Topic: Oppo "high rez" output

[Nick's Picks]

so if this can be done via HDMI...I should build a cable that is HDMI > SPDIF
hmmm...

just thinking outloud

[Jammin72]

Is that even possible?  I'm not up on how that works bout wouldn't you need some sort of converter?  Great Idea though if it's not terribly expensive to create.

[Nick's Picks]

I dont think so.
the hdmi interface is just a bunch of pins that carry data.  some pins are responsible for s/pdif, and that would be the pins you'd make the cable hook up to.

I bet it would work.

[scb]

http://electronics.howstuffworks.com/hdmi2.htm

[RebelRebel]

http://www.gefen.com/pdf/EXT-HOMETS.pdf

http://www.gefen.com/kvm/product.jsp?prod_id=4174

just study one of these and reverse engineer it for the masses.

[Evil Taper]

There's no advantage of running HDMI output and then bumping it down to SPDIF.  They're both digital source so HDMI isn't any "higher rez" than SPDIF when talking about audio.  It'd basically just be a way of transmitting a digital signal through different connectors.  If you need more than 2 channels use ADAT.  If you want "higher quality" use AES/EBU digital which uses XLRs, it's considered to be professional while SPDIF isn't.

Nick....why?  What are you trying to hookup that you can't hook up any other way?  Is there some audio gear with HDMI now?

SPDIF - 2 channels of digital audio only
HDMI - multi channel digital audio plus ultra hi rez video

[Evil Taper]

Now I understand, you're talking about that Oppo player.

You can only use the HDMI for digital surround output (assuming that your receiver has an input).  Otherwise all the 2 channel audio will be the same whether it's being delivered with SPDIF or HDMI.

[Nick's Picks]

oh?  sure about that?
that is what we are trying to determine.  the manual states "high rez" output via hdmi, and that the s/pdif outputs are dumbed down.  maybe the hdmi output isn't.

[janka]

Nick where does it state the HDMI is High Rez and the spdif is dumbed down? I looked at the pdf manual on page 31 sec 8 it states "digital audio output via HDMI will be the same as the SPDIF output"

[Evil Taper]

Well how exactly would it be different at all?  A cd is digital audio, a dvd is digital audio, dsd is digital audio...the outputs are just transmitting a digital signal to your amp.  I don't see why there would be a DAC>ADC step going on within the player itself unless there's a channel summing for surround to stereo that happens in front of the SPDIF output.  I don't imagine there's anything of that nature going on since there's a multichannel digital output via HDMI.  There's a DAC in front of the analog outputs, possibly a summing amp also to resolve to 2 tracks, and POSSIBLY the SPDIF incorporates an ADC post summing amp to output a digital stereo signal.  That seems like an awful lot of needless converting going on but who knows what the designers did.  What you should do is play a surround formated disc and then output only with the SPDIF to see if there's a summed stereo output of all channels or only 2 channels of the mix being output.

[Nick's Picks]

I thought that there had been discussion about this all ready once we found that the s/pdif "dumbs down" its output ..., but the signal was preserved on the HDMI. guess not ?
one less thing to ponder.

[Evil Taper]

Well some less professional SPDIF interfaces only accept 20 bits of data but anything made recently that's an audiophile type device should be capable of 24 bit SPDIF.  Look in your manual.

[RebelRebel]

The spdif is dumbed down due to lack of protection schemes in the spdif protocol. This is what Oppo has said directly in multiple calls to them. From my understanding, your own high resolution recordings (IE not commercially produced) will be fine as there is no copy protection stumbling block, but commercial recordings(high res commercial recordings) will not work on the OPPO spdif output.

oh?  sure about that?
that is what we are trying to determine.  the manual states "high rez" output via hdmi, and that the s/pdif outputs are dumbed down.  maybe the hdmi output isn't.

[Evil Taper]

Well what's the advantage to running a digital source out of this player versus any other player you have or your PC even?  It's all digital either way.

[RebelRebel]

the quality of conversion/outputs varies wildly amongst players. Or so ive heard.

Well what's the advantage to running a digital source out of this player versus any other player you have or your PC even?  It's all digital either way.