Microphones For Portable Recorders 3: How To Choose?

Updated July 2024 for clarity and to remove anachronisms. Prices updated.

This is the third in a series of articles on choosing external microphones for portable digital recorders. Part one discussed why we might not wish to use the built-in mics on our recorder and part two was an overview of microphone types plus power and cabling requirements.

Now is the time to fix your objectives in mind. Are you recording lectures or community meetings? Are you gathering dialogue for a video? Are you conducting interviews in the street? Are you recording live concerts or your own band in rehearsal? Are you making nature or soundscape recordings?

I will discuss each use case and recommend microphone types (dynamic, condenser, electret, boundary), polar patterns (omni, cardioid, shotgun), and power requirements. Specific tried-and-true microphone models will be mentioned as a starting point.

Context and disclaimers

One big disclaimer. There are hundreds of brands and thousands of makes of microphones on the market. I have used only a fraction of these, and have worked extensively with even fewer. Though I will mention specific models, there are plenty of other valid choices that will work just as well for the given application.

Another thing to keep in mind is that I am primarily concerned with field recording. To my mind, that's why we use a small portable recorder. If you have the luxury of a studio space or a concert hall, you will also have access to bulkier and more expensive gear. So I will ignore studio equipment in this primer and won't recommend ribbon mics, large-diameter condensers, and so on. This is not to say that you absolutely cannot use such equipment in the field, but generally there are more practical choices. Especially for the beginner.

Finally: price. You can buy a high quality portable recorder for 200 bucks¹, something that is far better than anything we hoped to use back in the day. Some people are understandably shocked when recommended microphones that much more. But good microphones cost money and small increments in improved sound quality cost disproportionately more money to achieve. That extra 5% improvement might double the cost. So be realistic about the quality you need to achieve. And set a budget that is sufficient to the task. (Prices below are from Thomann and CVP.)

Like everyone else, I enjoy finding gear that performs better than it should for the price. I don't own any of the truly expensive microphones that top-flight professionals have in their kit bag. As someone who has spent many years as a "starving artist", I sympathise with people on a modest budget. But sometimes you simply do need to save for better equipment. Or, re-align your priorities.

If you know a little electronics you can sometimes create your own solutions at a fraction of market price. Unfortunately my own electronic skills are minimal, limited to soldering cables and making contact mics. 

OK, with all of that in mind, let's have a look at each recording task.

Lectures or community meetings

In this situation you might well be seated far away from your source but you can't use a fancy setup that will intrude on the presentation. If you've tried recorded a lecture from the other side of a classroom, or a political meeting from the back of a hall, you realise soon enough that reverberation and crowd noise easily drowns out the speaker. This might be good enough for transcription, but won't be good enough to share playback (for broadcast or other purpose). So your goal is to get the mic close to the speaker: on a table, on the podium, etc. 

Get the appropriate permission ahead of time, set your recorder and use the built-in mics. Don't forget to retrieve your recorder after the event!

You likely only need to record in mono. This can save storage space and battery power.

If you do need improved sound quality, a boundary microphone can work well. These are common fixtures in board rooms, churches, and so on. Crown and Shure are the most common makes.

A completely different approach, one that might require more cooperation from the speaker, is to use a lavalier. Read on...

Dialogue for video

Entire books have been written about recording sound for video and film. There are also dedicated websites like DV Info. My own gloss will cover two methods: using a boom mic or lavalier.

Boom mic

Mount a shotgun microphone on a boom, a telescoping pole which enables you to hold the mic over the action. An experienced operator can exclude undesirable sounds from off-axis. Recall that a shotgun pattern has a considerable rear lobe (and smaller side lobes), so one must point the microphone directly at the source while avoiding distracting sounds from the other axes. Generally this is accomplished by angling the mic down from above.

A classic short shotgun is the Sennheiser ME66 paired with the K6 power module (pictured above). You might still find this for rent, but it appears to be discontinued. An alternative is the Rode NTG2 (€260 or €295 with a "dead cat" wind suppressor). These models run off their own batteries and so don't require power from the recorder. Add in the price for the Rode boom pole (€115) plus the necessary cables and interconnects. You might be able to find a good bundle deal. 

Professionals might use the Sennheiser MKH 416 (€750), Sennheiser MKH 8070 (€1550), Sanken CS-1E (€1020), or Sanken CS-3E (€1860). Don't say I didn't warn you about prices!

Carrying a boom rig mandates a strong physical presence that may not be suitable for all recordings. 

Lavalier

The second method involves putting a lavalier mic directly on the subject, either in plain sight, hidden under clothing, hung around the neck, etc. These small condenser microphones are often available in different colours (white, black, flesh) to aid in camouflaging their presence. A good lavalier will resist noise from clothing and other sources. They are omni or cardioid in pattern.

If the subject needs to be mobile, it is common to run a lavalier to a radio frequency transmitter pack on their belt. This links up to a receiver at the recorder, eliminating the need for direct cabling. This solution might require a significant investment.

