle nuances and details that can be heard in a live performance or recording studio can be captured and better represented in playback,when recorded using a high sample rate.
Have you ever seen an old western movie where every few seconds the wagon wheels appeared to be rolling backwards? That visual phenomenon occurred when the frame rates were too low, sometimes as low as 14 frames per second (fps). High enough to capture motion, but low enough to make that motion to appear jerky or uneven 1. In audio, the signs of low sample rate present as sounding “under water,” unnaturally low-pitched, or distant.
Bit depth is to audio as pixels per inch is to photo resolution. The higher the pixel count, the richer the colors, and the more vivid the image quality when we view it on a computer or print out. Have you ever seen a photo that appears grainy? That can result from a photo taken in low resolution (fewer pixels per inch) or from being stretched beyond its original pixel resolution. The same can be said about audio. The higher the bit depth, the wider the range of sounds that can be represented by a recording, from the lowest bass to the highest trebles. As in photography, where deeper, wider ranging colors result in large file sizes, so to do audio recordings full of wide-ranging highs and lows.
Audio files saved to MP3 and AAC, for example, generally produce manageable file sizes, but technically constitute a loss in quality. Generally we accept this quality as passable, and the average person likely could not discern a noticeable difference.
Audio latency is a delay or lag affecting digital audio playback. In digital recording, this is generally caused by the computer’s sound card. When you speak into the microphone, the signal is sent to the computer to record, and returned back to you to listen, ideally in real time. If the signal you hear is sent back by the computer on a delay, it can sound like an echo of yourself, or as if you are having to talk over someone, which can affect your speech delivery.
Let’s hear some demonstrations:
- User experiences no latency in monitoring – Samson Go Mic Connect
- User experiences extreme latency in monitoring – Samson Go Mic Connect
You might have noticed the latency reading to be slower, possibly slurred. Trying to speak when you feel you are speaking over someone is very difficult to process, even when reading from a script.
“The polar pattern of a microphone is the sensitivity to sound relative to the direction or angle from which the sound arrives, or easier worded how well the microphone “hears“ sound from different directions. The most common types of directionality are: Omnidirectional, Cardioid and Supercardioid” 3
A Cardioid (or Unidirectional) pattern implies that a microphone is sensitive to sound coming from one direction, the front of the microphone, and will eliminate or be less sensitive to sounds coming from the sides, or rear of the microphone. In the case of cardioid, there is still sensitivity to sound from the sides, but is greatly diminished, and sound from the rear is generally eliminated. (see Microphones: Polar Patterns & Directionality concise visual representations)
Let’s hear some demonstrations:
- Two-way conversation using a Cardioid (unidirectional) pick-up – Samson Go Mic
The male voice is speaking from the front of the cardioid pattern, the female voice is speaking from the rear of the cardioid pattern.
- Two-way conversation using an Omnidirectional pick-up – Samson Go Mic
The mic is set to Omnidirectional, a 360 degree pic up. The Male (front of the mic) and Female (rear of the mic) voices are treated equally. You will notice some other room noise is sensed my the mic.
- Two-way conversation using a Cardioid (unidirectional) pick-up – Samson Meteor Mic
The male voice is speaking from the rear of the cardioid pattern, the female voice is speaking from the front of the cardioid pattern. The Meteor is built only for Cardioid (unidirectional) pick-up.
Sibailance refers to sounds created by producing air from vocal tracts through the use of lips and tongue which result in hissing sounds. Psst is a sibilant noise I use to get the attention of a cat. Other examples include (say these out loud): scraps, smell of steaks, storms, swells, mistakes.
When we form P, T, and B letter sounds a gust of air leaves the mouth. Just put your hand in front of your mouth and feel the blast you create.
Microphones convert moving air patterns into electrical patterns. The burst of air from P, T, and B sounds has significantly more force on the microphone element than other air vibrations made by a mouth. The sound of the air hitting the capsule is unnatural and distracting.4
A commercial pop-filter is a fabric screen often mounted on plastic or wire that you can place between you and the microphone to diffuse the explosive bursts of air created by plosives. Commercially, the fabric mounted by the manufacturer is selected for its ability to both stop air, and allow vocal frequencies to pass. However, one could slip a sock or available fabric over or near their mic to the same effect.
Pad in audio stands for ‘Passive Attenuation Device,’ which can be used to make an audio signal larger (+) or smaller (-). Generally this is a switch on a device that can be toggled physically, or in digital audio, a check box in a settings menu. The switch changes the circuit of the device to either boost or diminish electrical signals of audio based on their initial acoustic size. If the sound of a loud singing voice or an instrument is causing peaking or distortion sounds, the pad can be applied to ‘turn down’ or limit the intensity of the sound wave at the microphone. Also excellent for noisy environments.
