2-channel vs. multichannel DAC questions

concealer404

My CDP and Blu-Ray player are one and the same, and i ONLY have a 2-channel setup, and i'm perfectly happy watching blu-rays on it.

If i introduce a DAC into the mix for the purpose of improving cd playback, what will happen when the same player gets a blu-ray throw into it?

Would be using Optical out from the Pioneer 51FD to a Maverick D1. Am currently using stereo outputs from the Pioneer.

mmadden28

I would guess though that since you're only concerned with Stereo output that if you have your BR player audio set to Stereo, that everything would probably be fine or the same.

Just a SWAG of course

jinjuku

concealer404 wrote: »

My CDP and Blu-Ray player are one and the same, and i ONLY have a 2-channel setup, and i'm perfectly happy watching blu-rays on it.

If i introduce a DAC into the mix for the purpose of improving cd playback, what will happen when the same player gets a blu-ray throw into it?

Would be using Optical out from the Pioneer 51FD to a Maverick D1. Am currently using stereo outputs from the Pioneer.

You will get the Non-HD track over S/PDIF or TOSLink I believe. You will have to toggle your sound output to HDMI for movies if you want HD Audio.

mmadden28

Are the Stereo tracks (2.1) on a BluRay disc even avail in the HD formats?

jinjuku

From the Hi-Def FAQ:

DTS-HD High Resolution
What it is: Similar to Dolby Digital Plus, DTS-HD High Resolution is an enhancement over standard DTS that offers higher bit rates and better compression. DTS-HD HR is also encoded as an extension to a "core" DTS track. (Note that DTS-HD HR is sometimes referred to as just "DTS-HD", which can be confusing and possibly misleading).
Level of support: Since this codec is also optional on Blu-ray, many players will only extract the 1.5 Mb/s DTS core and ignore the extension.
Examples of discs that use it: 'Basic Instinct', 'Total Recall'.
How to get it:

* Toslink or Coaxial SPDIF - Because SPDIF cannot transmit a full DTS-HD HR signal, the player will extract the DTS core and send the bitstream for that instead.
* HDMI - If the player does not support DTS-HD HR, it will extract the DTS core, replicating the DTS listing above. Some players may decode the DTS-HD HR to PCM and transmit it over any version of HDMI. Other players will instead transmit the DTS-HD HR bitstream to a receiver for decoding (this requires HDMI 1.3).
* Multi-channel analog - Either the Blu-ray player will extract and decode the DTS core, or (on some models) will decode the full DTS-HD HR and convert it to analog.


This doesn't say if the bitstream is encoded 24/192 or not.

concealer404

You guys are kindof talking over my head. I'm not that smart.

I guess my question is... if the source is outputting multichannel signal, what affect (if any) will a DAC with only 2-channel output have?

I'm not using HDMI for audio anywhere. Video only, since i don't have an HT audio setup.

The blu-ray stuff i'm not REAL worried about, other than finding out if the 2-channel DAC will have a negative impact on the sound in that case.

tonyb

If your useing an optical cable to go from BDP to a Dac, I don't see the harm since you only use 2 speakers anyway. Why don't you try an optical to the ref 5 first and see if you like the sound ? The B&K will route all the signals in the digital domain to your 2 speakers plus you get many options in 2 channel listening. The better built analog output stage in the Ref 5 is also a bonus.

concealer404

tonyb wrote: »

If your useing an optical cable to go from BDP to a Dac, I don't see the harm since you only use 2 speakers anyway. Why don't you try an optical to the ref 5 first and see if you like the sound ? The B&K will route all the signals in the digital domain to your 2 speakers plus you get many options in 2 channel listening. The better built analog output stage in the Ref 5 is also a bonus.

Well, my concern is that i believe that my BDP will only output multi-channel format when using the optical output, and that combining that with a 2-channel DAC may cause unwanted affects on the sound.

Unfortunately there's no digital inputs on the B&K, otherwise that would be a good way to test. :frown:

If someone could tell me how/if i can set my BDP to pass stereo signal through SPDIF while playing a blu-ray, then my worries are unwarranted.


{EDIT}

I may have figured it out. The manual is beyond confusing, though. I think i need to set Dolby Digital to go to PCM. (Whatever that means.)

Page 40 and 50 seem to be relevant, if anyone is bored and wants to take the time to double check my conclusion.

http://www.pioneerelectronics.com/StaticFiles/Manuals/Home/BDP-51FD_OperatingInstructions0708.pdf

steveinaz

You'll get uncompressed PCM output from the BluRay--nothing wrong with that, I've been doing it for years.

concealer404

steveinaz wrote: »

You'll get uncompressed PCM output from the BluRay--nothing wrong with that, I've been doing it for years.

Cool, so PCM is an uncompressed digital 2-channel output. I like it. Thanks!

kawizx9r

Iirc, you can change your settings on the BDP when you first turn it on and go to your Home Screen (without a disc in the tray of course).

I saw different options for signal audio out depending what output you were using. When it came to HDMI, the player recognized if the component on the receiving end was 2-channel (stereo) or multi-channel capable (such as a TV). Not sure if the same can be said for optical, but if that's not the case then you can just manually change it.

steveinaz

concealer404 wrote: »

Cool, so PCM is an uncompressed digital 2-channel output. I like it. Thanks!

Yep.
My BRay (coax), CD Transport (coax), and DirecTV box (toslink) are all connected thru my Benchmark DAC1/PRE; then routed to my passive linestage. Remove your analog connectors and go PCM. Make sure to configure your player for PCM.

