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GeekNews
08-09-2011, 03:25 PM
Has anyone figured out how to get the audio levels up in the SDI output. It appears to be running 17db less than where it should be. I have no idea how to get the levels higher.

The video/audio capture device I am recording to has no way to increase the audio levels and even though I have everything balanced the SDI Audio is simply 17db to low out of the 850?

Anyone have any ideas on what I can do to rectify this?

GaryG
08-09-2011, 05:39 PM
This and the scopes not being calibrated accurately are the two current "errors" in the Tricaster, as far as I can find.

Voltage references are for analog audio. NOT for digital. A SDI audio input leveled to 0db, with the mains leveled to 0dB, should come out of the SDI output at 0dB.

The output stage pad makes no sense for digital audio. I've mentioned elsewhere that I suspect this was put in to bring the analog outputs to some voltage scale standard*. Affecting the digital output in the same way is a mistake. Digital signals should be clipped at 0db on the meters.

One should not have to clip the internal buses in order to get the same level of audio on the output as was fed to the input. Negative gain through an audio system isn't right.

vanderwielen
08-10-2011, 06:32 AM
can you describe how you determined the 17db offset?

pdxJoe
08-10-2011, 09:46 AM
This impacts me as well. SDI audio output is far too low no matter what device I send it to. I have an external recording deck and two different external encoders that all agree that the tricaster xd300 sdi audio output is too low.

Would love to hear how others are working around this issue.

Joe

GeekNews
08-10-2011, 03:10 PM
Pretty simple master audio recordings on the tricaster have a 17db delta as compared to SDI audio. It simply sucks big time.

The only thing we have been able to do this time is increase the audio levels 10db digitally in final editing. This obviously results in fantastic audio quality "gag"

This needs to be fixed.

TTFNTV
08-15-2011, 11:19 AM
Has Newtek indicated if this is going to be fixed?

Do wonder though why every 850 owner isnt complaining. Perhaps this is not a problem on all production units? Could this just be a problem with the GeekNews unit?

We were looking at an 850 but this would be a major problem for our proposed workflow, so doesn't look like a good option for us.

vanderwielen
08-15-2011, 01:22 PM
Not be stupid, but could you explain more? in my case, if set slate tone to 0db on an input..by setting the slider to 0db, it reflect as 0db on the master, when the master slider is set to 0db. If i route the slate to a second 850, it will always show as 0db when that slider is set to 0db and reflects as 0db on the master. if i take the output of the second 850 and send it to a ki-pro, sony 1500 make a recording and route it back to the first 850, i'm at 0db. I've also had several ENG and SAT trucks comment that they want my SDI audio to peak no higher than 3db above 0.

GaryG
08-16-2011, 04:00 PM
Not be stupid, but could you explain more? in my case, if set slate tone to 0db on an input..by setting the slider to 0db, it reflect as 0db on the master, when the master slider is set to 0db. If i route the slate to a second 850, it will always show as 0db when that slider is set to 0db and reflects as 0db on the master. if i take the output of the second 850 and send it to a ki-pro, sony 1500 make a recording and route it back to the first 850, i'm at 0db. I've also had several ENG and SAT trucks comment that they want my SDI audio to peak no higher than 3db above 0.

I'm going to backpedal a little here. I could have sworn we were having to deal with this problem, but I just fed the output of the tricaster back in to an input, and with everything dialed up to 0db, I was a perfect 0dB on the input.

So at this time, we do NOT appear to be able to confirm this problem.

GaryG
08-16-2011, 04:08 PM
Todd, will you give that a try? Run the 1k tone from a ddr, and bring the SDI output in on, say, input 1. You'll need to solo and mute so that you don't get internal feedback.

But if I put a tone at 0db on the DDR meter, it reads at 0db on the Master meter, and then when I bring it in on an input, it reads at 0db on that input, too.