A diaphragm is the microphone element that converts moving air patterns (or acoustic energy) into electrical patterns (electrical energy). When it comes to diaphragm size there is nothing better or worse depending on size. The main distinction is that a small diaphragm will represent sound more accurately, more neutral and uncolored. Whereas a large diaphragm can make audio come through sounding a bit larger, more beautiful. Large diaphragm mics are chosen to put lead vocals and solo instrumentation front and center.
Like cell phone calls, the bar for audio quality in web conferencing is actually quite low, sampling at 16 kHz per second. The richness in our voice is a considerably narrow band within the range of human hearing, so to transmit voice signals cheaply over long distances, 16 kHz is the minimum required for intelligible speech. But would you watch movies on TV if they were only as clear as a Skype or cell phone call? Face to face or on a personal call, as long as you can make out what is being said, we can use contextual cues to fill our communication gaps, and if we miss it we can ask people to repeat themselves or speak up. But when it comes to recording course content, we don’t have those luxuries.
For CD quality audio, and that which we record and stream online, the recommended sample rate and bit depth are 41 kHz/16-bit. For DVD video and recorded lectures and screencasts, 48 kHz/16-bit is the norm, but 24-bit also fairly common.
In recent development cycles, SPS faculty have taken to recording audio podcasts/interviews, screencast demonstrations, and are planning to host more sync sessions than before. For these reasons, we have recommended that faculty consider external USB microphones to improve the audio quality of their multimedia instructional pieces and presentations.
The microphones I have chosen to test and compare have a few things in common.
- A simple USB connection. Plug it in and record, so setup is easy as 1, 2, 3.
- All capable of sampling at 44.1kHz or 48 kHz and at 16-bits.
- Headphone monitor capability. Listen to yourself while you record to confirm clarity, gain and to make sure your audience will hear what you hear.
- Mac/Windows compatible.
- Price. Those compared here range from $40-$99, and the $40 options may give the pricier options a run for their money.
This comparison focused on microphones that met all five of the basic criteria, in order to narrow down the many, many options.
Compact USB Microphones (interviews/web conferences)
For Distance Learning faculty, a compact USB mic will go the distance, literally. Lightweight and collapsible, compact USB microphones like the Samson Go Mic and Go Mic Connect fit into your backpack, your purse, and your active lifestyle. The aforementioned microphones can clip onto your laptop or monitor, and stand steady on a flat surface. Both microphones mentioned also allow the user to toggle between unidirectional and omnidirectional polar patterns, which means you can record content solo and eliminate feedback, or conduct an interview between two or more people, depending on proximity and ambient conditions. Let’s have a listen:
The published frequency response for the Go Mic is 80 Hz – 18kHz, which implies that it is limited in its ability to capture or transmit some low end bass frequencies and some high end treble. Some might add this to the Cons column, but this actually confirms its bare bones, on-the-go nature, which makes it an excellent choice for normal vocal range, aids in transmission over internet lines, and helps to reduce files sizes when recorded.
Let’s hear the Go Mic in all three of its modes:
- Cardioid (Unidirectional)
Pros: The Samson Go Mic is a simple, multipurpose USB mic with excellent frequency response in the vocal range that performs as advertised. Lightweight, compact, plug and play, minimum acceptable bit depth and sample rates, Windows/Mac compatible, Zero Latency monitoring, multiple polar pattern options and -10db noise reduction. The Go Mic clips onto any laptop screen, and can stand on a flat surface.
Cons: The Go Mic can not clip onto a standard monitor, but can stand on a flat surface and is stand mountable. Another slight drawback is that the volume control for headphone monitoring is controlled at the computer, rather than on the mic.
Uses: Web conference, screencast recording, podcasts, lectures, and interviews.
While I would argue that the Go Mic Connect was designed to fill in a gap between the Go Mic and Meteor models, it would seem from their marketing that the mic is targeted towards real-time video game players and Skype/Facetime chatters unhappy with their device’s built-in components. For me, this model takes it a bit too far with its extreme gain sensitivity, and unforgiving omnidirectional polar pattern. The unit does come with a carry case that fits the mic and cable, but the shape and design make it difficult to pack tightly into a backpack or purse without worry of bending or breaking.
