GL2 sound distortion problems! at DVinfo.net

Dirk Goris · October 15th, 2002, 03:26 AM

Hi,

I've tried to connect a cd-payer, md and receiver to the mic-terminal (in camera mode) using a standard stereo adapter "1/8" stereo male plug to 2 RCA plugs". I've put the audio record level switch to " Manual" and turned on the "microphone attenuator" in the menu. Even with the audio levels almost completely turned down I get massive sound distortion.

I'm doing this test because I've been allowed to connect my camera to the soundboard(pa) during an upcoming concert.

Please tell me what I'm doing wrong.

Thanks,

Dirk

Edward Tune · October 15th, 2002, 05:10 AM

A 'mic' level (the output from a microphone) is a very low level thing... at best maybe a couple of millivolts and may be in the microvolt range.

A 'line' level (typical output of a CD player, MD, etc) is a high level device, usually in the 600 millivolt range.

You are driving your 'mic' inputs extremely hard, hence the distortion.

So the retorical question to you is: What kind of outputs does the mixing board have? Are they going to feed you the signal at line level or mic level? This question needs to be answered real early in the game or you will have problems!

Next question: What are you doing? Making a demo tape for a band or something? I ask because even though they will tell you "everyhing goes through the board" you will find that at least one member will run directly to his/her own amp and speakers and... very few 'mic' the drums... so you will end up with absolutely perfect audio from the mixer.... minus drums!

Really helps if you can sit in and observe a few sessions. Some mixer 'operators' like to run in the board in two stages... off and on.... You need to have a very good relationship with them so that they provide the levels you need... You do not want them thinking to themselves "Gee, the room just got noiser, so I need to turn the music up!" Now you 'mic' levels just doubled for no reason on your tape.

Very important to wear headsets while recording! What you hear is not what you get. You are listening to all that sound as it hits walls, the ceiling, the back of the room. It may sound perfect but that is not what is coming from the board. You are getting just the audio and it may not be good!

It really helps if you can get a headlock on the audio guy and beat the answers out of him. The day of the performance is three weeks too late.

Hope this makes some sense...

Regards:

Dirk Goris · October 15th, 2002, 05:30 AM

Hi,

Thank you for this complete reply.

Now it's starting to make sense.

They are going to feed me the line level outputs and it's a solo concert. One man and his guitar.

I'm going to shot footage so they can put it on their website and for private enjoyment.

Thanks again,

Dirk

PS: Maybe it's better to connect a DAT or MD recorder to the soundboard and mix it later in post-production with the footage.

Don Palomaki · October 15th, 2002, 07:54 PM

You also might be overloading the output of your audio source. THe input impedance of the GL mic jack are about 600 ohms. Many consumer audio output are designed for substantially higher impedance loads.

"Line Level" from many mixing boards is either going to be +4 dBU, nominally around 1.2 volts, or perhaps a -10 dBV if it is a consumer board, or if you are getting an unbalanced tape output feed.

Best to get with the sound person well in advance to test connecting to the board, so you have time to recover after you findout that your kit of connectors, cords, and adapters do not give the results you want.

Usng the DAT or MD makes sense, even if only as a backup for th sound.

October 15th, 2002, 03:26 AM	#1
Dirk Goris Regular Crew Join Date: Aug 2002 Location: Belgium Posts: 66	GL2 sound distortion problems! Hi, I've tried to connect a cd-payer, md and receiver to the mic-terminal (in camera mode) using a standard stereo adapter "1/8" stereo male plug to 2 RCA plugs". I've put the audio record level switch to " Manual" and turned on the "microphone attenuator" in the menu. Even with the audio levels almost completely turned down I get massive sound distortion. I'm doing this test because I've been allowed to connect my camera to the soundboard(pa) during an upcoming concert. Please tell me what I'm doing wrong. Thanks, Dirk

October 15th, 2002, 05:10 AM	#2
Edward Tune ottotune Join Date: Jun 2002 Location: LAs Vegas, Nevada Posts: 43	levels A 'mic' level (the output from a microphone) is a very low level thing... at best maybe a couple of millivolts and may be in the microvolt range. A 'line' level (typical output of a CD player, MD, etc) is a high level device, usually in the 600 millivolt range. You are driving your 'mic' inputs extremely hard, hence the distortion. So the retorical question to you is: What kind of outputs does the mixing board have? Are they going to feed you the signal at line level or mic level? This question needs to be answered real early in the game or you will have problems! Next question: What are you doing? Making a demo tape for a band or something? I ask because even though they will tell you "everyhing goes through the board" you will find that at least one member will run directly to his/her own amp and speakers and... very few 'mic' the drums... so you will end up with absolutely perfect audio from the mixer.... minus drums! Really helps if you can sit in and observe a few sessions. Some mixer 'operators' like to run in the board in two stages... off and on.... You need to have a very good relationship with them so that they provide the levels you need... You do not want them thinking to themselves "Gee, the room just got noiser, so I need to turn the music up!" Now you 'mic' levels just doubled for no reason on your tape. Very important to wear headsets while recording! What you hear is not what you get. You are listening to all that sound as it hits walls, the ceiling, the back of the room. It may sound perfect but that is not what is coming from the board. You are getting just the audio and it may not be good! It really helps if you can get a headlock on the audio guy and beat the answers out of him. The day of the performance is three weeks too late. Hope this makes some sense... Regards:

October 15th, 2002, 05:30 AM	#3
Dirk Goris Regular Crew Join Date: Aug 2002 Location: Belgium Posts: 66	Hi, Thank you for this complete reply. Now it's starting to make sense. They are going to feed me the line level outputs and it's a solo concert. One man and his guitar. I'm going to shot footage so they can put it on their website and for private enjoyment. Thanks again, Dirk PS: Maybe it's better to connect a DAT or MD recorder to the soundboard and mix it later in post-production with the footage.

October 15th, 2002, 07:54 PM	#4
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,488	You also might be overloading the output of your audio source. THe input impedance of the GL mic jack are about 600 ohms. Many consumer audio output are designed for substantially higher impedance loads. "Line Level" from many mixing boards is either going to be +4 dBU, nominally around 1.2 volts, or perhaps a -10 dBV if it is a consumer board, or if you are getting an unbalanced tape output feed. Best to get with the sound person well in advance to test connecting to the board, so you have time to recover after you findout that your kit of connectors, cords, and adapters do not give the results you want. Usng the DAT or MD makes sense, even if only as a backup for th sound.