Output issue from DS DAC


#1

I hope that is something simple and I’m having a senior moment. It began when I noticed that the bluray playback resolution was not too remarkable ( 48 k, 16 bit); I was inputting my Oppo 105 via d60 coax to ds dac. Thinking that the limitation was do the coaxial, I tried to adjust the Oppo audio settings but nothing improved. I realized that I had to ratchet the volumn up to get adequate levels; knowing that this was futile attempt, I switched analog cables, nothing. I bypassed the dac altogether, connecting Oppo with rca analogs; the result was remarkable. I had to dial the volumn down significantly and I was getting the typical bluray resolution. I repeated using Xlr cables, even better results! To eliminate the problem with cables, I hooked the ds player to the pre using the coax eliminating the dac; same remarkable results. I have not updated the software. Maybe I haven’t set this up correctly or missed a setting.
Also, is there a i2s to regular HDMI adapter? Thanks


#2

I having the dac outputs going into a Nad m12 pre. Would there be an incompatibility issue between these 2 units?


#3

DVDs, DVD-As and Blueray disks can limit the digital output sample rate to 48kHz. It’s a part of the Digital Rights Management (DRM) that’s designed into them. Not all limit the output sample rate, but many popular ones do. (SACD has a similar limit: no raw DSD bits are allowed outside a unit.)

Even so setting an Oppo up correctly to get the maximum resolution on the digital outs isn’t simple. There are some posts around here that talk about it: Among other useful posts I remember some by tarnishedears in the “Getting Oppo DSD Output to the Direct Stream Dac” thread. Here’s one but perhaps reading more of the thread might be helpful.

https://forum.psaudio.com/t/getting-oppo-dsd-output-to-the-direct-stream-dac/2744/115 (you might need to scroll up to the top of that post.)

There isn’t a simple (passive or direct wire to wire) adapter from I2S to HDMI, there are various HDMI to I2S things with processors (or at least specialized chips) available, but, in general commercially built and sold ones won’t defeat the DRM mentioned above - HDMI was designed with DRM in mind.


#4

Thanks Ted for your response; ill try again tweeking the Oppo. I’m more concerned about the lower output when using the dsdac. Is there any gain settings that I should be looking at? When I bypassed the dac, the outputs from both the ds player and Oppo were substantial; by my estimate at least 25-30 %.


#5

The DS is indeed a little quieter at max volume, about 3dB. That shouldn’t be substantial, but it is there. Is there a chance that you have the DS’s outputs set to LOW? If you don’t know, the easiest thing to do is turn the volume down a little on the DS, then press the “DAC Level” button on your remote. It will either make the DS 20dB louder or 20dB softer. You’ll get about 6dB more by using XLR audio interconnects compared to using RCA.


#6

There was a bump when I hit the filter key. I had the dac’s output at about 65; without touching the preamp setting, i maxed the dac output and it was still a significant difference when compared to oppo’s output directly into preamp using single ended. I’m using balanced inputs for dac. What is the normal acceptable output setting for the Dac? Will running at higher setting( I currently running 85 with a good bump on the preamp? At a higher range will problems of distortion occur? I don’t understand why the Oppo output is so much greater than the dac. Thanks for helping


#7

FWIW - On my remote that button is unintuitively labeled “Filter” rather than “DAC Level”.


#8

(I highly suspected that angela222 had a more current remote.)


#9

There’s no reason to not turn up the DAC to 100 (except if you get some crackles on SACDs in Redcloud.) There is a bit of compression of loud material at a volume level of 106 (which you can only get to with the DS output level set to low.)