Audio Technica AT897 shotgun mic question, recording above actors?

[Airwolf]

I've constructed a boom pole, purchased a Audio Technica AT897 and 25' of XLR cable. I was testing it out today just holding the shotgun mic itself in a completely silent padded room. I connected it via mini-plug to my zoom H2 recorder. When recording i tested several different locations, first was right infront of my face, which sounded fine. When i hold it above my head however, maybe 6 inches to 1 foot away, the sound is not as deep as it was when it was right in front of me.

Obviously it is further away but there must be something else. I read several reviews on this shotgun mic and it seems to be one of the best for my budget for a mic, which was under $300. Any advice on how to capture good deep audio from the subject while this is held on a boom pole above the talent? I really want my audio to sound as good as possible. Thanks.

 

[Will Vincent]

Well, you don't ever want it directly overhead, then the top of the actors head is blocking the majority of the sound.. you want it out in front, at an angle pointing down toward either their mouth or chest. You'll get a bit more low end from the chest area, but it still will seem lower than if your mouth is right on top of the mic, nothing will change that.

This is why we spend time in post production sweetening audio and rerecording lines as needed.

The other thing that may help if you feel like your signal is weak and thin sounding would be a tube mic pre-amp

 

[Airwolf]

Ok, did some more testing and having it pointed at more of angle does work much better.

I also seem to be getting a fair amount of audio hiss when it's further away from the subject. Say maybe a foot infront of them. I can remove the hiss using noise reduction filters in post but there must be a better way, as most of those filters usually take sound away from the final project.

Unfortunatly i didn't buy a pre-amp, is this like a beachtek adapter? I'm going to be doing some filming on sunday and wanted to try and have everything ready but completely forgot about needing a device inbetween the recorder and the mic to balance the levels. Thanks.

 

[Will Vincent]

The hiss you're hearing is likely due to the camera's auto-gain cranking the input levels up to compensate for lower volume levels. Beachtek adapters come in a couple varieties, there are some that have a preamp, some are passive connections, they all output a constant signal level that will prevent the camera's gain from ramping up and down.

 

[Airwolf]

For this test i'm not recording to the camera though. I'm recording straight into my Zoom H2 recorder. All default settings and standard mic input. I tried it on the camera and i get the same white noise. Any suggestions on how to stop this? Thanks.

 

[Will Vincent]

Increase the signal (dialogue) level... ie: have your actor(s) talk louder, or get the mic closer. When the signal to noise ratio is high you don't hear the noise, when that ratio drops, the noise becomes more audible.

Ideally you want the gain on your input at the lowest setting necessary to record a good level signal, if you have to crank up the gain, then you're adding additional noise to the equation. A mic preamp might be just what you need to fix this. There are some decent preamps that are pretty inexpensive. I've got a behringer tube pre amp, that I swapped the stock tube out for a higher end tube... It warms the sound, and will give you a little extra power on your input. Also it's got phantom power, which will give your mic more sensitivity.

This is the one I've got: Behringer Tube Ultragain Mic100 Preamp and I swapped out the stock tube for a "Groovetube" which as I recall ran about $25. But even just the stock tube should give you better results than you're getting now.

 

[Airwolf]

In the event i can't get a preamp, how should i best use what i have to get the best sound?

Also i notice most of these preamps require an external power source and are not battery powered, how do i deal with this in the field? My mic for example runs on a AA battery. Camera is battery powered, as is my recorder.

 

[Will Vincent]

Since they all use a wall-wart to get DC power from the AC wall outlet, I would think you could probably rig up a battery pack for a preamp.

As for getting the best from what you've got, get as good a recording as possible, and then clean it up in post to remove any errant buzz, hiss, etc. I've heard good things about the noise removal tools that come with Audacity, and it's a free program, so you can't beat that price.

 

[Dave Pastecchi]

hi Air....are you sure the HISS is not the sound of the room itself...it can be something running in the room..say like a computer and when the gain is up on a mic it will pick this up...also as stated above in a few posts...bad preamps will cause a hiss as well when mic gain is boosted up high....

using a shotgun indoors always opens up a bunch of problems and getting more warmer sound from that mic may never happen...but yes..always point to the chest from above about 8inches from in front of your actor (if you can) ...lighting and frame may keep you out of that sweeter spot...you can even try comming from below sometimes (if frame allows...and if there are no Head Turns to deal with) ...above is always better...but there are options....

if you are shooting indoors and mostly in Med to CU range or even Wide shots, but the headroom is kept low...say like for TV shooting.......a hypercardiod will always sound better because of its off axis response is always better than a shotgun...and will give warmer sound...i always refer to my Scheops as a shovel...because even off axis it scoops in the sound with a warm smooth texture...

be well and hope some of this helps

 

[Airwolf]

I purchased a bluetube tube amp and the hiss dissapears. Problem is this device is not really portable at all so it causes some problems as far as mic portability.

 

[spinner]

hi Air....are you sure the HISS is not the sound of the room itself...it can be something running in the room..say like a computer and when the gain is up on a mic it will pick this up...also as stated above in a few posts...bad preamps will cause a hiss as well when mic gain is boosted up high....

...did you check the sound of the room? Also, the lights IN the room might effect it somewhat. You might be getting a hum from the flourescents. I remember once when the neon lights interfered with some lav mics when I was in a studio...


-- spinner

 

[Will Vincent]

The hiss that Airwolf is talking about is very definitely that caused by the preamps in the camera working hard to balance the signal. Adding a preamp (which the bluetube would be) or otherwise feeding the camera a constant input level (with a beachtek adapter) is about the only ways one can prevent this hiss. It's white noise (or maybe it would be pink noise, I'm never totally clear on the difference) caused by the inferior mic preamp(s) in the camera compensating for an audio source it was never designed to handle.. the result, noise.

 

[Dave Pastecchi]

after reading more of this post...i would have to agree it is the camera's cheap preamp making this hiss...

the best fix (for the money) would be a beahtek adapter...it will bost the signal of the mic but and has a better preamp than the camera...so this should fix that problem..and allow you to use a balanced, shielded input from the mic as well...i am not sure what model has phantom and T power on them, but if they do...that is the one i would get..i believe its the DXA 6VU...DO NOT get a passive one...this will do nothing for you...and you will still need a phantom/t-power supply if you get a passive one...

hope this helps a little