Thoughts & Questions (HDMI vs. Analog)

[andres6]

I've experimented with HDMI multichannel audio and multichannel analog interconnects (RCA cables). All of my cable were of very high quality both digital and analog, so that cancels that out.

I found 6 channel analog to be noticeably superior in sound quality to HDMI for DVD-Audio playback (my receiver is HDMI 1.1 so SACD can't be compared in this way). At first, I attributed this to "digital and HDMI being good for video but bad for audio."

After doing more research, I think it may be that my Denon 3910's DAC's were kicking my HK AVR 745 DAC's asses.

Question: With my new OPPO-83SE (which seems to have kicked the Denon 3910 to the curb on improved sound quality), of course I'm using the multichannel analog outs because my AVR is "ancient" by manufacturer standards (and HDMI 1.1 ) Getting to my question.... if I set SACD output to DSD instead of PCM, am I bypassing the Oppo's superior DAC's in favor of the inferior one's in my receiver? If I choose PCM, am I getting all I paid for from the 83SE then?

This might all be moot, though, since my HK AVR745 has the ability to bass manage and equalize the multichannel inputs, which I do use it for since it has a good ability to do this well. (I can switch from 6/8 channel and 6/8 channel DIRECT - no AVR bass management and direct pristine pass through). However, as good as 6 or 8 channel direct mode is (bypassing any effect the AVR's processing might do to music), my room does not allow a perfect 5.1 speaker placement, nor direction, nor is my room perfect, all things the microphoned EXSETT EQ++ setup helps with; so I often find the processed 6/8 channel audio preferrable.

 

[TLS Guy]

I've experimented with HDMI multichannel audio and multichannel analog interconnects (RCA cables). All of my cable were of very high quality both digital and analog, so that cancels that out.

I found 6 channel analog to be noticeably superior in sound quality to HDMI for DVD-Audio playback (my receiver is HDMI 1.1 so SACD can't be compared in this way). At first, I attributed this to "digital and HDMI being good for video but bad for audio."

After doing more research, I think it may be that my Denon 3910's DAC's were kicking my HK AVR 745 DAC's asses.

Question: With my new OPPO-83SE (which seems to have kicked the Denon 3910 to the curb on improved sound quality), of course I'm using the multichannel analog outs because my AVR is "ancient" by manufacturer standards (and HDMI 1.1 ) Getting to my question.... if I set SACD output to DSD instead of PCM, am I bypassing the Oppo's superior DAC's in favor of the inferior one's in my receiver? If I choose PCM, am I getting all I paid for from the 83SE then?

This might all be moot, though, since my HK AVR745 has the ability to bass manage and equalize the multichannel inputs, which I do use it for since it has a good ability to do this well. (I can switch from 6/8 channel and 6/8 channel DIRECT - no AVR bass management and direct pristine pass through). However, as good as 6 or 8 channel direct mode is (bypassing any effect the AVR's processing might do to music), my room does not allow a perfect 5.1 speaker placement, nor direction, nor is my room perfect, all things the microphoned EXSETT EQ++ setup helps with; so I often find the processed 6/8 channel audio preferrable.

First of all DSD is not PCM. So if you convert to PCM any possible inherent advantage of DSD over PCM is lost.

So the only way to hear DSD directly is via the analog outs.

Now if your receiver is offering management via the multichannel analog inputs, then your receiver is converting DSD to PCM. So you would have to use Direct Mode and then you have to come up with a DIY solution for channel balance and bass management. That is the Achilles heel of SACD.

 

[XEagleDriver]

Great Questions

I've experimented with HDMI multichannel audio and multichannel analog interconnects (RCA cables). All of my cable were of very high quality both digital and analog, so that cancels that out.

I found 6 channel analog to be noticeably superior in sound quality to HDMI for DVD-Audio playback (my receiver is HDMI 1.1 so SACD can't be compared in this way). At first, I attributed this to "digital and HDMI being good for video but bad for audio."

After doing more research, I think it may be that my Denon 3910's DAC's were kicking my HK AVR 745 DAC's asses.

Question: With my new OPPO-83SE (which seems to have kicked the Denon 3910 to the curb on improved sound quality), of course I'm using the multichannel analog outs because my AVR is "ancient" by manufacturer standards (and HDMI 1.1 ) Getting to my question....

