Directional microphone for PTZ nature cam

OldGuy

n3wb
Joined
Sep 21, 2021
Messages
4
Reaction score
3
Location
Indiana
Hi folks. I have a Dahua SD49225XZ-HNR (thanks, Andy) pointed at my bird feeders. I'd like to get better sound specifically from that direction than I'm getting today.

I researched microphones for PTZ and related topics here on the forum. I chose the Microseven M7WP-MIC, wired it to my 49225 and mounted it pointing at my feeders. I've found that while that mic does pick up sound well, it does so from almost any direction. The ambient sounds (such as cars on the road) are much more pronounced than the sounds of the birds which I'd like to hear. I've tweaked numerous settings in both BI and on the camera itself (Encode Mode, sampling frequency, etc.) with no improvement.

I'd like to find a mic that's more directional for picking up sound, and would appreciate any recommendations.

Member Terri Underhill recommended the Vanxse Mini Microphone High Sensitive Pickup Audio Mic, and commented that it was quite sensitive, perhaps too sensitive.

Anyone have any other inputs on a good external microphone for nature viewing/listening?

TIA.
OldGuy
 

jack7

Pulling my weight
Joined
Mar 21, 2019
Messages
306
Reaction score
199
Location
USA
Try mounting your mic very close to bird feeder with it pointed at where birds will likely be and possibly blocked from direction of road and car noise. Run cable back to camera.
 

DsineR

Getting comfortable
Joined
Mar 25, 2018
Messages
363
Reaction score
465
Location
FL
Outdoor 'shotgun' mics are $$, and may need phantom power.
Low budget fix - try constructing a directional cone around the mic - a DIY parabolic mic.
 

OldGuy

n3wb
Joined
Sep 21, 2021
Messages
4
Reaction score
3
Location
Indiana
Thanks for the replies. My feeders are 30ft out into the yard, making a cable logistically difficult. Makeshift cone, esp plastic funnel is a great idea. I have a set of funnels, and repurposing one of them is very do-able.

Thanks again!
 
Joined
Dec 28, 2019
Messages
11,487
Reaction score
27,428
Location
New Jersey
Let us know how it works out. I built a highly directional mic back in high school, I'm in my 70's now. It used a group of tubes made out of 1/2" EMT starting at six inches long and going up to three feet long. They were arranged in a spiral with all the ends flush at one end of the assembly. A funnel was mounted at that end with a mic at the thin end of the funnel. It was great at very long distances and had an extremely narrow pattern. A lot of work, but it was a science fair project and I was young and dumb enough to build it.
 
Last edited:

Rickoo

Getting the hang of it
Joined
Nov 16, 2019
Messages
199
Reaction score
70
Location
USA
I was trying to accomplish the same thing last year. I thought it would be great to point the PTZ at the feeder I wanted and hear what was going on there. Couldn't find an cost effective way to do it. I ended up wiring Microseven mics at each feeder (2) in parallel. It works great but does pick up sounds like road noise or a neighbor cutting grass or leaf blowing.
 

jack7

Pulling my weight
Joined
Mar 21, 2019
Messages
306
Reaction score
199
Location
USA
Early this year I used the PC program Audacity to try to reduce the background road noise, etc. from a microseven mic in a video recording of an owl nest and owl hoots. It worked to some extent, but was not worth the effort.
I remember reading a post in this forum that the microseven mic without power could pick up sound maybe up to 6-10 ft away. For a mic close to the desired sound source, I wonder if that would be a way to reduce background noise?
 
Joined
Dec 28, 2019
Messages
11,487
Reaction score
27,428
Location
New Jersey
A light bulb just went off in my head. Rather than a standard funnel try one of the funnels used for adding oil to a car. The ones with a really long neck and a slow taper. That may provide better directional capability than a standard funnel.
 

OldGuy

n3wb
Joined
Sep 21, 2021
Messages
4
Reaction score
3
Location
Indiana
Update.

First off, thanks again for the ideas and inputs, folks. I have a funnel set aside for this purpose for the future.

Before doing the funnel thing, I decided to play around with the Noise Reduction settings on the 49225. This has worked surprisingly well, and I'm using it for now.

I adjusted both the Microphone Volume (gain, I believe) and Noise Reduction settings on the camera, one at a time and then together. I ended up with the Microphone Volume at 73 and Noise Reduction at 100. Audio encoding is set to Mode of AAC and Sampling Frequency of 48000 for both Main and Sub Streams. Result is that cars driving by on our country road no longer sound like a roar, but are either completely silenced or sound like running water. I can hear the birds quite well: Finches, Cardinals and various Woodpeckers, all of whom are relatively quiet, come through clearly. Blue Jays, with their loud calls, can be shocking.

I am running the Microseven M7WP-MIC powered by an external 12V supply. The mic is plugged into an RCA jack cable which is in turn hard-wired to the 49225's Audio In. Hard wiring was done by stripping insulation and twisting wires together, then sealing that connection with heat-shrink tubing with overlaps the remaining insulation on both sides of the connection. I scavenged the RCA cable from an old, non-working CD player.

If I end up changing to a directional mic later, I'll update and post that here. In the meantime, I'm enjoying my nature sounds while "working" up here in my office.

And Yes, us old farts gotta stick together!

Cheers!
 

Rickoo

Getting the hang of it
Joined
Nov 16, 2019
Messages
199
Reaction score
70
Location
USA
Yeah, the blue Jays will sure wake you up! I leave a tablet on most of the day with the camera on one of the feeders. I have two mics and they pick up sounds at both feeders. Kinda feels like your sitting outside. By the way, Amazon sells RCA (as well as other types) of connectors that can make easy work of setting things up.


Like you, I tend to solder and heat shrink most of what I do. Do it once and it just works.
 

Alaska Country

Getting comfortable
Joined
Jun 10, 2021
Messages
258
Reaction score
304
Location
Alaska
If you need to process audio take a look at Audacity.

"Free, open source, cross-platform audio software.
Audacity is an easy-to-use, multi-track audio editor and recorder for Windows, macOS, GNU/Linux and other operating systems. Developed by a group of volunteers as open source."

www.audacityteam.org
 
Top