If you're using HDMI, you'll also still have sound from the TV on those occassions when you don't want the BIG box on.

heiney9

concealer404 wrote: »

You guys are kindof talking over my head. I'm not that smart.

I guess my question is... if the source is outputting multichannel signal, what affect (if any) will a DAC with only 2-channel output have?

If the BD player won't convert to 2 ch PCM then you'll get a hashy popping sound for output. I have no idea how BD players process the sound so I can't say. I had a DVDp (standard player) that wouldn't down convert to PCM which is what is needed for a stand alone 2ch dac.

H9

KrazyMofo24

I'm also running 2.1 though my Dacmagic at the moment with no issues. Optical from the PS3 to the DAC, than RCA to my preamp.

heiney9

steveinaz wrote: »

Yep.
My BRay (coax), CD Transport (coax), and DirecTV box (toslink) are all connected thru my Benchmark DAC1/PRE; then routed to my passive linestage. Remove your analog connectors and go PCM. Make sure to configure your player for PCM.

If you're using HDMI, you'll also still have sound from the TV on those occassions when you don't want the BIG box on.

Steve beat me to it, but make sure you player will down convert to PCM not all do.

heiney9

KrazyMofo24 wrote: »

I'm also running 2.1 though my Dacmagic at the moment with no issues. Optical from the PS3 to the DAC, than RCA to my preamp.

How are you getting the .1 from the dac?

concealer404

heiney9 wrote: »

Steve beat me to it, but make sure you player will down convert to PCM not all do.

Yeah, it does, i just have to figure out how to navigate through my eleventy billion screens. Can't i just push a button and make it happen or something?

steveinaz

No, it's in your audio setup. In digital out, select "PCM" (or "LPCM" same thing) instead of "bitstream."

concealer404

steveinaz wrote: »

No, it's in your audio setup. In digital out, select "PCM" (or "LPCM" same thing) instead of "bitstream."

Heh, i was joking Steve. I'm sure i can figure it out, i just have a deep hatred of stackable menus.

heiney9

Just be aware even if it has a PCM setting, in some instances it doesn't work. That's not the norm but it does happen and it seems the newer the machine the more likely. I had an Adcom GDV-850 dvdp and I never could get any sound other than hashy glitching when used the external dac and the pcm setting on the dvdp. I sent it back.

H9

KrazyMofo24

heiney9 wrote: »

How are you getting the .1 from the dac?

Well I'm not sure exactly how it works. I have the sub and the speakers connected to my preamp. I have my mains crossed over at 80hz.

So I think the preamp sends the mains any frequency above 80hz and either the full frequency or just the lows to the sub.

On my PS3 settings I only have PCM checked mark as supported audio types.

heiney9

I wasn't aware of an outboard dac that did more than a stereo signal. I bet it's not a true 2.1, as I'm not sure how the LFE would be output to the sub since the dac can't pass any LFE signal material. Using the dac would override any processor setting in your pre since it's communicating with the dac with PCM only.

I was just curious when you said 2.1 as I've never known of an external dac than can output more than 2 channels. I'm sure it sounds good but it's probably not true 2.1 processing. I wanted to clarify that in case someone thought they could get true 2.1 processing with an external dac.

H9

P.s. Or my assumptions are incorrect, so anyone please feel free to elaborate. Perhaps the LFE is processed separately at the pre-amp level and isn;t part of the stereo signal fed from the dac.

P.s.s. I assume your pre is also an HT processor?

KrazyMofo24

heiney9 wrote: »

I wasn't aware of an outboard dac that did more than a stereo signal. I bet it's not a true 2.1, as I'm not sure how the LFE would be output to the sub since the dac can't pass any LFE signal material. Using the dac would override any processor setting in your pre since it's communicating with the dac with PCM only.

I was just curious when you said 2.1 as I've never known of an external dac than can output more than 2 channels. I'm sure it sounds good but it's probably not true 2.1 processing. I wanted to clarify that in case someone thought they could get true 2.1 processing with an external dac.

H9

P.s. Or my assumptions are incorrect, so anyone please feel free to elaborate. Perhaps the LFE is processed separately at the pre-amp level and isn;t part of the stereo signal fed from the dac.

P.s.s. I assume your pre is also an HT processor?

After reading the manual again from my Parasound. It looks like I have it connected wrong. I should have it connected to Line/Audio Input which the input for connecting a CD player or DAC. Instead I have it connected to the Tape audio out and have it to set to Preamp direct. Which bypasses any surround sound processing and routes it directly to the preamp circuitry.

I don't know maybe it's being processed again by the Parasound and that's why I'm able to use the sub. I'll try to do some more research on it, and I'll try moving the dac to the Line/Audio Input.

steveinaz

heiney9 wrote: »

Just be aware even if it has a PCM setting, in some instances it doesn't work. That's not the norm but it does happen and it seems the newer the machine the more likely. I had an Adcom GDV-850 dvdp and I never could get any sound other than hashy glitching when used the external dac and the pcm setting on the dvdp. I sent it back.

H9

That's odd, I've been doing it for years (DVD and BluRay), PCM has always worked for me.

heiney9

steveinaz wrote: »

That's odd, I've been doing it for years (DVD and BluRay), PCM has always worked for me.

Perhaps the Adcom dvdp I had was a fluke and all pass PCM properly, but in my case I tried in vain and even though I choose PCM on the screen all I got was a hashy clicking sound.

Just making the OP aware this could possibly be an issue.

H9

steveinaz

Some players will have an issue if "secondary audio" is enabled, but I think a firmware upgrade has fixed this issue.