Zoom H2 SD card recorder
The Zoom H2, retailing at around £200, is an attractive all-in-one mic/field recorder, recording onto standard SD cards. Four cardioid microphone capsules are positioned at the top of the unit, two facing backwards and two forwards. These can be used in pairs or all together to capture a stereo soundfield, and an extra mode to capture a surround soundfield onto two synchronized stereo tracks (ie a four-track recording). The mics facing towards the operator are set to 90 degree spacing, and the ones facing the rear are set to a 120 degree spacing. The recorder using two standard AA size batteries, either alkaline or NiMH rechargeable. There is an external mic and line input, which disabled the internal mics if used. Three stages of mic gain are available. Although the format is a handheld recorder, you cannot really use the internal mics handheld as like any cardioid mic the H2 is quite sensitive to handling noise. There is a standard ¼ inch camera thread on the base and a desk stand and extension handle (pictured) are supplied, as well as the foam windshield shown in the photo.
You can select a number of recording modes and sampling rates - 44.1kHz, 48kHz, 96kHz and bit depths of 16 or 24 bits, plus a range of mp3 recording modes from 48kbps to 320kbps. Manual record level is supported, and you can adjust the gain without entering the menu and while recording, using two of the front panel buttons as up/down. These should provide all the options most recordists will need. One-handed operation is quite feasible, and a 2 second preroll buffer is available to catch the start of a vocalisation.
Like many CF recorders, this product is clearly aimed at musicians rather than widlife sound recordists, with a metronome and tuning facility. However, the compact form factor makes it attractive to the widlife sound recordist on a budget, with the built in mics there for soundscapes and the external input available for more specialist mics. However, the high self-noise of the H2 limits its usefulness with external microphones, and the mic input is 3.5mm stereo unbalanced only (plug-in-power is available if selected).
The gain available is also low - the H2 has 23dB less gain available than a RH-1 minidisc recorder. That is a long way short, and would hamper the ability to monitor some sounds in the field.
For instance, the MKE300 recommended as a starter mic has a self-noise of 16 dbSPL and a sensitivity of 16mV/Pa, which is not atypical, so the self-noise is 78dB down on 16mV, ie 2µV, which is -116dBu. The H2 input stage impairs this mics self-noise by about 17dB, which is a serious degradation in performance. You would need to use the device with something like an outboard mixer or a FEL preamp - the latter can be powered by the plug-in-power of the mic input (if it is switched on from the menu option). The FEL SJ3.5 is a good match to this recorder, but the combination is not a cost-effective way of getting low noise - you are better off with a HiMD recorder if wildlife sound recording is your main aim.
The performance using the built-in mics is rather better than this measurement would indicate - here is a recording of a pair of blackbirds chinking in the morning - the nearest one is about 10m away from the H2 and the rear mic was selected. (note this recording has been filtered for urban traffic noise, but not HF hiss)
Either the internal mic capsules are unusually sensitive, or the signal path for these capsules is different to the external mic input. For voice recordings it is worth watching the bass enhancement which makes the voice unnaturally deep at a distance of less than 30cm, but the performance is otherwise good for general field recording.
Settings - gain H level 127 sampling rate 44.1kHz Source impedance 150Ω Software level 1.02
Minimum input for 0dBFS = -43dBu
Ein = -95dBu (unweighted, 22kHz BW)
Ein (A) = -99dBu (A weighted, 20kHz BW)
A plot of the noise floor at maximum gain is shown below, when the noise is boosted by about 50dB a tone can be heard, presumably the 688Hz component, but it is not likely to be too serious in a live situation, as ambient LF noise is still usually significant in this area.
noise floor, normalised to 75% (boosted by 50dB if recorded at full gain, terminated in 150 ohms)
Users should be warned that the polarity of the 9V DC power socket is opposite to the most common usage, with the inner being -ve and the outer being +ve. This is not a problem using the supplied adapter, but users should take extra care to avoid swapping the supply with that of another device.
As a low cost standalone field recorder/microphone combination the H2 is interesting. However, its limitations means it cannot really be recommended for wildife sound recording due to the limited gain and high noise level on the external microphone input. That input is also unbalanced only, and does not offer P48 powering, which constrains the range of microphones that could be used with it. If you are looking for a low-cost solution for use with P48 mics, you may wish to consider the Zoom H4
If used with an internally amplified microphone such as the Telinga stereo DAT-mic, this product could perform well, since the noisy preamp and low gain would be overcome by the internal amplification fo the microphone. The rather nice internal mic array would then give a good alternative mic rig for the wide soundscapes for which the dish would be a poor match, making a more versatile system.
Review date: October 2007