Luna breakout box question

[Lotuz]

I feel like a noob asking this, but let's put shame aside.

Input LEDs 1-8: These LEDs indicate input signal level for each of the eight channels.

The three colors indicate levels as follows:

Green: -60 dBFs
Yellow: -12 dBFs
Red: - 1 dBFs

Ideally, input levels should be set so that the yellow LED lights occasionally, the red LED seldom or never.

I'm having a bit of trouble understanding why I need to turn down the output level of the "audio source" so much to avoid the yellow LEDs from lighting up more than just occasionally. I mean turning down the output level that much also means the level of the recorded audio is pretty low. Of course you can normalize after recording, but that also raises the noise level.

For example I've connected the output of the onboard soundcard of my multimedia pc to the inputs of the Luna breakout box of my other pc (see specs in my signature). I'm playing a CD with the Windows Media Player and I have turned down the volume to 21 (max volume is 100). The meters of the STM 1632 reach about -8, so shouldn't I be able to raise the output level a lot to get closer to 0 dB? But if I raise the volume of the WMP to about 66, then the yellow LEDs are lighting up almost constantly. The recorded audio seems fine though.

Were Creamware being a bit too cautious with that "occasionally"? Will I be fine as long as I avoid the red LEDs from lighting up?

[Fluxpod]

Just raise it.I wouldnt worry about the leds too much.If it sounds good its just fine.

[garyb]

yes, you're fine as long as you don't pass 0db.

the levels don't need to be pegged if you are working in 24bit, as you still get good bit depth about halfway up the scale. with analog, you really needed to peg the meter to avoid noise. there should be much less noise with a digital system, so if you're really having a problem with s/n, i'd check the system before the converter.

Fluxpod hit the number one rule of audio....

[Tau]

If Red = -1dBFS, then it's still below clipping level. Should be OK if it lights up occasionally and briefly.

[Lotuz]

Thanks guys!

Rule #1:
If it sounds good its just fine.

[garyb]

[ChampionSound]

When I use the Luna I/O box, I try to reach the level where the yellow LED is lit most of the time.
If only the green LED is lit and nothing else, I think the S/N ratio will not be optimal yet.