I am interested in recording sounds for natural history projects. I realize that is a surprisingly difficult task as one has little if any control over the subject or competing sounds. Another problem is that sound levels are likely to be low so that recorder gain levels have to be high.

I have been comparing the specifications of the Rode NTG-3 and the Rode NT1-A. Signal to noise ratio and equivalent noise seem to be better on the latter but it is classed as a studio microphone as distinct from a field microphone.

My question is what sets a field microphone apart from one for studio use only. Is the field mic better able to resist damage in the field?

I get the impression that the NTG-3 is admired for its ability to withstand humid conditions. If humidity is the problem would storage with silica gel between uses solve this problem?

I have several NT-1As and they are extremely quiet. Unfortunately because they're large diaphragm condensor microphones they have several issues for field use.
One as you've noted is the issue with humidity which I address by keeping them in sealed cases with FRESH silica gell. The second issue is they're sensitive to wind and fast pressure changes. That large diaphragm can easily bottom out making for some nasty noises, even indoors I use mine with a popper stopper. Lastly as the NT-1A is a cardiod you may find its ability to reject unwanted sounds an issue in the field.
The NT3 would be a much better choice for your application.

Alastair, Microphones are like golf clubs. Each one has a task it's best suited for.
Sure you could drive with a putter, but selecting a driver would prove to be a better choice.

Here is a little light reading to get you caught up.
Microphone - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Microphone)



All the Best!

A microphone for use in the field needs to resist moisture and to easily be windshieldable in a basket windshield (like a Rycote (http://www.rycote.com/)).

An RF condenser is normally the mic. of choice as it will work well under damp and humid conditions and not go noisy and crackly like normal AF condensers do.

The Sennheiser MKH 416 dropped about 20% or so in price recently - and also - they were showing the new MKH 8060 and 8070 at the European AES in London last week.

You may find the website of the WSRS - Wildlife Sound Recording Society (http://www.wildlife-sound.org/) useful.

Thanks Bob, David and John for your replies.

I should add that most of the recording I do is at night in timbered country. Even a gentle breeze produces so much noise from leaves etc that my recordings are adversely affected. Instead of trying to record under these conditions I wait for a windless period, the same conditions that a large diaphragm microphone seems to need. Furthermore the recording period tends to be short as the animals tend to have limited periods of peak activity. Given time one can learn when and where the animals are likely to call.

It seems then that my major problem is moisture. I presume the effects are reversible given the right conditions and sufficient time? I would be happy to store the mic with fresh silica gel.

I can see the advantages of a directional microphone particularly if you know beforehand where the animal is. I know that with a shotgun mic the longitudinal axis of the mic is directed to the source. What axis of a large diaphragm mic like the Rode NT1-A is directed towards the subject to take most advantage of its cardiod pattern?

Have you considered the use of a parabolic reflector with a microphone, Sony produced one many years ago (PBR-330)I have used them on Golf Outside Broadcasts with good results.
Parabolic reflectors have 2 major problems... little bottom end frequencies and they get blown around a bit in high winds.
But could be worth a try.

...What axis of a large diaphragm mic like the Rode NT1-A is directed towards the subject to take most advantage of its cardiod pattern?
Like most large-diaphram mics, the NT1-A is a "side-address" mic, meaning, the side with the logo on it should be pointed at the source.

One thing that's not been mentioned beyond humidity - in general, a large-diaphram mic is much more delicate, susceptible to everything, including mechanical shock, wind, moisture, dust, you name it, it either messes up the sound or breaks the mic. I don't know how durable an NT1-A is...

Thanks Seth,

I had wondered whether durability was a consideration in deciding whether a microphone was considered suitable for location work.

My dealer has just received a reply from Rode on whether an NT1-A could be used outdoors and the reply was: - "The NT1-A can certainly be used in this situation in conjunction with a WS2
wind shield and a DeadCat if moisture is an issue".

Hi Brian,

Thanks for the suggestion, I have a 20" reflector that I used to use with a 240 volt 2000 watt lamp for underwater filming. It should not be hard to adapt for a test. Buffeting by wind will not be an issue for reasons stated above.