1) if I set SACD output to DSD instead of PCM, am I bypassing the Oppo's superior DAC's in favor of the inferior one's in my receiver?

2) If I choose PCM, am I getting all I paid for from the 83SE then?

This might all be moot, though, since my HK AVR745 has the ability to bass manage and equalize the multichannel inputs, which I do use it for since it has a good ability to do this well. (I can switch from 6/8 channel and 6/8 channel DIRECT - no AVR bass management and direct pristine pass through). However, as good as 6 or 8 channel direct mode is (bypassing any effect the AVR's processing might do to music), my room does not allow a perfect 5.1 speaker placement, nor direction, nor is my room perfect, . . .

3) The microphoned EXSETT EQ++ setup helps; so I often find the processed 6/8 channel audio preferrable.

Andres,

1) According to the HK 745's manual online, it does not have the ability to accept, nor decode, a DSD input stream.
- On page 3, under INTRODUCTION it stated it has "Two HDMI™ 1.1 and three assignable high-bandwidth analog component inputs for compatibility
with the latest high-definition video sources".
- On page 15, under INSTALLATION AND CONNECTIONS it stated "If the player has SACD capability, you will need to connect the analog outputs of the source to the 8-Channel Direct Inputs".
- I verified this by looking up "DSD over HDMI" in Wiki, and it stated this is only possible with "HDMI version 1.2 or later, standardized in August 2005". Which verified what I remembered as well.

2) No, I do not think so. Because by having the OppoSE output PCM (to be decoded into analog by the 745's DACs) you would be bypassing all the cool circuitry and superior DACs you paid for in the Oppo.

3) I agree with you, the likelihood is the Bass/EQ effects tailored to your room will far outweigh any small advantage of a "pure direct" signal path.

FWIW With my 980H I was not able to discern any difference between PCM vs DSD over HDMI. I have not used the 980's analog outputs since getting a HDMI 1.2 equipped AVR.

The OppoSE via analog into your 745 should be a winner!


Cheers,
XEagleDriver

 

[TLS Guy]

Andres,
FWIW With my 980H I was not able to discern any difference between PCM vs DSD over HDMI. I have not used the 980's analog outputs since getting a HDMI 1.2 equipped AVR.

That is because receivers that do have a DSD decoder convert to PCM right away, as that is the only way any processing can be done.

 

[AcuDefTechGuy]

So the only way to hear DSD directly is via the analog outs.

Actually, you can do DSD-Direct SACD via HDMI as long as both your processor & player are capable.

For example, my Oppo SACD player can output DSD-Direct SACD via HDMI to my Denon 5308. And the LCD on my Denon also reads "DSD-DIRECT".

 

[AcuDefTechGuy]

That is because receivers that do have a DSD decoder convert to PCM right away, as that is the only way any processing can be done.

You mean unless you have the receivers set to DIRECT mode or PURE DIRECT mode, right?

 

[AcuDefTechGuy]

I think the question of whether Digital vs. Analog sounds better depends on each case.

I've also experimented with all this Digtial/Analog/PCM/DSD.

And I think bitstreaming of the original source unaltered (RAW mode/Direct mode on both player & processor) gives me the best sound. But I will not say it's the same with every single person and every single system out there.

 

[andres6]

Two more things

1) I think some people either slightly misunderstood or maybe I misunderstood. You are correct, HDMI 1.1 (which the AVR 745 is), cannot do SACD. However, the multichannel inputs on this receiver can either be in direct mode (no processing), and in (DVD-Audio mode) which means processing is applied. Since I have my Oppo set to pass DSD out of the analog outs, I'm assuming my AVR 745 is capable of processing and converting DSD to music via it's own DAC's (to convert to PCM in order to allow processing), and I'm hearing music come out of the speakers with this method. So unless the Oppo has a handshake correction feature whereby the receiver tells it to change DSD to PCM automatically overriding my settings; this leaves me to try changing the 83SE's setting to output PCM instead of DSD, and see if that improves the sound at all out of the analog outs (The only thing I'm using HDMI for is video only; audio off). In theory, this might bypass one set of conversions by the AVR 745 as it will already be in PCM format so it can apply processing immediately and more directly.

