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Fostex FR-2LE Review (for linguists)
Even early on, there was little doubt that solid state (flash memory) storage would be preferable to magnetic tape (DAT) or optical disc (Sony MiniDisc, CD-R, DVD-R). Recently, several digital field recorders appeared on the market. You can find a nice review of those at transom.org. Also, do make sure to visit the Vermont Folklife Center's very informative review of audio equipment for field use. However, while many of the digital obstacles have been overcome, the same old problems of acoustic and electronic performance, battery life, professional microphone interface, high build quality, etc. have prevailed. Several of the major manufacturers (Edirol, Sony, Tascam, M-Audio, Olympus) have focused on designing small devices with built-in stereo microphones for recording ambient sounds, including lectures, podcasts, live shows, sounds of nature, etc. Such devices, however, often do not meet the needs of a field linguist. The notable exceptions include the recorders designed for the motion picture industry and electronic news gathering: Sound Devices 700 Series (702, 722, 744), Fostex FR-2, Tascam HD-P2.
The FR-2LE - what I like a lotRich feature set in a compact form factorFor most of my field recording needs, I have typically preferred to use a recorder with an external microphone pre-amplifier (e.g., the Sound Devices MixPre). I just was never happy with the quality of the microphone pre-amplifiers on most stand-alone recorders (see my review of the Marantz PMD660, for example). The FR-2LE is the first affordable (under $1,000) field recorder I have tested that virtually eliminates the need for the MixPre. Indeed, I am confident that the FR-2LE is going to meet most of my field recording needs as a fully stand-alone device. For me, this is a little bit of a breakthrough. I used to use the Tascam DAT recorder (DA-P1) by itself, but the atrocious battery life and hissy pre-amplifiers always bugged me. Click here for detailed specifications of the Fostex FR-2LE. Professional analog interfaceThe FR-2LE has two combo microphone (balanced XLR) and line (unbalanced 1/4-inch TRS) inputs. Additionally, the microphone inputs can be supplied with on-board phantom power. The interface uses industry standard impedance and levels. This guarantees that you should be able to use a wide variety of professional-grade dynamic and condenser microphones, as well as interface the recorder with line level devices, such as stand-alone microphone pre-amplifiers, field mixers, mixing consoles, etc. High quality microphone pre-amplifiersThe pre-amplifiers have high gain and low noise. They will adequately drive my Sennheiser HDM25 dynamic microphone, as well as my Beyerdynamic Opus 55 MK II condenser. The noise floor is very good, the gain clean, virtually free of distortion even at the maximum setting. High quality phantom powerThe phantom power supply works great. That's really rare on devices of this type. It drives my condenser mics really, really well. Long battery lifeThe FR-2LE uses four standard AA batteries, either rechargeable or Alkaline. It offers about 8 hours of field use, which is at least twice as much as any of the devices I've used so far. You should be able to find AA batteries even in the world's most remote areas, which is of crucial importance to field linguists. You can conserve power by not using onboard phantom power supply and the headphone amplifier. However, try to get the highest capacity batteries you can find, set the correct battery type in the recorder's setup, and always keep your batteries freshly charged, with spares handy. For even longer battery operation, consider one of the field power distribution systems available from pro audio retailers. Also, Fostex recommends using a high-capacity battery (Tamiya RC3600HV), but I had trouble finding one in the US for a decent price. The battery compartment may seem a bit odd at first because you have to load the batteries to a plastic holder first, and then insert the holder into the battery compartment. Once you figure out how it works, it is easy and dependable. 