Do you happen to know if the 330 in the PBR-330 was its diameter in millimetres?

So let me see if I get this straight, you sit out in the forest and wait for no wind, then hope that the animal in question comes by so you can record it? Jeeezz I thought waiting for airplanes to pass was tedious!

The PBR-330 would have been about that 330mm Dia and was easy to (one) hand hold. I have also used a bigger version called "big ears" which was a 2 hands hold.
Do a google search there are many versions out there,
The important thing with parabolic dishes is that mic faces INTO the dish and mount it at the focal point of the dish (and away from the sound) The Sony instruction suggested using either omni or cardioid mics. Cardioid mics created a longer throw/ pickup where as the omni gave a better bottom end.
I used them on a couple of interesting jobs in surveillance, it picked up a conversation at 100m+ and the other job was at a prison siege where we heard the demands..... got the sound no problems. Crews with short shot gun mics just reported with what was said.

Brian,
Good to hear about your experiences with the parabolic microphones. I checked the specs of the Big ears. They use a Senn lav mic. The B&H description says that it has a range of 500 feet and the Lil ears range of 300 feet. That should be good for natural history recordings. However, it might be difficult to hold the Big ears with both hands. Seems like there has to be a dedicated person to handle this. However, I am still not sure whether the cost of 3000 usd and 4500 usd for the Lil ears and Big Ears is justified.

Cheers,
Sabyasachi

Considering the congenital limitations of parabolic microphones, those prices seem preposterous. But perhaps if you aren't recording anything with any low-frequency content, you might get away with it.

Over in the Yahoo forum "naturerecordists", the NT1-A is frequently mentioned as a popular choice.
http://tech.groups.yahoo.com/group/naturerecordists

I keep looking at my wok (or buying another one from the Chinese cheap store) and thinking of making a mould out of it in fibreglass.
Just have to work out the focal point.

Thanks Seth,

I had wondered whether durability was a consideration in deciding whether a microphone was considered suitable for location work.

My dealer has just received a reply from Rode on whether an NT1-A could be used outdoors and the reply was: - "The NT1-A can certainly be used in this situation in conjunction with a WS2
wind shield and a DeadCat if moisture is an issue".

Certainly you can use the NT1a outdoors, given adequate wind protection. The issue is how practical is it to sling something with its size and weight on the end of a boom and since it is side-address, the difficulty of keeping it aimed optimally when following action. "Field mics" are typically end-address, lightweigt 'pencil' mics much easier to handle on a boom.

Just about the biggest feature of the NT1-A for nature work is its very low self noise so you can wind it right up. The negative side .. there's no low cut so the slightest breath on the capsule will be heard. It won't fit the Rode Blimp, and some might find needing 48V a problem.

Some of the best nature sounds I've heard are stereo with a great soundfield at night. The Rode NT4 is stereo will take a 9V battery, no low cut but it will fit in the Blimp. The response is 20-20Khz and for nature work it'll stand some high frequency roll off when in the Blimp. I tape some fresh silicagel sachets inside the Blimp with it.
Cheers.

Thanks for the continuing interest in this post. I have done some reading on parabolic reflectors. Low frequency problems seem to be related to focal length of the reflector as well as to its diameter. Better low frequency responses are apparently to be had from large diameter short focal length reflectors. I am sure that the directionality of the reflector could be an advantage if you know the exact source of the sound, however as I am interested in nocturnal animals that may call briefly and occasionally and possibly while moving, this directionality may not be such a good thing.

Currently I am exploring the possibilities of the Rode NT1-A. I have experimented with the NT1-A in a Rode blimp but have had trouble with handling noise, padding the blimp handle with sponge rubber proved to be ineffective. However I have found that suspending the Rode shock mount from rubber bands eliminated the handling noise problem. With the extra level of isolation I can now use the full gain of my recorder without being bothered by handling issues. Another problem with the Rode blimp is that it uncomfortable to use with a side address microphone.

Unlike the PCM-D50’s inbuilt mics the NT1-A seems not to be unduly sensitive to wind noise.