Motor sound?

Don Palomaki · June 20th, 2007, 07:16 AM

Quote:

Don, I'm not using onboard mic....

To clarify, my comment refers to on-camera, which would include the built-in mic, and any mic attached to the camcorder, i.e., in the holder or on the shoe, shotgun or otherwise. It would not apply to the receiver part of a wireless mic system.

Urban Skargren · June 20th, 2007, 07:39 AM

Thanks for you wise words, Don, all advice are welcome.
I'm also not talking first hand about on-board mics here, I don't use them that often. The problem is the noise is in the room where the camera is. For example, I did a short a couple of years ago that had 75% of the scenes in a car with two people sitting 2 feet from the camera. How would you mic that without having the camera noise? Seems impossible to me, because the noise will bounce around in the car and be part of the ambient sound. But that's an extreme example.

Thanks for the frequency, Poppe, I did a quick test and I had better results with a Q of 1,5 but I suppose it will vary according to the program.

Also called my local repairman, he said (this is how I remembered it) the noise could be from the drum/head hitting the tape 4000 times per minute, and at some cameras this noise is worse in the beginning of the camera's life. So we'll have to film like lunatics to wear the parts down in there...

Poppe Johansson · June 20th, 2007, 09:03 AM

Quote:

Originally Posted by Don Palomaki

To clarify, my comment refers to on-camera, which would include the built-in mic, and any mic attached to the camcorder....

Sorry for my misunderstanding. My finnglish isn't the best yet :)

Don Palomaki · June 20th, 2007, 09:30 AM

No problem. I understand Finnglish (USA style) and have been known to speak a bit myself.

David McGiffert · June 21st, 2007, 11:10 AM

I just read this thread carefully.

I DEFINITELY have SERIOUS zoom-motor noise that is picked
up on my Sennheiser ME 66. It doesn't matter whether it's quiet
or loud in the ambient, and it makes no difference having AGC off.

I have tried loosening/tightening the mount holding the mic with no change.
I have moved the position of the mic around, no change.

My kids DV camera (Sony), using the same microphone,
has zero-none-nada zoom-motor sound.
Actually I have never had this problem on the other three DV camera's I've owned.

I love this camera. This is not whining.
But it is inexcusable to have this much noise transmitted to a microphone
on ANY camera much less on a high-end beautifully-done camera like this one.

I am totally open to being wrong about this and would love to hear what
else I can try to solve what, for me, is a critical flaw in this camera.

I know I can probably clean it up with software in post.
But that is a weak solution.

David

Urban Skargren · June 21st, 2007, 11:18 AM

Do you use a rubber suspension or the mount on the camera?

David McGiffert · June 21st, 2007, 11:27 AM

I am using the mic holder supplied with the camera.
A rubber suspension set-up would probably be better (haven't
tried it), granted,
there is precious little space around camera to get to the controls
using the supplied mic holder as it is. With a bulkier suspension set up
it will be really crowded around the controls.
But that might be the best solution.

Thank you.

David

Urban Skargren · June 21st, 2007, 12:37 PM

If you hold the shotgun next to the camera pointing in the shooting direction and listen with headphones you should be able to find how far away the mic needs to go, if the problem is acoustic. I suppose there are always solutions with specially-built longer holders if needed. (you could even have a Z-shaped extendable arrangement built from a desk lamp holder...)
If the problem is internal vibrations I really think a supension should do it.

Don't know if this will help you:
http://www.dvinfo.net/conf/showthrea...ght=suspension
http://www.samys.com/product_detail.php?item=9026
http://www.bhphotovideo.com/c/shop/8...hoe_Clips.html
There's probably a lot more said abot this here if you search on "suspension" either in this forum or the whole site.

David McGiffert · June 21st, 2007, 11:23 PM

Hi Urban,

I am going to try one of the shockmounts you gave me the tip on
(one of the low cost ones from the B&H url).

Thanks, I guess it's the only way to solve it.

David

Bill Watson · June 22nd, 2007, 01:15 AM

I can't hear any zoom motor noise on my XH-A1 at all.

