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quote:
Originally posted by ZiKEThis difference is caused by different dB values used in iLive and computer recording programs. Remember, that dB is not an unit. It is only a suggestion, that measured values are shown logarythmically. iLive scale is just in dBs where 0dB on meter means +4dBu on output. It is scale typical for analog consoles. Maximum output level without distortion is about +22dBu, so it is 18dB on scale. Your computer shows values in dBFS (Full Scale) where 0 dBFS means the maximum value (which can not be exceeded in any way).
It means, that when you’re sending 0dB (dBFS) from your computer it is also a full signal in iLive, 18dB above 0 on meter. And when you’re sending 0dB from computer via S/PDIF you will get -18dBFS on your computers scale.
Of course real values can vary from those above, your recording program can show RMS value despite peak (few dB lower), I am also not sure is 0dB in iLive exactly +22dBu on output.
Please look for dB, dBu, dBV and dBFS.
Best regards,
ZiKETHERE IS NO JUSTICE, THERE IS ONLY ME
Thanks for that ZiKE. While I understand the differences in scales, I really don’t have a usable volume level at my computer from the iLive. It is quite um.. quiet. Even when I have every level control at full, I’m getting an audible, but not fully usable signal into my computer, yet every other S/PDIF piece of equipment I own will produce a full signal.
The reason this is such a big deal to me is that I am doing a live streaming broadcast and I was trying to keep it digital. It works fine if I use an analog output. I even tried running the S/PDIF output into my CD-recorder, with the same result. Two different recorders (one couldn’t work with the bitrate, and created a CD that sounds slow when played back, but still had the low levels). Since the iLive is the odd one out, then that’s what I’m looking at as part of the problem.
Brandon
Brandon Walls
Sound Engineer
First United Methodist Church
Cookeville, TN