SOAS University of London

The Zoom H2 Audio Recorder

Bernard Howard and Stuart McGill, SOAS

Figure 1: Zoom H2: front view.

Bernard Howard is an audiovisual technician. He tested the H2 in the UK, mainly by recording music.

Stuart McGill is a post-doctoral researcher and used the H2 as his sole audio recorder on a recent three-month field trip to Nigeria. He mainly recorded speech.

Physical description

The Zoom H2 is a compact and lightweight digital stereo/4channel recorder. At 110mm x 63mm x 32mm, it fits easily into a jacket/shirt pocket. The H2 comes with two stand accessories: one allows it to stand on a flat surface, while the other provides mounting in a regular microphone clip or can be held in the hand to reduce handling noise. Both accessories screw into the threaded hole on the H2’s base, which is the same as those on cameras and therefore allowing use of a normal tripod or other camera stand, a bonus for the field recordist (see Figure 4).

Additionally you get a soft carrying bag, a foam wind shield, USB cable, earphones, minijack to phono cable, a mains power supply unit and a 512Mb SD card, although you will want to use a larger capacity SD card for any serious recording work.

Display and controls

We found the H2 mostly easy to use and intuitive, apart from the main recording controls (see ‘Recording and recording options’ below). The controls provide quick access to all of its functions and all buttons and sockets are clearly labelled.

Figure 2: The Zoom H2's display and controls.

On the front there are seven buttons, an array of six LEDs, and a small LCD screen. The buttons control record/playback, and provide access to the menus. The LEDs indicate microphone activity, microphone mode, record and playback mode. The LED screen - which at 25mm x 15mm is quite small and hard to read - displays current menu settings and audio levels in both 2 and 4 channel mode.

The left side has an external power socket, the on/off switch, playback/monitoring volume, and a 3.5mm headphone/lineout socket. On the right is a USB socket, a 3.5mm line-in socket, a 3 position microphone gain (sensitivity) switch, and the 3.5mm external stereo microphone socket.

On the rear of the unit is one additional LED which indicates microphone activity for one of the microphone modes (see ‘Microphones’ below).


The H2 has the a fairly standard set of sockets for a miniature recorder: 3.5mm stereo mic-in, 3.5mm stereo line-in, line/headphone out, and mini USB.

Figure 3: Right side, showing input sockets, mic gain control, and USB connection.

The H2 lacks its bigger brother's XLR and phono sockets (see H4n review). However, some people are sure to be attracted by the quality of its built-in microphones to not using an external microphone at all. In fact, the H2 is so much in the small/light category that many will choose it for these portability reasons and will not wish to carry additional microphones and the corresponding XLR cables.

Nevertheless, the recording capabilities of the H2 are considerable - not very distinguishable from its bigger brother, the H4n (see review) - so that it does make a good companion for a range of high quality microphones, only requiring an XLR to minijack adaptor or converter cable. See ‘Doing away with external microphones’ below for more discussion of the pros and cons of using the built-in microphones.

Usefully, the USB socket can be used to power the H2 from a computer or other USB-fed power source. It also allows the H2 to be used as an audio interface for a computer, effectively functioning as an external sound card to enable digital capture of audio from devices such as cassette players.


The H2 has four internal microphones, and is capable of making two- or four-channel recordings. The microphones are of quite high quality, especially in relation to the price and size of the unit, giving an accurate and uncoloured response. These microphones can be configured in four ways:

front 90 degrees, 2 channel stereo
front and rear, 2 channel stereo surround
front and rear, 4 channel stereo surround
rear, 120 degrees, two channel stereo

The external stereo microphone socket provides the fifth, and, for most documentation purposes, the best microphone option. A Sony ECM-MS957 stereo microphone gave good results. If a mono external microphone is used, the H2 records the left channel only.

Recording level is adjustable (with 127 degrees of sensitivity) simply using two buttons on the front face. To cater for microphones of varying sensitivities, the H2 has 3 input gain settings (see Figure 3).

Recording and recording options

Recording can be confusing, mainly because too many functions have been squeezed onto just two buttons, ‘Record’ (the button with the big red spot in Figure 2) and ‘Play/pause’ (which sits below ‘Record’). These buttons have multiple and counter-intuitive uses. Slightly confusing, at least at first, is that a single press of the ‘Record’ button does not start recording. Instead it puts the H2 into the ‘record standby’ mode (shown by the PLAY/REC indicator flashing red). While this is useful because it allows you to first monitor the background noise and make any necessary adjustments before starting the recording, it would be less confusing to have a separate control rather than overburdening the ‘Record’ button. To start recording, the same button needs to be pressed again (at this point the indicator light glows red continuously). However, more seriously confusing is that the same red button is used yet again to stop recording; the third press of ‘Record’ stops recording altogether. We found it slightly irritating that it was easy to put the H2 on standby and forget to start recording; but, more alarmingly it was all too easy to unintentionally stop recording by accidentally pressing the record button again. Perhaps to counter this vulnerability, the menu button can function as a lock; if it is pressed for 5 seconds once the machine is recording, the record mode is locked and a message appears on the LCD screen (unlocking is by pressing the menu button again for five seconds).