Let’s hear the Samson Go Mic Connect:
Pros: Like the Go Mic, the Samson Go Mic Connect is lightweight, compact, has minimum acceptable bit depth and sample rates, is Windows/Mac compatible, has Zero Latency monitoring (for PC only), and offers flexible polar patterns and noise reduction. The Go Mic Connect features an omni directional polar pattern with proprietary beam forming technology which effectively forms a shotgun style pick-up pattern, but is not technically shotgun. The Go Mic Connect clips onto any laptop screen, standard computer monitor and can stand on a flat surface.
Cons: Unfortunately, the drawbacks of the Go Mic Connect are simple, but major, and for some, they could be deal breakers. For starters, the Go Mic Connect requires a software download in order to maximize performance. The file size of the software is tiny, and operating the software doesn’t require any formal schooling, but it’s a step from plug and play, which so many prefer and desire. The software varies slightly from Mac to PC, which, while not an issue for most, could be irksome to those using both operating systems. The Go Mic Connect also has an extremely sensitive gain setting right out of the box. For professional podcasters or real-time video gamers with a shy sounding voice this can be an advantage, but it may take some experimenting to get the levels you like. And lastly, for Mac users, the latency in monitoring is echoey and unusable. When you plug it in, mute or remove your headphones and navigate straight to your system’s input levels. Otherwise, prepare for your ears to be left ringing.
Uses: Screencast recording, podcasts, lectures, and interviews.
Desktop USB Microphones (screencast/podcast recording)
Desktop USB microphones, you will notice, resemble traditional microphones in both appearance and design, and either come with a stand or are stand mountable. At this price point desktop USB microphones like the Shure MV5, Polsen RC 77u, and Samson Meteor tend to be unidirectional in their pick-up (or polar) pattern and offer tactile volume control for headphone monitoring. The main benefit of this cardioid pattern is that the microphone is most sensitive at the front, isolating from unwanted ambient noises and reverberant reflections that can cause feedback. This type of USB microphone is also optimal for hosting web conferences or recording voice podcasts and screencast demonstrations. In some cases, though, its size and proximity may be difficult to keep off camera. Let’s have a listen:
With a 25mm diaphragm inside the capsule, one of the biggest of any consumer model, the Samson Meteor captures and delivers rich, vibrant and accurate range for both voice and instrument recording. The design has a classic broadcast microphone look, and is manufactured with high grade metal, and durable plastic.
Let’s hear the Samson Meteor:
Pros: Just like its compact USB counterpart the Go Mic, the Samson Meteor is plug and play, has minimum acceptable bit depth and sample rates, is Windows/Mac compatible, and has Zero Latency monitoring for Mac and PC. The Meteor has a three legged tripod system that can fold down for easy storage, and is stand mountable to any standard threaded microphone stand.
Cons: The tripod folded legs can seem to be in the way when mounted to a standard threaded microphone stand, but that’s never stopped me from mounting one on a stand. The legs, when folded down, can also slip a little on a surface causing it to slump a little, in spite of the rubber tips on the feet.
Uses: Web Conference, Screencast recording, Podcasts, lectures, and interviews.
The Polsen RC77u was designed with the “retro look” down to the last detail, including the artwork on the box. In that respect, the company also sought to deliver a sound consistent with old-timey microphones from about the 1940s to the 1960s. The old fashioned sound of its analog counterparts could be defined as “smooth and natural top end, mid‑range clarity and low‑end warmth.” 2 Does the Polsen RC77u Deliver?
Let’s hear the Polsen RC77u:
Pros: The RC77u is plug and play, has minimum acceptable bit depth and sample rates, is Windows/Mac compatible, and has Zero Latency monitoring for Mac and PC. The look and design are truly classic looking, and it features a tactile volume control for headphone monitoring.
Additionally, the Polsen RC77u comes with a lightweight metal stand and a cloth carry bag for scratchless carry in your backpack or purse, and is stand mountable to any standard threaded microphone stand.
Cons: According to the Polsen Audio website the Polsen RC77u has “an integrated dual-stage grille (which) minimizes pops and vocal plosives.” Unfortunately, our testing has proved otherwise. That does not make this a bad microphone, it only means that users with powerful voices would do well to sit back a few inches, and employ a pop-filter. We also experienced some slight latency monitoring using Adobe Audition in the Multitrack editor mode. Otherwise, latency was not noticed.
Uses: Screencast recording, podcasts, and lectures.
I saved the Shure MV5 for last, because it offers some unique features above and beyond our five point checklist. For starters, the MV5 comes with a lightning adapter cable, allowing users to plug into an iPad or iPhone. This mobile utility does require an app, but is free and quick to install. Files can be sent or shared from the device and are otherwise identical to their standard computer counterparts. The mobile app has features and audio effects for limiting, compression, and equalization on-the-go. However, I recommend sending the file to your computer and processing those effects using professional software.
