More calibration findings - This should be useful information for anyone using Marantz or Denon Pre/Pros - and possibly others.
7.1ch inputs and LFE / Subwoofer Levels.
I reported a few pages back that when I was rough checking my calibration for the Oppo 7.1 outputs into my Marantz 7710, that the subwoofer level seemed to be very close to what it should be without adding 15 of boost or 10 or...why is it one or the other and when? Here's a good read to explain that:
http://www.avsforum.com/t/748147/lfe-subwoofers-and-interconnects-explained#post_8855640 - and it was really helpful.
And that article completely agreed with my need to bump the sub level from the Oppo up 5dB to fall into calibration based on my newly acquired Blu-ray calibration disc. I know, I said 5, but above it was 15 or 10. In truth,
it is 15, as Bob has said -
at least a few times. However, it depends on what your Pre/Pro is doing already as to how much you'll actually need to adjust.
The Marantz "Audio" menu has two places to look: "Audio/Surround Parameter/Low Frequency Effects Level" and "Audio/Subwoofer Level". This is initially confounding as there is only one input (SW) involved that is receiving both SUB+LFE from the Oppo; there is no discrete LFE analog input nor is there a discrete LFE output on the Oppo. So why two places to control the same thing? I have asked Marantz and if I get an answer I'll post it.
For my AV7701, it appears the default for LFE Level on the 7.1 inputs is 10. The choices are 0/5/10/15. This explains why my calibration was already fairly close - 10 of the 15dB I needed was added by default and that makes sense from the article above. But also, as the article above explains, when the Oppo does bass management and combines SUB+LFE, the right thing to do is attenuate that signal 5dB to prevent overload - and it does this, so that's why the additional 5dB is needed.
My Subwoofer Level was -9.5dB as set by Audyssey for all inputs - although each type input (7.1, HDMI, Analog, etc) appears to support is own independent setting.
I'm not sure where the best place to add the other 5dB is - or that it even matters, but for the moment, I'll do it on the LFE channel just to keep all of what Audyssey did consistent and to keep the settings simple to understand for later when I forget all of this.
Why am I not turning up the SubWoofer Amp as Bob suggested? Good question. If I do that, then for all other inputs, Audyssey will want to further attenuate the Subwoofer Level by 5dB, but it is already @ -9.5 and another 5dB would put it at -14.5; 2.5dB out of trim range (-12/+12). So it is not really possible to raise the volume of the Sub Amp and keep the rest of the calibration in place.
I hope this is helpful and not too redundant, but getting the bass right is the right thing to do.
