Dynamic Range Control actually compresses the peak of the waveforms, so that things like explosions, bass hits and effects are quieter than normal. The idea is to present good vocal dialog but without really loud sound during intense scenes (such as a "TV night time mode" when everyone else is sleeping, lol). This can actually affect music playback as well.
Yes, I connected only the stereo not the surround outs. And only my preamp not the power amp has attenuators, which, with the JVC player I almost never had to turn any higher or lower. Regarding DRC I don't recall it making much of a difference either on or off with the "Bad Day at Black Rock" DVD; both the music and dialogue levels seemed too low. But I will compare the audio again on this disc with DRC on & off.
I did turn volume to 100%; no help. Neither did turning off Dynamic range control.
Next I will go into speaker config settings and look what levels they are even though the manual says on p.17 "
"The STEREO AUDIO OUT terminals automatically down-mix the multi-channel audio source into the stereo signals. However, STEREO AUDIO OUT will NOT be affected by the “Down mix” modes and other speaker settings in the Audio Processing of Setup Menu (described in the page 68)."
If n/g, then as someone at AVS and Steve Hoffman suggested, it’s possible that in order to prevent overloading the stereo outputs by the 7.1 surround sound analog outputs, that rather than appropriately buffering (isolating) the stereo outputs Oppo instead applied some overall gain reduction to them. Thus, I will try connecting the front surround sound speaker pair and then go into settings and enable downmix and see if that stereo pair will give me higher output voltage.
As for mods, AFAIK there were none. I will ask the ebay seller about that. I have to get in touch with him and ebay anyway because the player was advertised as region free. But it’s not as it won’t play this "all zone" PAL-encoded DVD from South Africa. https://raru.co.za/movies-tv/37567-ride-the-high-wind-dvd The image rolls and is monochrome not in color.
And the player gives and "Invalid Region Code" message when loading this DVD set from the Netherlands .
So I will be asking for reimbursement to purchase a mod kit like this.
Also, is the Oppo modified? I own a modified Oppo that I rarely ever used anymore. If I recall correctly, the max output was greatly reduced due to the mods. Seems to me the out was max'd at about 1v, not the typical 2v.
Success, well at least mostly. Perhaps the problem was an Oppo 95 design difficulty in preventing gain interactions between the stereo outputs and the surround outputs. But then my old JVC DVD player has 5.1 outputs and yet the stereo outputs apparently have substantially more output voltage than the Oppo 95’s. OTOH, both the Oppo and JVC stereo outputs are within 0.2V, so all I can think of is an impedance mismatch.
In any case, to use the 95’s front L & R outputs, I had to configure the speaker set up like I had a 5.1 system so that I could disable downmix mode. That allowed me to boost the output level of front speakers, which I had to go more than 7db to get about the same volume as I got from the stereo outputs of the JVC player-when playing the “Bad Day at Black Rock” DVD.https://www.amazon.com/Treatment-Season-1-Gabriel-Byrne/dp/B0013FSL0C/ref=sr_1_2?crid=21KTXYGT01BCU&keywords=in+treatment+season+1+dvd&qid=1580103280&s=movies-tv&sprefix=In+Treatment%3A+Season+1+%2Cmovies-tv%2C209&sr=1-2
there was no dialogue track, just music. Apparently, 5.1 Dolby surround is not a locked down mix format.
So I had to reset the speaker config back to downmix mode (but this time I selected LT/RT instead of stereo, otherwise speaker level adjusting would be disabled). That restored the dialogue track. Then I compared the sound of the LT/RT and stereo downmix modes. There was a slight differences; in one mode the voices seemed slightly more forward and/or narrowly focused, the mode had the voices more broadly space across the sound stage. I also noticed that one mode had noticeable background noise or hiss; likely due to the speaker levels being tweaked to 10db.
Again, my trusty JVC DVD player from 2004 had no such issues. Very odd.
I also noticed that the "In Treatment" DVD set seemed to have higher overall output on the Oppo 95 than when playing the "Black Rock" DVD. Same seemed also to be true of this DVD series. https://www.amazon.com/Enlightened-Season-1-Laura-Dern/dp/B004EPYZCQ/ref=sr_1_3?crid=2GRWNFK87LYU8&keywords=enlightened+season+1&qid=1580230839&s=movies-tv&sprefix=enligh%2Cmovies-tv%2C133&sr=1-3
It's really bad that there's apparently no standard levels for 5.1 and/or stereo mixes on DVD and/or BD.
Anyway, thanks for getting me back some respectable stereo output level, whatever the actual cause was.Oops! I forgot to ask the seller if he had the player modded in any way. Will do so now.