24-bit PCM audio filesThe FR-2LE records 24-bit uncompressed PCM audio files in the Broadcast Wave Format, which is a version of the WAVE file format that has arguably the most archivally stable specification, primarily due to its use of meta data chunks. The sample rate can go as high as 96 kHz, but I typically record speech at 48 kHz. The FR-2LE make very clean audio files. It is a pleasure to listen to the recordings. The sound has exceeded my expectations. Bear in mind, this is a $600 device, so you should set your expectations accordingly. There are many similarly priced devices that don't deliver such high quality A/D conversion. Standard Compact Flash mediaThe FR-2LE uses the standard Compact Flash specification. It comes with a 1 GB card, but you can use any of the major CF cards by SanDisk, Lexar, etc. Click here for a list of supported CF cards. Important note: the recorder formats each card for a particular recording format and you cannot change the format without re-formatting the card. This is done for data stability and security. I use two different card sets: one for 24-bit/48,000 Hz stereo (for interviews) and one for mono (for individual elicitations). I recommend that you choose a similar strategy. Easy operationThe FR-2LE is very easy to use. The menus are simple and logical, the buttons sufficiently large. It comes with a very cute remote controller, as well. The LCD can be lit for operation in the dark. The display is clear and responsive. Real-time levelsThe FR-2LE has real-time LED levels indicators as well as a very responsive levels display on the LCD. This makes calibration and levels control very easy. Level LEDs are missing on most field recorders. Signal processingThe FR-2LE has an automatic levels control (ALC), a high-pass filter, and a limiter on board. They work reliably, at least as well as my MixPre. Great! I hardly every use ALC but the limiter and high-pass filter are often very useful in the field. Note that the processing is strictly in the digital domain so it is not as robust and effective as analog high-pass filter and limiter found on higher quality equipment, such as that by Sound Devices. Still, the processing is effective, and it is there for you to use, should the need arise. Audio testsI have chosen to use two completely different types of microphones to test the Fostex FR-2LE with. Each microphone poses a different set of challenges to the recorder. The degree to which the recorder can handle both microphones will be indicative of the recorder's ability to provide adequate acoustic and electronic performance for a wide variety of microphones that can be used in the field. Because most of us record speech at normal conversational levels, the pre-amplifier gain typically needs to be set quite a bit higher than when recording singing or live musical events. Unfortunately, very few of the budget field recorders are made with that in mind. Most of them are designed for ambient sound recording, inlcuding band practices, live shows, etc. I recommend that you always judge the quality of the field recorder by the quality of its pre-amplifiers. The Fostex FR-LE2 stands out in the under $600 category as having respeactable microphone pre-amplifiers. Sennheiser HMD25The Sennheiser HMD25 is a professional, dynamic headset microphone that is ideal for recording speech in noisy environments. Being a dynamic microphone, the HMD25 requires a pre-amplifier with low noise and high gain. It is problematic for many field recorders, but the Fostex FR-2LE handles the microphone really well. Figure 1 shows a spectrogram of a Polish phrase "Czarna krowa" recorded at approximately -12 dBFS (a reasonably high level). You can see very good spectral detail with very little noise, and virtually no distortion. DOWNLOAD ORIGINAL FILE.
Figure 1. Spectrogram of a phrase "Czarna krowa" with the Sennheiser HMD25 microphone Similarly, a narrow-band FFT spectrum of the vowel /a/ in "czarna" (Figure 2) shows a very natural spectral envelope and sharply defined formant peaks.
Beyerdynamic Opus 55 Mk IIThe Beyerdynamic Opus 55 Mk II is my microphone of choice for the most demanding recording applications. The microphone has a highly flat and wide frequency response, as well as medium sensitivity, which allows it to record really high spectral detail and achieve very favorable signal-to-noise ration (SNR) with close placement. Being a condenser microphone, the Beyerdynamic Opus 55 Mk II requires phantom power supply of 48 V. It is rather uncommon to have a reliable, quality phantom power supply on a portable filed recorder, but the Fostex FR-2LE handles the Beyerdynamic Opus 55 Mk II without much effort. Figure 3 shows a spectrogram of a Polish phrase "Czarna krowa" recorded at approximately -12 dBFS (a reasonably high level). You can see very good spectral detail with very little noise, and virtually no distortion. DOWNLOAD ORIGINAL FILE.
Figure 3. Spectrogram of a phrase "Czarna krowa" with the Beyerdynamic Opus 55 Mk II microphone Similarly, a narrow-band FFT spectrum of the vowel /a/ in "czarna" (Figure 4) shows a very natural spectral envelope and sharply defined formant peaks.