2) If I could set my 5.1 speakers at all perfectly equal distances from my listening position, I think I'd choose the "multichannel direct" over the processed sound. Due to the wife factor and structural space limitations, my speakers are far from equidistant; making the processed sound seem superior in many ways.

 

[XEagleDriver]

Your SACD player is outputting analog not DSD

1) I think some people either slightly misunderstood or maybe I misunderstood. You are correct, HDMI 1.1 (which the AVR 745 is), cannot do SACD. However, the multichannel inputs on this receiver can either be in direct mode (no processing), and in (DVD-Audio mode) which means processing is applied. Since I have my Oppo set to pass DSD out of the analog outs, I'm assuming my AVR 745 is capable of processing and converting DSD to music via it's own DAC's (to convert to PCM in order to allow processing), and I'm hearing music come out of the speakers with this method. So unless the Oppo has a handshake correction feature whereby the receiver tells it to change DSD to PCM automatically overriding my settings; this leaves me to try changing the 83SE's setting to output PCM instead of DSD, and see if that improves the sound at all out of the analog outs (The only thing I'm using HDMI for is video only; audio off). In theory, this might bypass one set of conversions by the AVR 745 as it will already be in PCM format so it can apply processing immediately and more directly.

Andres,

Good discussion.

In regards to 1), I believe you misunderstand the meaning of the Oppo's "DSD" SACD output menu setting--it is in reference to what the HDMI output will do, and NOT in reference to what the analog outputs do--they remain analog, indepedent of this menu setting.

- The reason you are hearing music in your current set-up is because the receiver is getting analog signals from the Oppo's DACs and multi-channel analog outputs and knows exactly what to do with them. It does not imply the receiver is decoding separate DSD channel signals on each of the 6-8 multi-channel analog audio inputs.

As proof, here are a couple quotes from the 83's manual, not the SE manual, but this info should be the same.
(bold added for emphasis)

A) On page 14, under 5.1/7.1 Connections note the manual's use of the term "analog":

"Please use 8 RCA-style audio interconnect cables to connect the . . . analog output terminals of the OPPO Blu-ray Disc player to the corresponding multi-channel analog audio input jacks of your A/V receiver or
amplifier."

Also, I would bet your 745 does not have an illuminated "DSD" light on the front panel while you are playing--another hint as to the analog nature of the signal.


B) Furthermore on page 57, the manual indicates DSD is output ONLY via HDMI, and the Oppo's analog audio outputs use the Oppo's internal DACs to create analog signals:

"3. SACD Output: To select audio output format for SACD.
The options are:
• PCM – . . .

• DSD – SACD DSD data is output over HDMI without any conversion. For the analog audio outputs, DSD data is converted into analog signal directly by the internal DAC. If you use a receiver that supports HDMI v1.2a with DSD over HDMI, or you prefer the sound quality of straight DSD to analog, please select this option."

In summary, with your current receiver your two options for the Oppo are:
- Continue to use Oppo's DACs and multi-channel analog outputs as you are now, or
- Change the Oppo's SACD menu to "PCM", use HDMI for audio, and see if you prefer the 745's DACs instead. (IMHO unlikely to be superior to the Oppos).


Cheers,
XEagleDriver

 

[andres6]

Thanks!!

Eagle Driver, you answered my question perfectly. I was confusing the variables that exist with digital outs (like HDMI) with the constant output of analog which does not vary. Thanks for clearing this up.

I find it highly unlikely my old receiver's DAC's would compete with the brand new Oppo's BEEFED up DAC's being the SE edition.

Here's another question:

1) I remember someone from Oppo telling me when I called them long ago that all outputs on the unit remain on all of the time concurrently (unless you are in Pure Direct mode). Therefore, since the Oppo 83SE has even higher performance DAC's for the 2 channel outputs (yes, even higher than the high performance multichannel outs; which in turn are a cut above the regular 83 non-special edition analog outs), couldn't I use the ultra superior 2 DAC's for my front channels, and still use the other multichannel outs for the rest of the 5.1 or 7.1 system? This would help to eliminate the need for another set of cables, and also configuring my system to switch inputs/functions when I'm listening to 2 channel music instead of multichannel. I find it very convenient to not have to change my receivers settings.