Professionals use lavs by Audio-Technica, Countryman, Sony, Tram, and several other firms, with prices around €400-600. A cheaper solution is the Shure WL183 is €180. Don't forget the mounting accessories.

Each brand seems to have come up with their own proprietary cabling and power systems. It's an art matching microphone capsules, cabling, interfaces, transmitters, and power sources. (To simplify, buy a full kit from one manufacturer.)

Interviews and ENG

ENG (Electronic News Gathering) is one of the more popular applications for portable recorders. Journalists require a microphone that is able to stand up to the rigours of the street, withstand inclement weather, reject plosives, and avoid handling noise. Low self-noise is not a priority in a loud environment, especially considering that the mic will be directly in the subject's face. You don't want to be messing around with different power systems. Dynamic microphones fit the bill perfectly.

Be aware that dynamic mics have low sensitivity and so need more gain to reach a decent signal strength. Unfortunately smaller recorders are often shy on gain, so try to get the "hottest" possible mic. Favoured omnidirectional dynamic microphones include the Electrovoice RE50/B (€280) and Sennheiser MD-42 (€200). 

The Sennheiser MD-46 (€240) is a cardioid version of the MD-42. This pick-up pattern will require slightly more care in use, but will capture less of the environmental sound. Consider how much control you will have over the interview situation, and if it is indeed desirable to get some environmental sounds for context. You might very well want an omni and a cardioid, so you have the flexibility to use the right mic for the situation.

You can find more advice at Transom, a site focused on the radio community. Though quite often I disagree with their recommendations. 

Music concerts

Amplified gigs are loud, so the number one concern is not overloading your pre-amps or mic capsules. You need a mic with the ability to handle high sound pressure level (SPL) without distorting. Even though acts might well permit concert taping, it often pays to be discreet. Small mics that can be hidden under a hat, on glasses, or disguised as headphones are often just the ticket. Concert tapers often use a stereo pair of electret condensers, sometimes incorrectly called binaurals².

While there is no technical difference between these mics and the lavaliers discussed above, the application is quite different. A mono lav with proprietary power system and transmitter is quite a different setup from a stereo electret pair working off standard PIP. An interview lav should reproduce the human voice, accurately capturing resonances and inflections. If it rolls off the lower frequencies, so much the better, since these are not necessary. But if you are recording a rock gig, the last thing you want to do is roll off the bass!

Pictured above are a pair of electrets, clipped on a baseball cap. This can be worn with the recorder in a pocket, safely out of the way. It won't bring much attention or get in the way of the enjoyment of other punters. This same setup is useful for candid street recordings. Though you can get away with an all-purpose set of mics, recordists with a larger budget might have one set of low sensitivity mics for concerts, plus one set of high sensitivity, for quieter locations.

Discussing which electrets to buy is complicated enough to reserve for another article. You can buy a pair of capsules for €10 and solder a set. Or you can purchase a pair of DPA 4060 for €900 and run them off phantom power. The good folk at Tapers' Section can help you spend your money.

Nature or soundscape recordings

This is a huge subject area as it incorporates divergent recording objectives. What they have in common is a desire for the lowest possible background noise. We need microphones with a low self-noise specification and high efficiency. Furthermore we must pair these with a good pre-amp and use the very best recording techniques.

Nature recordists often want to isolate a particular sound (a bird call, for example) from the environment, making it as loud and clear as possible. This means a) getting the microphone very close to the animal, b) using a shotgun microphone, or c) using a parabolic reflector to focus sound from a distance. In the first case almost any mic will do, though you might prefer a dynamic for their robust build. The trick then is in the positioning and having the patience to wait. Shotgun microphones have already been discussed. Parabolic reflectors are specialised enough that simply mentioning them is enough for this primer!

Soundscape recordists, on the other hand, usually wish to replicate the entire sonic environment, rather than focus on one specific sound. Since omni-directional microphones are the quietest, the most resistant to wind noise, and colour the sound the least, these are the ideal choice. Various creative techniques involving "dummy heads", Jecklin disks, or boundary layers can be used to further enhance the recording, sculpting it to conform to how we hear. 

Unfortunately, answering the question of "which microphone?" becomes complicated. You might wish to continue reading my comments on field recording gear and my PIP Microphone tests. 

Conclusion

I trust that this series introduces you to the world of microphones. Armed with a basic understanding of microphone terminology, a strong idea of your objectives, knowledge of the abilities and limitations of your recorder, and a budget, you should be able to make headway in the confusing profusion of information out there on the web.

Footnotes

¹ A "buck" is a standard monetary measure approximately equal to one American Dollar, British Pound Sterling or Euro. Because generally, more or less, most of the time, give or take 20%, one unit of measure in either of these buys the same audio gear.

² The term "binaural" actually defines the recording and reproduction methods, not the microphones themselves.

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