Figure 4. FFT of the vowel /a/ with the Sennheiser HMD25 microphone Real-world noise performanceIt is unreasonable to expect lab/studio noise performance from a field recorder. However, the Fostex FR-2LE really surprised me with excellent noise performance, especially for a recorder in this price bracket. I encourage you to read my post about noise testing. It explains how theoretical and real-world noise measures are derived, tested, and intepreted. The Fostex FR-LE2 EIN value is -129 dBu. Fostex actually does not publish the EIN value, but it was independently measured by the Avisoft Lab. By definition, the recorder is going to perform really well with most condenser microphones. It turned out to be the case in my experience. You can download the audio files at the bottom of this page for your own perusal. However, I was really surprised just how well the Fostex FR-2LE performed with a dynamic microphone. The Sennheiser HMD25-1 is my dynamic microphone of choice for recording speech in noisy environments. Being a dynamic microphone, it has the typically low sensitivity of 1 mV/Pa and it naturally requires higher pre-amplifier gain than most condenser microphones. Figure 5 shows a spectrum of the HMD25-1 and FR-2LE sefl-noise print. The overall level and distribution of the noise are surprisingly good.
Figure 5. A spectrum of the noise print generated by the Fostex FR-2LE recorder and the Sennheiser HMD25-1 microphone Fostex FR-2LE - what's missingLet us now look at some of the features that are missing on the FR-2LE. I believe that most of these features are essential only to professional video and audio production and will not be too badly missed by field linguists. TimecodeFostex has been a provider of professional-grade recording equipment for several decades. They have a strong focus on location recording, broadcasting, and live recording. The FR-2LE appears to be the little brother of the FR-2, a professional timecode portable digital recorder. The timecode function is extremely useful for synchronizing audio and video feeds, but has less importance for straightforward audio recording. So if you plan to record audio and video footage simultaneously, you may have to buy the FR-2. Otherwise, the lack of timecode functionality should not be a deal breaker for most field workers. Digital input and outputThe FR-2LE does not have a professional digital input and output option. Such capability enables recordists to route digital audio data (using the AES/EBU interface) directly into and out of the recorder in real time. This only makes sense if you have a number of other devices in your recording circuit and use the recorder itself as digital storage and/or a router device. I assume that most field linguists would much rather avoid such elaborate setups and use the FR-2LE entirely on its own. The FR-2LE does have a USB out option, so you can interface it with a PC and route digital data via the USB bus. Keyboard and internal editing functionalityIt is often the case, particularly in electronic news gathering, one wishes to make quick edits of audio material using the recording device itself, rather than transferring files to a PC for non-linear software edits. The FR-2LE lacks this type of functionality. You cannot interface it with a computer keyboard, nor can you do sophisticated audio edits with it. You can do some simple editing, but most of the more complex editing will have to be done on a PC. All-metal constructionWhile the FR-2LE does have a sturdy chassis, the exterior is made of plastic. The plastic does have a decent feel to it. The device does not appear to be flimsy or cheap, but if you need an all-metal build, you will have to look elsewhere. ConclusionWhile many of us might still be lusting after the Sound Devices 722 recorder, the Fostex FR-2LE will do just fine for me. With proper technique, and a properly matched microphone, this recorder delivers very good results. Yes, it is absolutely crucial to use a microphone that matches the input characteristics of the recorder and will not require too much gain. I recommend using battery-powered condenser microphones of medium sensitivity. You can read more about matching microphones with recorders here. Avoid turning the gain all the way up. Try to calibrate your microphones at around -18 to -12 dBFS. If your signal-to-noise ratio is high, you don't need to have high recording levels. You can always bring them up in post processing, if need be. The Fostex FR-2LE is a bit of a revelation to me. It is relatively inexpensive, yet has a feature set and performance of much more expensive products. I look forward to using the Fostex FR-2LE for most of my field recording needs. Download original files
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Several years ago, while we were witnessing the advent of digital sound recording technologies, many of us were not satisfied with the quality, reliability, and usability of early digital field recorders. Many of the technological challenges were identical to those of analog devices (e.g., microphone pre-amplifiers, sturdy construction, long battery life, etc.), but at least two new major hurdles occurred: (1) sufficient miniaturization and low cost of A/D converters and digital chipsets, and (2) reliable, solid-state storage media. 