Dan Herrmann · June 24th, 2007, 07:44 PM

Removing hum and noise from audio tracks
How many times have you shot that perfect clip only to notice that you hear a computer whirr or refrigerator fan in the background? Or even worse, during some very introspective and moody dialog, you're distracted by a 60- (or 50-) cycle hum from improperly grounded equipment that made it onto tape. It's a well-accepted maxim that even the most professionally shot video can be ruined by poor audio, so let's look at some ways you can address noisy hums and buzzes in your audio tracks.

Ducking levels
If there's little dialog or required audio, then you can often get by with ducking the levels (aka hiding the nasty bits) during periods of silence.

Use the mixer and automation to simply lower the track volume between words and speakers, and then raise it again when there's dialog. Since the noise you're ducking will still be audible during the dialog—you're just taking attention way from it during periods of silence—it could sound strange to hear the noisy hum return when people are talking. In these cases, try leaving a little bit of the noise in the silent/non-speaking parts of the clip.

Alternatively, if you can record clean audio with another device from another, quieter location, you can mix that into the silent parts to help take attention away from the ducking.

Parametric equalizers
The audio spectrum, from the lowest bass frequencies to the highest treble frequencies, is represented in Hertz (Hz). The human voice tends to fall between 85Hz for a low bass and 255Hz for sopranos, while music instruments fall both below and well above this range.

Equalizers are simply tools that allow you either to raise or lower the volume of specific frequency ranges while not affecting others, exaggerating—or removing entirely—certain ranges of frequencies. Most audio applications include some form of parametric equalizer—as an audio effect, plug-in, or feature. But if you're not an audio engineer or well versed in sound reinforcement, they're not very intuitive. Fortunately, there's not much to them at their roots.

Basic parametric equalizer in Adobe Audition

A parametric equalizer simply lets you specify a range of frequencies and either raise or lower the volume of tones that fall within that range. In Adobe Audition® the controls of the parametric equalizer are as follows:

Frequency: the target frequency
Amplitude (or gain): the amount you'll cut or boost the selected frequency
Width (or Q): the width of frequencies that will be affected around your target
Note: Although the terminology used in your software or hardware unit of choice may be different, these three functions are essentially what define a parametric equalizer. Some cheaper/lower-quality parametric equalizers do not include a manual width control, however.

In Adobe Premiere® Pro, the Parametric Equalizer plug-in is actually a group of parametric equalizers that you can turn on or off selectively, to affect not just one particular frequency but up to five frequencies at the same time.

In this case, we want to lower the volume of a single frequency, say the whirr of a computer's cooling fan:

Enable the Parametric Equalizer and, next to the Frequency Bands, click the Band 1 check box (make sure the others are unchecked).
Find both a spot in your audio track that's mostly silence and a prominent amount of the noise that you want to remove.
Set the Parametric Equalizer controls as follows:
Q/Width control to 100 (so the equalizer will focus on a very narrow range of frequencies)
Amplitude control to roughly 75% of its highest value
Click the Preview button to play the audio file, and then sweep the Frequency Band 1 slider repeatedly from its highest to lowest range and back again. As you do this, at some point you'll notice the fan noise that you're trying to remove jumping out in the mix and getting quite loud. This means you've found the target frequency.

Pull the Band 1 Amplitude slider down carefully until the fan noise stops offending you. Watch the main graph closely, too; if you push the amplitude up or down too far, you'll notice it has a bell-curve effect on frequencies around it. Make sure to keep that spike as narrow as possible so that you remove only the tones you don't want.

You can fine-tune things by slightly adjusting the Q/Width control, to make sure you're removing only the tones you don't want, and by slightly adjusting the Frequency control, to make sure you're dead-center on the offending fan noise. With Audition's five-band parametric, you can work on up to five different problem frequencies. Just watch the graph and make sure that closely adjacent equalizer peaks don't collide and affect surrounding tones more than necessary.

