TESTING THE SONY M10
June
(Palm Swifts and Nocturnal birds)
A new toy!
A new machine to hit the market in recent months has been the Sony PCM M10 this has attracted a huge amount of attention as it is a smaller, cheaper, lighter version of its big brother the Sony D50 but with similar performance at a price most of us prefer. Along with the Olympus LS10 (and now LS11) these three seem to be the best of the small pocket-sized recorders which allow linear PCM recording up to 96 kHz/ 24 bit levels from both built-in or external PIP-powered mics.
I was lucky enough to be travelling in Asia and found the Sony M10 in Singapore at a price much lower than it can be found in Europe. There are many reviews that have been made elsewhere by those with much more technical expertise than I, so I will not attempt go through everything here - this is more for posting some field trials with the built-in mic.
I have found the machine extremely easy to use, can be held like a mobile phone and has a great very clear menu. With 4 GB of built-in memory, and the 16 GB card I bought it will give about 16 hours of recording time at 44.1kHz/24bit which is my normal level, at this the two AA batteries are supposed to last 41 hours which is quite extraordinary.
The built-in mics are reputed to be amongst the best of these small recorders and so the whole thing presents a small autonomous unit which can be left running in a target location. My purpose was exactly that and so have been experimenting with unattended and in some cases overnight recordings:
Palm Swifts (Cypsiurus balasiensis)
Palm Swift on its nest in a Chinese Fan Palm (Livistona chinensis)
Impatient to try it out on my travels I discovered a small colony of Asian Palm Swifts nesting in a Chinese Fan Palm in the garden of my hotel. These are great little birds that fascinate me, and which I once studied, they build their nests out of wind-dispersed seeds ("fluff") which are glued in the fold of the palm frond with their saliva, here they incubate the eggs by perching vertically on the nest. The birds were flying around the garden and coming in to their nest calling to each other. I set up the recorder below the tree just after dawn - propped up in my running shoe with the two mics pointed up to the leaf, then retired a good distance to drink tea and watch that no-one pinched the machine !
The first sample is of three cuts with action sequences, no filtering has been applied just a conversion to mp3 format. There is lots of man-made noise as this was close to the hotel and the sea - so air conditioners and boat engines all rumble away:
Palm Swift sonogram
The birds are tiny - they weigh only about 9g and so their call is not that strong and of high frequency - with a fundamental between 3-4 kHz and harmonics beyond 14kHz (where my ears no longer work !!) - the sonogram is taken from this recording and in my view the M10 did a great job of picking up the sound.
This next sample is exactly as above but with equalisation applied below 1kHz to take out those horrible rumbles - you can better appreciate what the machine does at that frequency and what great little birds these are:
Nocturnal Birds
Back at base I have been experimenting with the machine unattended in the forest to pick up nocturnal sounds. This is a bit worrisome as we have a pretty good choice of biting, chewing, stealing nocturnal carnivores that could have fun with my new toy. I bought a small cage-type mouse trap and put the recorder in there strapped to a tree - I assumed that if it kept things in then it would likewise keep 'em out ! I have not yet worked out how to protect it from the elements and still let sound in though....
With the above battery / memory life I can easily leave the machine in place at 2000h and recover it the next morning at 0700 before going to work. The machine has worked perfectly, having now done this for about 6 test nights. When a file reaches 2 GB it automatically closes and opens a new one with seemingly no interruption (or none that has bothered me anyway), this is just over 2 hours recording so I have about 5 very large files to examine the next day (a problem in itself actually). All sorts of weird nocturnal events happen, some of which I can only guess at !
The site where these samples come from is at about 1300m altitude in the Jura mountains. It is 5km in a straight line from the nearest rural public road and 10km from the highway in the valley, aircraft rumble is a perpetual problem. In the full flow of a dawn chorus the machine sounds really great (to my ears anyway) - in the following the cow bells are about 1km away and you can also hear a milking machine generator from a mountain farm about 2kms distant, no filtering was applied, about 0600h:
However in the quietest of moments the self-noise of the internal mics is clear, here is a sequence (no filtering) on a calm night which is just the forest background at about 0400h:
Once some action happens then the noise is less evident, here is another unfiltered sequence just as darkness falls, the last day singers are running out of steam and a Woodcock (Scolopax rusticola) flies over making his "roding" display calls:
Louder action of course is even better. Here is one of my target species - Tengmalm's Owl (= Boreal Owl) (Aegolius funereus) which performed quite nicely:
So that is where I have got to. I am delighted with the machine - a great take-with-you-anywhere device (that incidentally also has a 5 sec buffer in it as well). But for the quietest of locations would need some better external mics. It does supply PIP and can drive those kind of mics, if I got some I could then put the machine in a water-tight case and run cables out of it.....but how to keep the mics weather and animal-proof for a night in the forest ? Next challenge I suppose.......
