Getting proper audio levels in SF -Sound Forge - PC

Subject:Getting proper audio levels in SF Posted by: JHebert Date:8/26/2002 8:02:56 PM I'm not sure if I'm getting proper audio levels in SF. I have two related questions that seem to indicate something's up, but I not sure what. My equipment setup is relatively simple, run through a Mackie 1202 VLZ Pro mixer: input source 1 EV RE20 mic input source 2 Horita NTSC Test Signal Generator (with 1KHz 0dB audio tone output) computer sound card CardDeluxe (24/96 Audio Card) The Mackie is outputting a +4 signal via the ALT3/4 outputs (1/4") to the sound card, which is set for +4 balanced input (on 1/4" also). Here's where I'm having problems: I send the tone into input 2. I set input 2's Gain pot and the Main Mix pot both at Unity. Then I bring up the input 2 preamp (trim pot) until the mixer's LEDs light up at 0db. (I have also sent tone into a line input and then used that input's Gain pot to get to 0db, however the overall result is the same problem I now have). Now, opening Sound Forge's record panel, I see that the input level is showing steady at -18.2. To me, this seems low. There is no allowance for gaining up the CardDeluxe, so it appears my only option is to boost the output of the Mackie. Trying to do so however overloads the Mackie before I hit 0 on SF's record meter. The second issue is related to the first... and may be exactly the same except it involves activ recording rather than just signals. In this case, when I try to record narration with the RE20, I have to set the input Trim, the Gain, and the Main out to about 3 o'clock (about 3/4 of their full range) just to get a signal that peaks around -12dB in SF (I am approximately 8 inches from the mic, and speaking more forcefully than usual). However, this high a level also increases background noise and electronic noise, leaving me with an undesirable recording. I'm not sure what's up. I've been going around with this for a week... It seems to me that I should be getting strong signal all around. I'm using equipment that checks out (EV checked the mic, and my local shop and I verified the mixer), along with properly wired balanced cable (also double-checked). I keep thinking the mixer's got to be the problem, outputting weak signal, but it checked out against the store demo in every test we put it through. I'd appreciate any help, tips, or questions you could post to help me troubleshoot this. Thank you, James
Subject:RE: Getting proper audio levels in SF Reply by: rraud Date:8/26/2002 8:59:41 PM I'm sure something is not set correctly, so I would not bother trying to compensate by setting abnormal levels, ect. Make sure the correct sound card and inputs are selected. Options>Preferences>Wave menu. Are your cables okay? Check the basics. Sometimes we just assume it's complex.
Subject:RE: Getting proper audio levels in SF Reply by: JHebert Date:8/26/2002 9:42:03 PM Thanks for your ideas... I agree with you that it seems something simple must be tweaked somewhere. But what? I keep looking. The audio card is properly selected in XP. There is no other audio device in this system, so all audio must go through the sound card. The Windows audio mixer panel is therefore not available, since the one that belongs to the Card Deluxe is now running things. FYI, I have read that analog audio tone signals in digital gear should read anywhere from -22 to -16, since digital needs the headroom to handle peaks, so I would venture to guess that my tone settings show things correctly. However, with regard to my mic levels being low... well, what do you folks get for audio level peaks when you record narration? Double-checked cabling... nothing new to discover there. Cables from mic-to-mixer are XLR (balanced). Cables from Mackie to soundcard are XLR-to-1/4 (balanced). Soundcard to powered speakers are 1/4" unbalanced (using balanced made no difference there). Still looking, and still inviting replies! ;-) James
Subject:RE: Getting proper audio levels in SF Reply by: JonnyD Date:8/27/2002 1:47:58 PM Hey James, I'm only using 4.5, but I never go any hotter than -18. I need the headroom. That's from 6 years of expierence in a V/O studio. Good Luck! John
Subject:RE: Getting proper audio levels in SF Reply by: rraud Date:8/27/2002 2:02:53 PM The -22 to -16 you are referring to, is known as "digital zero" But it varies slighty. Panisonic DATs use -18dbfs (decibels @ full scale digital) as digital zero. Digital VTRs are usually -20 and this is what the networks specify. On program material as long as you don't exceed 0dbfs and clip, your okay. I generally record VOs peaking around -4 to -6dbfs. Give yourself enough headroom, but of coarse this varies with narrators.. some are consistant, some are not and they will need more headroom in case they unexpectedly get excited. I also like to run the voice though a good outboard compressor before the sound card, and do the final processing in post.