Always keep in mind that you're cutting out frequencies with this technique, so be sparing with both the Amplitude and Width/Q controls—and be prepared to make some compromises to get the best overall results. There's no substitute for cleanly recorded audio, and any trick like this that attempts to clean things up after the fact will be inherently destructive in nature. Use it cautiously, and let your ear be the final judge.

Urban Skargren · June 26th, 2007, 07:28 AM

Thanks, Dan, for your contribution.
David: I noticed that on my camera the zoom noise differs with different zoom settings. Setting zoom to constant and using the wheel to adjust the speed I found that some speeds have lesser noise than others. Don't know if that's so on yours also.

Some more links I found about shock mounts:
http://www.thej-rod.com/
http://www.dvinfo.net/conf/showthrea...862#post596862
http://www.dvinfo.net/conf/showthread.php?p=595710

Others: are your zoom motors also audible? (Michael Y Wong is also complaining about this in the thread above)

Pavel Tomanec · January 26th, 2008, 01:59 PM

Hi All,

I must admit the zoom noise on my A1 Pal was also bad, I use AKG Blue line mikes. I have removed the Canon mike holder from the camera completely and got decent Rode shock mount. Since then the noise is gone from the recording and also from the headphones when monitoring sound. Shooting with the shock mount makes really big difference, I would highly recommend this to anyone concerned about the sound.

Regards,
Pavel

Pavel Sedlak · January 26th, 2008, 05:24 PM

There is no zoom noise.

Geoffrey Cox · June 12th, 2009, 02:29 PM

Thanks Pavel. I had lots of problems with motor hum and your set-up inspired me. I bought the Rode SM5 shockmount (which looks like the one you've got) and it works plus it simply slots into the A1's holder. Hum gone. It's cheap too!

June 20th, 2007, 07:39 AM	#32
Urban Skargren Major Player Join Date: May 2007 Location: Medellin, Colombia Posts: 225	Thanks for you wise words, Don, all advice are welcome. I'm also not talking first hand about on-board mics here, I don't use them that often. The problem is the noise is in the room where the camera is. For example, I did a short a couple of years ago that had 75% of the scenes in a car with two people sitting 2 feet from the camera. How would you mic that without having the camera noise? Seems impossible to me, because the noise will bounce around in the car and be part of the ambient sound. But that's an extreme example. Thanks for the frequency, Poppe, I did a quick test and I had better results with a Q of 1,5 but I suppose it will vary according to the program. Also called my local repairman, he said (this is how I remembered it) the noise could be from the drum/head hitting the tape 4000 times per minute, and at some cameras this noise is worse in the beginning of the camera's life. So we'll have to film like lunatics to wear the parts down in there... Last edited by Urban Skargren; June 21st, 2007 at 12:10 AM.

June 20th, 2007, 09:30 AM	#34
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,487	No problem. I understand Finnglish (USA style) and have been known to speak a bit myself. __________________ dpalomaki@dspalomaki.com

