sjkartchner wrote:1961TC4ME wrote:One thing I've noticed, and I don't know if this is inherent to the unit I bought or to S/PDIF in general, but the out coming signal from the converter is a bit weak (i.e., not nearly as hot) compared to the other regular analog outputs (channels 1-8) which required me to raise the db output for the 2 channels (9 & 10) in the audio output section of Hauptwerk. I had to bump channels 9-10 up to +8 to get a sufficient signal, simple enough to do and it now works well.
Marc
Output levels differ significantly between professional and consumer protocols, and S/PDIF is definitely a consumer protocol. See this article for a good explanation: http://www.harmoniccycle.com/hc/music-26-+4dBu-10dBV.htm.
So, if you have a somewhat higher end audio interface such as an RME or MOTU, even though the analog audio outputs will be at a professional level, the S/PDIF output (pre-conversion) will still be at a consumer level. As noted at the link, the difference in levels between the two is significant.
Here is a link that explains how the S/PDIF consumer digital protocol differs from the AES/EBU professional digital protocol: http://www.rane.com/note149.html.
P.S. Don’t get lost in the tall weeds of trying to figure out how the digital protocols compare with the analog protocols — the level differences between the two (professional vs. consumer) in either domain is the central point to be appreciated.
OK, this brings up a question after I decided to investigate. I've known all along that my 1010LT has two selections for the S/PDIF which can be chosen by ticking one box or the other, 'consumer' and 'professional.' It has been set to 'professional' since day one. Selecting either choice makes zero difference in the sound or the audio output level to channels 9-10 which on the 1010LT is the S/PDIF channels. Am I missing something here?
Marc