Another disadvantage of not having a dedicated ‘Stop’ button is that the ‘Play/Pause’ button is also over-used. So if you place the H2 in ‘record standby’ and decide not to record, after all, you have to press the ‘Play/Pause’ button - which is not at all intuitive. Similarly, if you have already started recording and then press ‘Play/pause’, the H2 does not, as you might expect, pause; instead it adds a mark (a “cue point”). Again, this is a useful function, but in an unexpected place. In short, if the unit’s designers had added just one extra button for ‘Stop/Cancel’, a lot of confusion could have been avoided.

The H2 can make mono, 2 channel or 4 channel recordings. The mono setting uses the same amount of memory as a stereo recording. A four channel recording uses twice as much as a stereo recording. Bear in mind though that to get the benefit of recording in 4 channels you will need a surround-sound system for playing back. Unless the event you are recording is particularly complicated spatially, 2-channel stereo should be sufficient (and even if there are sounds emanating from many directions it is unlikely that the H2’s fixed configuration will be optimal for capturing them).

The H2 can make recordings in WAV format with resolutions ranging from 44.1kHz 16 bit up to 96kHz 24bit. It can also record in MP3 format, although this will be of limited use to language documenters since compressed formats are not recommended for serious linguistic work. More useful is the H2’s ability to convert its WAV recordings to MP3. This means you can make a recording in WAV, convert it to MP3, and then easily transfer the MP3 file via SD card or USB to other devices (e.g. mobile phone, MP3 player) in order to conveniently share the audio - and all this without needing a computer. MP3s would be useful, for example, for distributing audio to several people who are collaborating in transcription, or for emailing as emergency backups.

Other options are:

  • AGC (automatic gain control). This should definitely be avoided; it responds too slowly, and is generally an inappropriate option for voice recording (“gaps of silence” between parts of an utterance will be artificially “pumped up” by the gain mechanism which will only result in amplifying any unwanted background noises).
  • Low cut, which is useful in reducing wind noise when recording outdoors.
  • Plug-in Power, for microphones without their own power source.
  • Pre-Record. When on record standby, this option retains about 3 seconds of sound that occurred before the record button is pressed again to start the recording. This function could be useful to avoid missing the opening words of a speech event.
  • Auto-record. This function starts recording when the audio level exceeds a certain (settable) value and stops recording when the audio level falls lower than a (settable) stop level (this function might be useful for surveillance work).

The H2’s inbuilt microphones are not as sensitive to wind noise as, for example, the Sony PCM-D50 which we previously found almost unusable without its foam windshield. The H2’s supplied wind shield performed better than expected, doing a fairly good job of avoiding distortion even when recording in the Nigerian harmattan breeze. However for stronger breezes or wind an external microphone with a high quality fur-type windshield will be necessary.

Doing without an external microphone

The H2’s high-quality internal microphones make it feasible to use this recorder for language documentation without an external microphone. This is also true of the Zoom H4.

Figure 4: The bottom of the H2, showing its camera-compatible mounting thread.

Recorders with inbuilt microphones have several advantages for the language documenter, the most obvious of which are lower cost, size and weight. Another benefit comes from the simplicity of only having one physical object to worry about - with an external microphone even apparently trivial tasks such as where to place the equipment and connecting cables can cause problems in the case of unfamiliar (or uncontrolled) locations or speech events. Transportation, maintenance, pre-recording checking, and placement all become more complicated and make the language documenter less flexible. This is particularly true when the fieldworker is working on his or her own, or when they are required to respond quickly to unexpected events. A stand-alone recorder such as the H2 avoids these difficulties, and is therefore much more flexible. For example, using the supplied screw-on hand-held pole (holding the H2 itself will create too much handling noise) fieldworkers can easily record impromptu high quality “journalistic” interviews.

Nevertheless, doing away with an external microphone introduces other problems that are perhaps less obvious. The main problem is that by using such a stand-alone mic/recorder, it is no longer possible to physically interact with the recorder without interfering with the recording process itself. So, for example, if you are recording a song or conversation and you decide you want to adjust the recording level, this cannot be done in a non-intrusive way. Firstly, you have to physically touch the H2 which will result in handling noise. Secondly, you have move quite close to the unit in order to see the controls well enough to make adjustments, which is likely to be intrusive or disruptive to the event you are attempting to record. On the H2, and many other similar recorders (H4n, Edirol R-09 and others), even just a simple check of the recording indicator LED or record levels becomes an intrusive act, because they will be facing the speaker, not the fieldworker. And this problem is exacerbated when using the H2 because, due to its counter-intuitive controls (see ‘Recording and recording options’ above) the fieldworker may feel the need to check the LED status more often than with other recorders.