June 24th, 2007, 07:44 PM	#41
Dan Herrmann Regular Crew Join Date: Oct 2006 Location: villa park CA Posts: 81	Method for removing noise Removing hum and noise from audio tracks How many times have you shot that perfect clip only to notice that you hear a computer whirr or refrigerator fan in the background? Or even worse, during some very introspective and moody dialog, you're distracted by a 60- (or 50-) cycle hum from improperly grounded equipment that made it onto tape. It's a well-accepted maxim that even the most professionally shot video can be ruined by poor audio, so let's look at some ways you can address noisy hums and buzzes in your audio tracks. Ducking levels If there's little dialog or required audio, then you can often get by with ducking the levels (aka hiding the nasty bits) during periods of silence. Use the mixer and automation to simply lower the track volume between words and speakers, and then raise it again when there's dialog. Since the noise you're ducking will still be audible during the dialog—you're just taking attention way from it during periods of silence—it could sound strange to hear the noisy hum return when people are talking. In these cases, try leaving a little bit of the noise in the silent/non-speaking parts of the clip. Alternatively, if you can record clean audio with another device from another, quieter location, you can mix that into the silent parts to help take attention away from the ducking. Parametric equalizers The audio spectrum, from the lowest bass frequencies to the highest treble frequencies, is represented in Hertz (Hz). The human voice tends to fall between 85Hz for a low bass and 255Hz for sopranos, while music instruments fall both below and well above this range. Equalizers are simply tools that allow you either to raise or lower the volume of specific frequency ranges while not affecting others, exaggerating—or removing entirely—certain ranges of frequencies. Most audio applications include some form of parametric equalizer—as an audio effect, plug-in, or feature. But if you're not an audio engineer or well versed in sound reinforcement, they're not very intuitive. Fortunately, there's not much to them at their roots. Basic parametric equalizer in Adobe Audition A parametric equalizer simply lets you specify a range of frequencies and either raise or lower the volume of tones that fall within that range. In Adobe Audition® the controls of the parametric equalizer are as follows: Frequency: the target frequency Amplitude (or gain): the amount you'll cut or boost the selected frequency Width (or Q): the width of frequencies that will be affected around your target Note: Although the terminology used in your software or hardware unit of choice may be different, these three functions are essentially what define a parametric equalizer. Some cheaper/lower-quality parametric equalizers do not include a manual width control, however. In Adobe Premiere® Pro, the Parametric Equalizer plug-in is actually a group of parametric equalizers that you can turn on or off selectively, to affect not just one particular frequency but up to five frequencies at the same time. In this case, we want to lower the volume of a single frequency, say the whirr of a computer's cooling fan: Enable the Parametric Equalizer and, next to the Frequency Bands, click the Band 1 check box (make sure the others are unchecked). Find both a spot in your audio track that's mostly silence and a prominent amount of the noise that you want to remove. Set the Parametric Equalizer controls as follows: Q/Width control to 100 (so the equalizer will focus on a very narrow range of frequencies) Amplitude control to roughly 75% of its highest value Click the Preview button to play the audio file, and then sweep the Frequency Band 1 slider repeatedly from its highest to lowest range and back again. As you do this, at some point you'll notice the fan noise that you're trying to remove jumping out in the mix and getting quite loud. This means you've found the target frequency. Pull the Band 1 Amplitude slider down carefully until the fan noise stops offending you. Watch the main graph closely, too; if you push the amplitude up or down too far, you'll notice it has a bell-curve effect on frequencies around it. Make sure to keep that spike as narrow as possible so that you remove only the tones you don't want. You can fine-tune things by slightly adjusting the Q/Width control, to make sure you're removing only the tones you don't want, and by slightly adjusting the Frequency control, to make sure you're dead-center on the offending fan noise. With Audition's five-band parametric, you can work on up to five different problem frequencies. Just watch the graph and make sure that closely adjacent equalizer peaks don't collide and affect surrounding tones more than necessary. Always keep in mind that you're cutting out frequencies with this technique, so be sparing with both the Amplitude and Width/Q controls—and be prepared to make some compromises to get the best overall results. There's no substitute for cleanly recorded audio, and any trick like this that attempts to clean things up after the fact will be inherently destructive in nature. Use it cautiously, and let your ear be the final judge.

June 26th, 2007, 07:28 AM	#42
Urban Skargren Major Player Join Date: May 2007 Location: Medellin, Colombia Posts: 225	Thanks, Dan, for your contribution. David: I noticed that on my camera the zoom noise differs with different zoom settings. Setting zoom to constant and using the wheel to adjust the speed I found that some speeds have lesser noise than others. Don't know if that's so on yours also. Some more links I found about shock mounts: http://www.thej-rod.com/ http://www.dvinfo.net/conf/showthrea...862#post596862 http://www.dvinfo.net/conf/showthread.php?p=595710 Others: are your zoom motors also audible? (Michael Y Wong is also complaining about this in the thread above) Last edited by Urban Skargren; June 27th, 2007 at 01:28 AM.

