interesting...does this apply only to analog output or for use with dacs as well...
I can chime in here as I have quite a bit of experience with the Oppo in this regard. First I can confirm that this applies to the digital out as well. First you may not be able to 'bypass' volume control and thus the Oppo signal adjustments via the analog outputs. Jason was referring to digital output configuration, which is SPDIF -- the digital audio output protocol. For analog, you just want to 'minimize' the signal mods made by the Oppo using the last 2 suggestions from Jason, but likely not eliminating all mods to the original signal. You get great sound out the analog this way, trust me. I run my SACD's through these analog outputs, and it sounds great. More on digital output configurations I experimented with below, with my outboard DAC:
The "PCM" output is a form a direct digital output that will go out through the Toslink and the Coax digital out on the 970HD. In the audio setup section of the on-screen Oppo config, you will see this. PCM 192 is the highest setting. According to Oppo if you set it here, it will automatically downsample, to the lower sampling rates until it gets a signal lock at the highest available sample. But by going "RAW" you effectively disable this feature, as this will send true un-touched digital stream to the digital output. I have this digital out going straight to an external CIAudio DAC-2 in this regard. So in summary, yes it applies to the digital outs as well. In fact, if you have digital output set to PCM instead of RAW, then regardless of what other settings you have adjusted or turned off, your signal is being processed by the Oppo, it is not the original digital signal. You can find the RAW setting value in the
When playing SACD's I found that I had to use the analog front L/R outputs because the DAC doesn't convert the signal. According to Oppo, it converts the DSD signal to PCM then to analog. I could not get the PCM digital signal through digital out to my DAC, so I actually have two sets of outputs simulatenously connected out of the Oppo, one analog set, and one coax digital (spdif)
This works fine. I just switch to a different input on my P-8 to listen to SACD's and DVD's and another for listening to redbook via my outboard DAC. Its a nice way to go, to avoid cable swapping all the time.
I turn HDMI audio OFF because most of my listening is 2-channel, through my outboard DAC. I don't see the point of sending PCM audio down the HDMI cable to my HDTV only to route it back again through the DAC.
Most stereo DACs don't convert home theater 5.1 surround sound / Dolby DTS raw digital signals either. So its best to separate your 2-channel audio stream from your DVD HDMI if 2-channel audio optimization is your goal. So what this means is, you can't route a RAW digital signal from a standard DVD to a stereo DAC. It won't know what to do with the signal. I've tried it.
I should now preface that I am not a big surround sound person, I'm a 2-channel purist. I do not use a surround sound decoder, or any of that. That is why audio over HDMI is not necessary for me. I use HDMI only for the video signal, for watching DVDs. I route the audio from the DVD straight out the analog L/R front to my P-8. Therefore I leave HDMI audio set to OFF. If you left it on, then essentially are saying "send the digital audio signal to the TV, and then the TV will convert it to analog. I'd prefer to rely on the Oppo DAC in that case, versus an HDTV's audio DAC for 2-channel purposes only of course.
So in summary for 2-channel systems:
Use digital out, set SPDIF to RAW on Oppo 970HD
Coax is my preference output to an external DAC
If you don't have an external DAC in 2-channel then use front L/R (not mixed) all other speaker channels off.
SACD: ditto, via analog outputs
DVD w/ 2channel audio: HDMI for video, and audio out via analog outputs used for SACD for convenience of setup. [ Alternatively you can enable PCM 192 for this setup and get digital output to an external DAC, but its a pain to keep changing this Oppo config just to play a DVD, I like the analog outs for DVD in 2-channel, Oppo does a fine job there ]
DVD w/ surround sound systems: Use HDMI for video and audio with your surround decoder/receiver.
Ok, back to my SACD listening session!