To sum up: while it is good news for language documenters to see a stand-alone audio recorder with good quality microphones and recording capabilities at an affordable price, there are practical and methodological disadvantages to using its internal microphones, most notably for language documentation fieldwork. It is recommended that you also obtain a suitable microphone, which is likely to improve the quality of your recordings.


Figure 5: SD card and cover at bottom front of unit. This cover is prone to breaking.

The H2 uses SD or SDHC memory cards. The specifications and online information at time of writing (both official and unofficial) are unclear about the extent of the H2’s support of SDHC and of cards with greater capacity than the SD maximum of 4GB. However, for most documenters, it is preferable to use cards of 4GB or less (while they remain available). Since these are sufficient to hold about 4 hours of 48kHz 24 bit recordings, and their cost has dropped to around US$2 per hour of audio (which is comparable to what we paid for minidisks/DATs/cassettes in former days) documenters are now recommended to lock cards against writing and keep them as an additional layer of backup for all field recordings.

The memory card slot is on the bottom front of the H2 and has a hinged plastic flap over it. Like the battery flap this is weak, and in fact the one on Stuart’s H2 broke after less than a week of use. The unit can still be used, but there is more risk of malfunction through dust entering.

Playback and transcription

This is one area where the H2 falls down a little. Although its fast forward/rewind buttons are easy to control, the H2, unlike other audio recorders (e.g. Marantz PMD 660/671) does not allow you to add ‘marks’ (or ‘cue points’) while listening back. These marks let you easily replay sections of a recording over and over again to help in the process of transcription. With the H2 marks can be added during the recording process, but this is of more use for delimiting particular speech events (e.g. the end of a song) rather than as a transcription aid.

Another problem is that the H2 has no built-in speakers. This means that it is not possible to immediately play back what you have just recorded to more than one speaker at once - a slight drawback for fieldwork, especially in more remote areas of the world. It may also pose a problem when transcribing. If you do not need help to transcribe you can use closed headphones connected via the H2’s line/headphone out socket. However if two people need to listen you will need to either get some portable speakers, or alternatively copy the recording to another device which does have speakers (in which case the H2’s MP3 conversion function mentioned above will come in useful).

Figure 6: The H2 battery compartment and cover. The cover is easy to break and/or lose.

Batteries and power

The H2 runs on two AA alkaline or NiMh rechargeable batteries. This is a definite advantage for those working in more remote areas, since AA batteries are available in most parts of most countries. The battery compartment lid has flimsy locating tongues, and on one of the H2s accessible to us some had already (been) broken off.

To test the unit's battery life, we used two new Duracell (alkaline) batteries. The H2 was able to record for about 4.5 hours before a low battery message appeared on the display. Two freshly charged NiMH 2500 mAH batteries gave only a slightly less time of 4 hours of recording.

Once the low battery message appears, the H2 will stop recording after a few seconds, save its settings and data, and then shut itself down. This low battery shut down system worked reliably in the field, although it occurred infrequently due to the long battery life. However, the H2 is less forgiving when using its mains power unit, as the current recording may be lost if the power is disconnected before a recording is saved and the unit properly turned off.


The H2 is versatile and extremely good value for money. We were able to make good quality recordings in the lab and in the field. It is quick and easy to set up, and the internal microphones are of excellent quality for a unit of its size and cost.

Summary of positives:

  • small size
  • light weight
  • quality of the internal microphones
  • the AA batteries are easily obtainable
  • reasonable price


  • counter-intuitive recording controls
  • hard-to-read screen
  • flimsy card and battery covers

It is understandable that compromises had to be made to design a unit as small and cheap as the H2. If we could be granted just one wish for improvement it would be to add one or two extra buttons to make the controls a bit more intuitive (e.g. a ‘Stop/Cancel’ button).

Taking all factors into account, we preferred the H2 to its bigger brother the Zoom H4n. The H2 offers similar options, and even recording quality, but is much cheaper, smaller and lighter. Its main deficiency is that it lacks XLR and quarter-inch input sockets that provide connection for professional-grade microphones and cables.

At a price of about £160 (Amazon UK), the H2 is probably the best value-for-money digital recorder. Despite its idiosyncratic controls, it is especially good for the field researcher who has to travel light. We preferred it to the Edirol R-09 (£250 from Amazon UK) not only due to the H2’s lower price, but also we felt the H2’s internal microphones are superior. We also preferred it to the Olympus LS-10 (£226, which offers similar functions to the H2 but did not perform as well with external microphones.

As an affordable high-quality stand-alone audio recorder the H2 has the potential to transform language documentation in poorer parts of the world. For example, a Nigerian linguistics department was recently able to buy twenty Zoom H2s for students to use on fieldwork - this would have been impossible only a few years ago. The low price also makes it more feasible for individual researchers to own one, particularly as students may have other applications for it (e.g. recording lectures). Perhaps the highest praise we can give to the Zoom H2 is to say that both reviewers have now bought one for themselves!


For more information, see

May 2010