View Full Version : firewire audio levels


Nicholi Brossia
July 31st, 2003, 08:43 PM
I have a few projects recorded on dvcam and would like to transfer those to minidv (my school uses sony, i have a canon). Today I used one of the school's sony camcorders as a source vtr and firewired into my gl2. The video turned out just fine, however the audio was severly over modulated. The levels on my gl2 were almost constantly past the limit. At first, of course, I blamed the school equipment and used an actual editing vtr as my source. The same thing happened. The only thing I could think of was to change the settings to audio att on, and audio dub in. Neither of those made a difference - i would imagine they refer to the a/v input and not the firewire.
So, to make a long question short... is there any way to regulate the firewire audio record level of the gl2?
Also, this is the first time I've tried dubbing to my gl2, does this happen often? or could it maybe be due to the different speed of dvcam?

thanks
nicholi

Mario Lauria
August 8th, 2003, 03:39 PM
Hello,

there's one thing missing in your post:
how is the SOURCE audio level?

Can you see the audio level on DVCAM vtr?

If the source audio level is normal, then there should not be any reason for the two levels to be different.

The signal is transmitted via firewire and received with the same standard on the other side.
So, unless there's something different between DVCAM and
mini DV, the two levels should be the same.

I don't think that the different speed has something to do with your problem.

As you mentioned, the attenuators on GL2 have effect only on audio inputs.

Anyway, as I don't know any hardware capable to modify the signal on firewire, you could do the following to solve the problem:

import the project in a PC using a video editor (i.e. Adobe Premiere), then modify the audio level and finally export the new obtained project to miniDV.

This should work fine if the original audio is not distorted.

Let me know....

Ciao

M. Lauria

Don Palomaki
August 8th, 2003, 04:33 PM
GL2 levels past the limit? What limit? How are you jduging the levels? If using earphones or analog output you may need to change the analog output level.

What gear were the original tapes made on.

To check levels, try firewire the tape back to the Sony gear and you should see the levels the same as the original. ALso, if you capture with an NLE you should be abel to judge the recorded level and see whether or not the waveform is distroted/clipped.

Nicholi Brossia
August 8th, 2003, 08:48 PM
Yeah, I actually feel pretty dumb. Yesterday, I almost drove myself crazy trying to fix the problem when it ended up being super high levels on the original tape. I'm guessing that firewire can't be regulated at all (through a mixer or something), and if it does I don't have the equipment, so I'm going to have to figure out some other way of getting the audio dubbed. The video looks good. At least I have that much.
I guess I was just making a mountain out of a mole hill.

Don Palomaki
August 9th, 2003, 05:55 AM
The Videonics MXProDV video mixer with Firewire I/O may allow adjustment of audio levels.