+1 on keeping the Noise Filter off. In my quiet backyard you cannot hear me talking standing right underneath it with noise filtering on. Turn it off and I can hear my next door neighbor fart from 100 feet away LOL.
Dahua PTZ DH-SD50225U-HNI should audio over IP be available?
- Thread starter toastie
- Start date
I did some more audio tests today with this PTZ camera. The best of my electret microphones is a AOM-6738L made by PUI, 9.7mm dia, 6.7mm in height. There was no apparent advantage in adding another small electret microphone in parallel. The audio output from this electret insert is modest at best, probably OK for a microphone designed to be attached to a lapel. Sounds from a distant radio or me whispering were much more quiet, rather too quiet.
To enable or disable the Noise Filter in the Dahua's camera audio configuration - is a subject perhaps on which there seems firm opinions being expressed.
Here with this camera with the Noise Filter disabled there's a background of internal machinery noise coming through, mostly blotting out any external sounds. With the Noise filter at 100% there's little of the machinery noise but little too of any external sounds getting through. So far my compromise setting is to have the Noise Filter on at 40%. I might adjust this when I finally mount the camera on the wall.
I'd just about given up on my idea of including a microphone insert, it wasn't a big deal anyway. If it had worked better my plan was to mount the microphone over a window I would make in the PFA120 mount that I'm using. I tried then holding the microphone at the end of a kitchen funnel and was slightly surprised at the better sounds I was picking up. Next I poked the microphone insert down the swan neck of the camera mount and was again surprised that far from the sounds being more muted I was hearing more than if the microphone insert was in clear air. So this is what I'm going for, the microphone insert stuffed down the swan neck of the camera mount. With no additional connections needing to be made when I'm up the ladder, and me more than half concerned about me falling down, I'll only have the IP cable ( dialectic compound plus PVC tape or self-amagamating tape to wrap around) plus the 24V plug and socket in the wall mount to connect up. I'm not using PoE+.
If the audio I pick up works or it doesn't it won't matter, but a bonus if it does.
To enable or disable the Noise Filter in the Dahua's camera audio configuration - is a subject perhaps on which there seems firm opinions being expressed.
Here with this camera with the Noise Filter disabled there's a background of internal machinery noise coming through, mostly blotting out any external sounds. With the Noise filter at 100% there's little of the machinery noise but little too of any external sounds getting through. So far my compromise setting is to have the Noise Filter on at 40%. I might adjust this when I finally mount the camera on the wall.
I'd just about given up on my idea of including a microphone insert, it wasn't a big deal anyway. If it had worked better my plan was to mount the microphone over a window I would make in the PFA120 mount that I'm using. I tried then holding the microphone at the end of a kitchen funnel and was slightly surprised at the better sounds I was picking up. Next I poked the microphone insert down the swan neck of the camera mount and was again surprised that far from the sounds being more muted I was hearing more than if the microphone insert was in clear air. So this is what I'm going for, the microphone insert stuffed down the swan neck of the camera mount. With no additional connections needing to be made when I'm up the ladder, and me more than half concerned about me falling down, I'll only have the IP cable ( dialectic compound plus PVC tape or self-amagamating tape to wrap around) plus the 24V plug and socket in the wall mount to connect up. I'm not using PoE+.
If the audio I pick up works or it doesn't it won't matter, but a bonus if it does.
sebastiantombs
Known around here
I decided to work further on this until I run out of steam, there's something about the balance between work and effort v potential benefit and rewards.
On a previous test on our living room carpet I separated the microphone insert from the camera using about 3 feet of screened cable and the machinery noise was still present. A 30% setting on the Noise Filter would seem to keep this quiet enough. Today I used a 5v separate power supply to the electret insert via a 1k resistor and a 1.5uf audio coupling capacitor, the audio output was about as low as before. I think it needs a pre-amp. I haven't enough room in the PFA120 mount for a Microseven M7WP-MIC, perhaps just enough for a pre-amp. Thanks for the suggestions about using a PoE splitter. Though I haven't enough room in the mount for a splitter too, I could have the splitter in the attic and run a short length of bell wires along with the other cables in the conduit to power a mic pre-amp in the mount.
Tests here are still ongoing, the camera is not going up on the wall just yet.
On a previous test on our living room carpet I separated the microphone insert from the camera using about 3 feet of screened cable and the machinery noise was still present. A 30% setting on the Noise Filter would seem to keep this quiet enough. Today I used a 5v separate power supply to the electret insert via a 1k resistor and a 1.5uf audio coupling capacitor, the audio output was about as low as before. I think it needs a pre-amp. I haven't enough room in the PFA120 mount for a Microseven M7WP-MIC, perhaps just enough for a pre-amp. Thanks for the suggestions about using a PoE splitter. Though I haven't enough room in the mount for a splitter too, I could have the splitter in the attic and run a short length of bell wires along with the other cables in the conduit to power a mic pre-amp in the mount.
Tests here are still ongoing, the camera is not going up on the wall just yet.
looney2ns
IPCT Contributor
You can save yourself a lot of pain and suffering by not reinventing the wheel.
I will lay odds that your are picking up RF noise that makes you think it is "machinery noise'.
Just buy one of these, use a 500ma or less power supply, and your done.
Mount the MIC, 4-5' away from the camera, using GOOD shielded microphone cable, such as Belden, otherwise it will pickup noise.
Amazon.com : Microseven M7WP-MIC Waterproof Outdoor Microphone for M7B77-POE, M7B57-WPS, M7B77-W, M7D77-POE, Any IP Network Camera & PTZ IP Camera with Audio Interface -an IP Camera External Microphone : Electronics
Amazon.com : Microseven M7WP-MIC Waterproof Outdoor Microphone for M7B77-POE, M7B57-WPS, M7B77-W, M7D77-POE, Any IP Network Camera & PTZ IP Camera with Audio Interface -an IP Camera External Microphone : Electronics
www.amazon.com
As an Amazon Associate IPCamTalk earns from qualifying purchases.
sebastiantombs
Known around here
looney2ns
IPCT Contributor
I'm sure the Microseven would fit the bill but access to the soffit where I would need to go is very awkward, I know because I spent ages getting some flexible conduit through for the camera's cables. Thanks for your help but I'll stick with my plan to reinvent the wheel which is easy enough.
I've has another look at the listings for the Microseven M7WP-MIC which I'd earlier rejected because of its large size. I now see different dimensions being quoted, 16.8 x 8.6 x1 cm on one website, 4.75 x 7.75 x 2 ins on the Microseven website, 6.6 x 3.4 x 0.4 ins on Amazon.com
However much I would have liked to fit this microphone it seemed rather too large, then I saw a youtube review where it's been held in someones hand, it's smaller than I was expecting.
Looking down the Amazon.com listing the microphone has shrunk in size to L 2.5 x D 0.75 ins which fits with the YouTube clip and means it would fit too in my camera mount.
Though it's not currently available on Amazon UK, it is on on Amazon.com. Before I choose to buy will someone confirm the size of this microphone.
However much I would have liked to fit this microphone it seemed rather too large, then I saw a youtube review where it's been held in someones hand, it's smaller than I was expecting.
Looking down the Amazon.com listing the microphone has shrunk in size to L 2.5 x D 0.75 ins which fits with the YouTube clip and means it would fit too in my camera mount.
Though it's not currently available on Amazon UK, it is on on Amazon.com. Before I choose to buy will someone confirm the size of this microphone.
looney2ns
IPCT Contributor