January 26th, 2008, 01:59 PM	#43
Pavel Tomanec Regular Crew Join Date: Jul 2007 Location: Oxford (UK) and Vrindavana (India) Posts: 118	Zoom noise Hi All, I must admit the zoom noise on my A1 Pal was also bad, I use AKG Blue line mikes. I have removed the Canon mike holder from the camera completely and got decent Rode shock mount. Since then the noise is gone from the recording and also from the headphones when monitoring sound. Shooting with the shock mount makes really big difference, I would highly recommend this to anyone concerned about the sound. Regards, Pavel Last edited by Pavel Tomanec; January 26th, 2008 at 02:01 PM. Reason: Grammar

June 21st, 2007, 11:10 AM	#35
David McGiffert Regular Crew Join Date: Feb 2007 Location: Topanga, CA Posts: 139	I just read this thread carefully. I DEFINITELY have SERIOUS zoom-motor noise that is picked up on my Sennheiser ME 66. It doesn't matter whether it's quiet or loud in the ambient, and it makes no difference having AGC off. I have tried loosening/tightening the mount holding the mic with no change. I have moved the position of the mic around, no change. My kids DV camera (Sony), using the same microphone, has zero-none-nada zoom-motor sound. Actually I have never had this problem on the other three DV camera's I've owned. I love this camera. This is not whining. But it is inexcusable to have this much noise transmitted to a microphone on ANY camera much less on a high-end beautifully-done camera like this one. I am totally open to being wrong about this and would love to hear what else I can try to solve what, for me, is a critical flaw in this camera. I know I can probably clean it up with software in post. But that is a weak solution. David

June 21st, 2007, 11:18 AM	#36
Urban Skargren Major Player Join Date: May 2007 Location: Medellin, Colombia Posts: 225	Do you use a rubber suspension or the mount on the camera?

June 21st, 2007, 11:27 AM	#37
David McGiffert Regular Crew Join Date: Feb 2007 Location: Topanga, CA Posts: 139	I am using the mic holder supplied with the camera. A rubber suspension set-up would probably be better (haven't tried it), granted, there is precious little space around camera to get to the controls using the supplied mic holder as it is. With a bulkier suspension set up it will be really crowded around the controls. But that might be the best solution. Thank you. David

June 21st, 2007, 12:37 PM	#38
Urban Skargren Major Player Join Date: May 2007 Location: Medellin, Colombia Posts: 225	If you hold the shotgun next to the camera pointing in the shooting direction and listen with headphones you should be able to find how far away the mic needs to go, if the problem is acoustic. I suppose there are always solutions with specially-built longer holders if needed. (you could even have a Z-shaped extendable arrangement built from a desk lamp holder...) If the problem is internal vibrations I really think a supension should do it. Don't know if this will help you: http://www.dvinfo.net/conf/showthrea...ght=suspension http://www.samys.com/product_detail.php?item=9026 http://www.bhphotovideo.com/c/shop/8...hoe_Clips.html There's probably a lot more said abot this here if you search on "suspension" either in this forum or the whole site.

June 21st, 2007, 11:23 PM	#39
David McGiffert Regular Crew Join Date: Feb 2007 Location: Topanga, CA Posts: 139	Hi Urban, I am going to try one of the shockmounts you gave me the tip on (one of the low cost ones from the B&H url). Thanks, I guess it's the only way to solve it. David

June 22nd, 2007, 01:15 AM	#40
Bill Watson Major Player Join Date: May 2007 Location: Noosa Queensland Australia Posts: 248	I can't hear any zoom motor noise on my XH-A1 at all.

January 26th, 2008, 05:24 PM	#44
Pavel Sedlak Major Player Join Date: Feb 2007 Location: Prague Czech Republic Posts: 263	try this way of mount There is no zoom noise. Attached Thumbnails

June 12th, 2009, 02:29 PM	#45
Geoffrey Cox Major Player Join Date: Aug 2008 Location: Huddersfield, UK Posts: 469	Thanks Pavel. I had lots of problems with motor hum and your set-up inspired me. I bought the Rode SM5 shockmount (which looks like the one you've got) and it works plus it simply slots into the A1's holder. Hum gone. It's cheap too!

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