Let’s hear the MV5 in all three of its modes:
- Flat Response Mode
- Voice Mode
- Instrument Mode
Pros: The Shure MV5 offers three mode settings for flat response, voice, and instrument, which are manufacturer presets designed for non-audio professionals looking to streamline their recording experience. For our purposes, it’s an excellent feature. (Audio professionals may consider this a drawback, but I think it’s one we can live with.) The vocal setting is tuned to brighten up frequencies in the vocal range, which to the untrained ear presents as having your voice sound louder than normal. And for the powerful vocal user, the instrument setting serves as a pad, to soften the blow of loudness.
Cons: While the unit has a tactile volume control for monitoring, it’s kind of tough to reach and does not boost all that high without aid from your computer’s volume controls. The Shure MV5 also comes with a really short mounting stand and a non-standard mount known as ¼-20 thread. Quarter twenty thread is the standard for camera stands, which means you can mount the microphone head to a camera tripod, which would be weird, unless it’s a cellphone tripod (still weird.) But you can purchase ¼ -20 adapters for standard mic stand mounts, and they are not cost prohibitive.
Uses: Web conference, screencast recording, podcasts, lectures, and interviews.
Go Mic Connect
|Sample Rate, Bit Depth||44.1/48 kHz
|Polar Patterns||Omni Directional, Cardioid, -10 db||Omni Directional*||Cardioid||Cardioid||Cardioid|
|Notes||Multipurpose mic on-the-go, built in -10 db noise reduction option.||See Conclusion notes.||Excellent multipurpose mic.||A good mic with a retro design. Exhibits some frequency response issues with plosive syllables and sibilance.||Features a lightning cable adapter for users to record on-the-go to iPad, iPhone.|
Of the five mics tested and compared, the Samson Go Mic and Samson Meteor are the runaway heroes for faculty in Distance Learning. Both models are durable, excellent sounding, and multipurpose microphones, at a fair price. The Go Mic offers a bit more flexibility in its capacity to travel, excellent carioid pick-up as well as an omnidirectional for recording multiple voices from all directions. The Meteor offers professional quality range and results at a consumer price. Both are excellent for hosting web conferences and for various types of content recording.
I purchased my personal Go Mic for $34 on Amazon. Prices can fluctuate often due to holidays, sales, and other market conditions so keep an eye out for good deals. The Meteor Mic I own I bought for $25 at a pawn shop, negotiated down from $40. Meteor mics in excellent condition are readily available on Craigslist and eBay for less than retail price.
The Shure MV5 offers features not offered on the other four mics including on-the-go adapters for mobile devices and pre-tuned recording modes for non-audio professionals. It’s mode presets make it an excellent choice for users with loud impactful voices. Also an excellent choice for Distance Learning faculty if you are willing to spend higher dollars.
The Polsen RC77u is a capable microphone for certain uses and appeals to a unique audience of audiophile if you don’t mind spending a few extra dollars. In the opinion of this reviewer, the RC77u definitely delivers in the low end warmth, but fails in high end brightness and mid range clarity, performing poorly with sibilance. Not a bad microphone, just not retro sounding.
Unfortunately, the Samson Go Mic Connect creates more questions than it answers for average audio consumers as well as audio professionals. This mic exhibits latency issues for Mac, but not for PC. It requires a software installation to maximize performance, but one that differs slightly on Mac and PC, creating a mismatch in results across the two systems. The proprietary software does include a beam-forming technology to reduce feedback and ambient noise. What was supposed to be an upgrade to the technology of the Go Mic ended up as a design and delivery disaster.
- Romano, F. (Dec 16, 2012) The history of frame rates; why speeds vary. Vanillavideo.com Retreived June 16, 2017 from https://van illavideo.com/blog/2012/history-frame-rates-why-speeds-vary
- Robjohns, H. (Jan 2011) What are the characteristics of vintage mics? Sound on Sound. Retrieved on June 20, 2017 from http://www.soundonsound.com/sound-advice/q-what-are-characteristics-vintage-mics
- Microphones: Polar Patterns & Directionality. Shure. Retreived on June 23, 2016 from http://www.shure.eu/support_download/educational_content/microphones-basics/microphone_polar_patterns
- Coppinger, R. (10/24/2013) 7 Effective Techniques for Minimizing Plosives. Pro Audio Files. Retrieved on June 23, 2017 from https://theproaudiofiles.com/plosives/