Audio presence - sensitive - loud ambient sound...

F

frankmcma

Member
Just got the 150 and doing some tests. Everything seems OK on defaults except audio, there is a fairly pronounced ambient sound, like the meters are cranked to 11. Audio picks up fine but it seems like it is up a lot. Any setting to make it a lot less sensitive?

Thanks
 
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Just found an example in another thread

http://edwardkishel.com/HMC150 in quiet room.mpg

He is demonstrating the sound of the zoom

However what I am talking about is the fuzz...the loud ambient sound of nothingness that is very high through the entire clip. I hear it as soon as I plug in my headphones with the built in mic.

Is this normal? Is there a setting to change?

I thought the automatic gain turned off would do it but it did not.

Does anyone else notice this?

Thanks
 
What did you have the gain set to?
If you look at the LCD monitor during recording do you see a constant high signal?
 
I have the volume knobs in the middle, straight up, normal. As for gain, did you mean in the menus? It's 50db or 60db and I have it on the default of 50. Automatic gain (ALC? I think) is set to off.

The hiss is present even with an external mic (set to record on both channels) and even with no mic. If I set it to external mic even before I plug the mic in I can hear the hiss. When I use a mic it records the hiss. The built in mic records it as well.

The sound almost sounds like the volume is cranked overly high, just a loud ambient sound. However meters are fine.

There has been a few mentions on the boards about the loud hiss, and I figured it was the built in mic...but now I hear its there even without a mic and with external mics.

It should be easy to reproduce..set camera to mic inputs...don't connect a mic..put headphones on and turn them up like halfway. You should hear fuzz. Does this occur with anyone? If not I must have a bad unit.

If someone could try this test..I am very curious the results.

The video tests look great, but audio is unacceptable.

Any ideas??

Frank
 
is the headphone volume cranked up to high? Or is this happening with playback outside of the camera? Also, do you the have the mic input set to -50 or -60 dB in the menu?
 
I tried -50 and -60 with little difference. Is there a better setting for less noise?

The headphone volume is normal, in the middle.

This clip from another thread is a great example of the white noise that comes from mic:
http://edwardkishel.com/HMC150 in quiet room.mpg

He was demonstrating the zoom noise..but listen to the large amount of noise generated from the camera in a quiet room.

Again...I get some of this noise when all the mics are shut off. I can hear it through the headphones.

Ideas? Anyone else have the same?

Frank
 
yeah I know, that's my clip. The onboard mic is what I would call "cautiously acceptable" in quiet environments, as I ranted on about this several threads ago. Too sensitive, and it picks up too much motor noise. The white noise is not quite as objectionable to me vs. motor noise. I eventually had to accept the fact that this cam should have an shockmounted shotgun mic.

Do you have this white noise with an external mic away from the camera?
 
Sounds like there might be some kind of compressor turned on (ALC?), which would make the loud parts quieter (or normal in this case) and the quiet parts loud, to the point where you'd hear ridiculous room tone and every creak and crack and hum from the camera body.
 
Ed it's funny..I know you were demonstrating the zoom noise..but I was like..what about the white noise! haha

To me that was the most prevalent. You mentioned an shotgun mic, thats the problem, using external mics, some of the white noise still comes through, enough to be noticeable. I tested with mics and without, just flicking the mic off the internal and then not having a mic hooked up. Record. You'll hear it.

And actually you can hear it without recording. Just turn the audio monitor up halfway with headphones with no mics plugged in or on.

Humanwire - ALC is turned off but that is the exact symptom.
 
If you record some audio and then look at it in a waveform monitor, is there a good signal to noise ratio. That is what is important. Almost any signal if amplified enough will have white noise, its the s/n thats important.
 
Don't use external phantom power and make sure you use a high quality Xlr cable. Changing from a low quality cable to a high quality cable reduced my ambient noise by about 70%!!!
 
I am not using phantom power..but curious about a "high quality" XLR cable.

I have a standard cable..silver ends...black rubbery cord...standard cable available at any music guitar store. Is there higher end brands? Is there features I need to look for? What is the cable you got that improved ambient noise by 70%...I need one of these!

Thank
 
Found these at my local Guitar Center store, they were pricier but the guy working there raved about them and said he only uses them in his studio
 
I´ve done some soundtesting with my HMC 151. Recorded some piece of music played back with my Genelec monitors with a Rode NT5 Mic on a seperate mic-stand. The HMC was set to -50 db and mic ALC with max peak at about - 8db (the input knobs set to middle position).
The I recorded the same music, same mic position with the same max peak with my Apogee Ensemble to Logic Audio.
The Apogee was slightly better over all, but the HMC performed pretty well IMO.
There was no disturbing white noise or hiss in the HMC recordings.

Don´t buy too expensive cables. One year ago I´ve ordered a 200 Dollar cable, compared it to a 15 Dollar cable and returned the expensive cable back as quickly as I could.
Sorry for my bad english, I´m from germany.
 
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