Dawn in the forest

After a couple of weeks when the dawn has been too wet or windy for recording, I finally made it up to Haldon Forest for the August recording of my year-long project.

Unfortunately the wind was carrying the sound of the A38 main road across the forest to where I was recording, and even after filtering there is still some traffic noise audible. For this reason I've made this month's track a condensed version with only the most interesting bits of action.

After remaining quiet all summer, the Fallow Deer are becoming more vocal as they approach the rutting season. A group of seven deer crossed the road only metres from the car as I was recording, including the first antlered stag I've seen this year.

Also heard in this recording are a couple of summer migrants, now close to the end of their stay but still making their voices heard. First of all a Nightjar, which actually swooped overhead, silhouetted against the dawn sky, before it called. Towards the end of the recording a Chiffchaff also breaks into song.

Partially baffled boundary array

This recording was the first field test of a new type of stereo array for my AT4022 microphones. Drawing on the design of Crown's "SASS" microphones and also the research of several members of the NatureRecordists Yahoo group, this features two angled wooden boundary plates with an acoustic  foam baffle between them. My initial feeling is that it significantly improves the width and localisation of the stereo field - comments and opinions are very welcome!

Even when things don't go quite to plan with the recording it's still wonderful to be out in the forest so early in the morning - driving back I caught a glimpse of fog around Exeter, so I made a detour to a point where I could look down onto the city rising out of the morning mist.

Exeter surrounded by fog

Posted from Newton Abbot, England, United Kingdom.

It's now late July, and the dawn chorus is virtually non-existent. With breeding over most of the birds are busy feeding on the abundance of insects and seeds around the forest and are quiet except for occasional contact calls. In the distance a Nightjar calls over the scrubland, and then falls silent as the light grows. Tawny Owls and a Kestrel can also be heard, before a group of Ravens arrive in the area. Towards the end of the piece a Great-spotted Woodpecker flies in and begins feeding on a nearby tree.

This is actually a condensed version of an 80-minute recording, with passing cars/aircraft and long periods with little or no activity removed. The Raven segment has been left pretty much intact however, to include the wide variety of different calls the birds produce.

Recorded with 2 x AT4022 omnidirectional microphones in a parallel boundary array, connected to a Tascam HD-P2 recorder. Filtering applied with apQualizr to remove distant traffic noise, and levels boosted by 20dB for easier listening.

Posted from Newton Abbot, England, United Kingdom.

Shapwick Heath (© Li-Li Williams 2010)

These two recordings come from a weekend spent in the Somerset Levels, one of south-west England's richest wildlife habitats. An area of peat moorland less than 5m above sea level, the Levels have endured centuries of agricultural drainage and peat extraction. Several nature reserves have now been established, collectively refereed to as the Avalon Marshes. Consisting of thousands of acres of rough pasture, flooded peat workings and moorland, the marshes are now an important habitat for breeding and wintering birds.

The first track is from Shapwick Heath National Nature Reserve (NNR) and was recorded at 9:30pm. Shapwick Heath and the adjoining Ham Wall NNR support a large population of introduced Marsh Frogs (Rana ridibunda). The origin of these isn't clear, but they seem to have been around for many years. In this recording the microphones are positioned beside a marshy pond, surrounded by trees. A cloud of mosquitoes over the water create a drone loud enough to register on the recording, although you may need to listen through headphones for the full itch-inducing effect. As the Marsh Frogs begin croaking a Tawny Owl hunting over the marshes joins in with an occasional hoot.

The second recording was made at 5:15am the following morning in Ham Wall NNR, from a hide overlooking a flooded peat working. The reason for using the hide will become apparent during the recording when a sudden rain shower passes through - the weather that morning was far from ideal! Again we hear the Marsh Frogs, although as the daylight grows they become much less vocal. A pair of Mute Swan were feeding on submerged plants just in front of the hide - you can hear them calling to each other with quiet grunts, and occasionally blowing bubbles beneath the surface. Also listen out for the cow which is clearly trying to pass itself off as a booming Bittern!

We never did hear a Bittern that day, but we certainly saw one - what both Lil and myself had taken to be a large tuft of grass about 10m in front of us on a grassy track suddenly spread its wings and flew away across the marshes. Shows just how good their camouflage is!

Posted from Bridgwater, England, United Kingdom.

Posted from Cheriton Bishop, England, United Kingdom.

The AT4022 is an omnidirectional microphone, meaning it is equally sensitive to sound from all directions.¹ Because of this, an ORTF set-up like I was using with the RØDE NT1As would deliver very little in the way of stereo. Instead I've mounted the microphones in a parallel boundary array, based on the work of Curt Olson and other contributors to the Naturerecordists Yahoo group (photos below).

These recordings are from a morning spent testing the new rig on the sand dunes at Dawlish Warren NNR. The microphones are connected to a Tascam HD-P2 recorder, and the only post-processing is a gain boost of around 20dB to save you turning up your speakers!

Whitethroat (Sylvia communis)

Skylark (Alauda arvensis)

Initial thoughts - the self-noise of the microphone is definitely more noticeable that that of the NT1As² but the recordings have a far more natural feel. With the NT1As I always "knew" I was listening to a recording, whereas with a good set of headphones it's possible to completely lose yourself in the AT4022 recordings and feel like you're back in the field listening to the birds. My guess is this is partly down to the more even frequency response of the new microphones, along with the better stereo field created by the parallel boundary array.

The recordings were made on a fairly breezy morning, and the only protection on the microphones was the simple foam cover provided in the box. Aside from a few particularly strong gusts I had no trouble with wind noise while recording - another advantage of omnidirectional microphones which are typically much less sensitive to wind than cardioids.

Posted from Exmouth, England, United Kingdom.

1. Theoretically anyway. In practice the response pattern becomes a little uneven at higher frequencies - see this diagram: http://eu.audio-technica.com/en/resources/e873eb8efe56cafc_at4022_polar.jpg [↩]
2. The AT4022 is rated at 13dB(A) self-noise as opposed to the  5dB(A) of the NT1A, one of the quietest consumer microphones available [↩]

For more information on this incredible project, have a look at the A1 Steam Locomotive Trust's website.

In this recording, No. 60163 Tornado bursts out of Kennaway Tunnel onto the sea wall at Dawlish, whistling to the spectators who have gathered to watch it pass by. The sound of the engine fades into the distance, but the whistle can be heard across the water until the train rounds the curve at Langstone Rock and heads inland up the River Exe.

The recording was made from a breakwater which juts out into the bay about 100 yards from the sea wall, using an Audio-Technica AT825 stereo microphone (in a Rycote windshield - the wind is always blowing out there!) and a Tascam HD-P2 recorder.