Subject:Getting proper audio levels in SF

Posted by: JHebert

Date:8/26/2002 8:02:56 PM

I'm not sure if I'm getting proper audio levels in SF. I have two related questions that seem to indicate something's up, but I not sure what. My equipment setup is relatively simple, run through a Mackie 1202 VLZ Pro mixer:

input source 1
EV RE20 mic

input source 2
Horita NTSC Test Signal Generator (with 1KHz 0dB audio tone output)

computer sound card
CardDeluxe (24/96 Audio Card)

The Mackie is outputting a +4 signal via the ALT3/4 outputs (1/4") to the sound card, which is set for +4 balanced input (on 1/4" also).

Here's where I'm having problems:

I send the tone into input 2. I set input 2's Gain pot and the Main Mix pot both at Unity. Then I bring up the input 2 preamp (trim pot) until the mixer's LEDs light up at 0db. (I have also sent tone into a line input and then used that input's Gain pot to get to 0db, however the overall result is the same problem I now have). Now, opening Sound Forge's record panel, I see that the input level is showing steady at -18.2.

To me, this seems low.

There is no allowance for gaining up the CardDeluxe, so it appears my only option is to boost the output of the Mackie. Trying to do so however overloads the Mackie before I hit 0 on SF's record meter.

The second issue is related to the first... and may be exactly the same except it involves activ recording rather than just signals. In this case, when I try to record narration with the RE20, I have to set the input Trim, the Gain, and the Main out to about 3 o'clock (about 3/4 of their full range) just to get a signal that peaks around -12dB in SF (I am approximately 8 inches from the mic, and speaking more forcefully than usual). However, this high a level also increases background noise and electronic noise, leaving me with an undesirable recording.

I'm not sure what's up. I've been going around with this for a week... It seems to me that I should be getting strong signal all around. I'm using equipment that checks out (EV checked the mic, and my local shop and I verified the mixer), along with properly wired balanced cable (also double-checked). I keep thinking the mixer's got to be the problem, outputting weak signal, but it checked out against the store demo in every test we put it through.

I'd appreciate any help, tips, or questions you could post to help me troubleshoot this.

Thank you,

James

Subject:RE: Getting proper audio levels in SF

Reply by: rraud

Date:8/26/2002 8:59:41 PM

I'm sure something is not set correctly, so I would not bother trying to compensate by setting abnormal levels, ect. Make sure the correct sound card and inputs are selected. Options>Preferences>Wave menu.
Are your cables okay? Check the basics. Sometimes we just assume it's complex.

Subject:RE: Getting proper audio levels in SF

Reply by: JHebert

Date:8/26/2002 9:42:03 PM

Thanks for your ideas... I agree with you that it seems something simple must be tweaked somewhere. But what? I keep looking.

The audio card is properly selected in XP. There is no other audio device in this system, so all audio must go through the sound card. The Windows audio mixer panel is therefore not available, since the one that belongs to the Card Deluxe is now running things.

FYI, I have read that analog audio tone signals in digital gear should read anywhere from -22 to -16, since digital needs the headroom to handle peaks, so I would venture to guess that my tone settings show things correctly.

However, with regard to my mic levels being low... well, what do you folks get for audio level peaks when you record narration?

Double-checked cabling... nothing new to discover there. Cables from mic-to-mixer are XLR (balanced). Cables from Mackie to soundcard are XLR-to-1/4 (balanced). Soundcard to powered speakers are 1/4" unbalanced (using balanced made no difference there).

Still looking, and still inviting replies! ;-)

James

Subject:RE: Getting proper audio levels in SF

Reply by: JonnyD

Date:8/27/2002 1:47:58 PM

Hey James,

I'm only using 4.5, but I never go any hotter than -18. I need the headroom. That's from 6 years of expierence in a V/O studio.

Good Luck!

John

Subject:RE: Getting proper audio levels in SF

Reply by: rraud

Date:8/27/2002 2:02:53 PM

The -22 to -16 you are referring to, is known as "digital zero" But it varies slighty. Panisonic DATs use -18dbfs (decibels @ full scale digital) as digital zero. Digital VTRs are usually -20 and this is what the networks specify. On program material as long as you don't exceed 0dbfs and clip, your okay.
I generally record VOs peaking around -4 to -6dbfs. Give yourself enough headroom, but of coarse this varies with narrators.. some are consistant, some are not and they will need more headroom in case they unexpectedly get excited. I also like to run the voice though a good outboard compressor before the sound card, and do the final processing in post.