Audio Processor needed: Multi channel to 2.0 (Large Speakers)

[techsamurai]

This may have already been said but the other surround channels are included, which is what "downmix" means... It's a mix. But you do loose the LFE. The LFE requires a separate subwoofer, and decoding.

Hmm, but what happens to 5 channels without a sub? We'd set them in full range and all the bass is then sent to each speaker, right? There's no decoding taking the .1 and splitting it across the speakers, right? The channels have the LFEs baked into the full range, right?

And what happens with .2 and .4 - they are all technically fed the same source (.1) right but can be controlled independently depending on the AVR right?

 

[zakazak]

Dolby Digital, it's from the 1990s.

And yet all of todays movie files are Dolby Digital (Plus) with Dolby Atmos.

This may have already been said but the other surround channels are included, which is what "downmix" means... It's a mix. But you do loose the LFE. The LFE requires a separate subwoofer, and decoding.


Usually, but not always.


Yes. Usually the stereo track is PCM but not always.

DVDs are required to have at least one Dolby AC3 track (it can be stereo or mono) or at least one PCM track (which will be mono or stereo). A DVD player with analog outputs is required to decode both (for compatibility with all DVDs).

I've forgotten the "rules" for Blu-Ray and I don't know anything about broadcast standards/compatibility.

An AVR is compatible with all of the standards so you can play any DVD or watch any broadcast. Except older AVRs without HDMI don't support all of the Bly-Ray formats. The AVR isn't required to support every format (DTS, etc.) but the "shiny discs" are required to have at-least one of the more-standard formats (so everybody with an AVR can play them).

Your TV can decode anything standard too and downmix for the built-in speakers, and any headphone other analog outputs if it has them. It will usually pass-through any digital audio so that's normally decoded by your AVR.

I am not sure if you are correct. The 2.0 track does not include the other surround channels according to wikipedia.
How ever, a compatible decoder can downmix all surround channels into 2.0 (e.g. 3.1 -> 2.0 or 5.1 -> 2.0).
See: https://en.wikipedia.org/wiki/Dolby_Digital#Channel_configurations

Now the interesting thing you just said is: My TV can decode / downmix
Well, according to the specs my TV can decode AC3 / Dolby Digital.. but 99% of todays files are Dolby Digital Plus (not just Dolby Digital).
Not sure if that works as well?
Also: Will it decode it over TOSLINK as well or only via internal speakes, headphone and analog outputs?

All I can say is that if the .1 is a discrete channel then how can the decoder decide which channel to send that frequency to when you don't have a subwoofer?
Does it mean that if you don't have a subwoofer, you don't have bass? That's not the case. Does it send the bass to all the speakers? I hope not

I think they may use the .1 to duplicate bass so the AVR doesn't have to calculate how much bass to send to the sub from the other channels. If there's a sub, all it needs to do is feed it that channel and apply filters. I guess the channels have the full range baked into them and once you have a sub, it's just a matter of sound filters deciding what frequencies to play. No calculation or diversion of LFE necessary.

You're right about downmixing - the center channel gets split to the L and R. I wasn't aware that surround sounds like the rears are played from the front speakers. That sounds funky because a bullet from the back may sound awkward but then again if it's one bullet that only plays from the back speaker and kills an actor coming from the back, not hearing it or hearing just a bit of it would make you wonder how the person died so obviously the sound needs to play on the other channels.

The DD decoder does that so you don't need to worry about that.

That would support the claim of some people saying that 2 channels sound almost like surround. If your speakers have a great soundstage, the sound will envelope you and you wouldn't be missing anything, I guess.

I think it will only "use" the LFE signal if you tell the AVR / Sound Processor that you have a sub-woofer or large speakers with sub-woofer included. At least that is how it worked on my old sound processor (Sony SDP-EP90ES). I think I was also able to set a frequency & dB for LFE. Otherwise the LFE signal won't be used and standard 2.0 / 3.0 / 5.0 applies?

Ye I agree with 2 channel sound being very useable and good as a replacement for surround. That is what I do
But it seems like a DD+ decoder is required for that.
So either my TV can already decode DD+ and output it via TOSLINK?
Or I get any cheap AVR that does the decoding (and maybe also use the AVR as DAC)?

 

[zakazak]

Okay I just checked my LG OLED CX TV Settings:

Audio output: TOSLINK
DTV Audi Setting: Dolby Digital Plus
DIgital Audio Output: PCM
HDMI Input Audio Format: Bitstream (can also be set to PCM)

That sounds to me like I pass the best possible audio input via HDMI (Bitstream).
The TV tries to get the Dolby DIgital Plus audio track (but will fallback to lower tracks if DD+ is not present)
It will then decode it to PCM and output it via TOSLINK.
But is the output 2.0 now or anything else? How does the TV know that it needs to decode / downmix to 2.0 via TOSLINK?

So all I need now is a good DAC and I will have properly downmixed / decoded multi channel content on my 2.0 setup?
Except maybe LFE.. because that doesn't seem to be an option with the LG TV?

 

[techsamurai]

Okay I just checked my LG OLED CX TV Settings:

Audio output: TOSLINK
DTV Audi Setting: Dolby Digital Plus
DIgital Audio Output: PCM
HDMI Input Audio Format: Bitstream (can also be set to PCM)

That sounds to me like I pass the best possible audio input via HDMI (Bitstream).
The TV tries to get the Dolby DIgital Plus audio track (but will fallback to lower tracks if DD+ is not present)
It will then decode it to PCM and output it via TOSLINK.
But is the output 2.0 now or anything else? How does the TV know that it needs to decode / downmix to 2.0 via TOSLINK?

So all I need now is a good DAC and I will have properly downmixed / decoded multi channel content on my 2.0 setup?
Except maybe LFE.. because that doesn't seem to be an option with the LG TV?

I think you're overthinking this and the LFE has confused you. Just forget you know the word LFE until you buy a subwoofer.

Here's an explanation of how bass is handled and how you can mix it.

Selecting "Large" or "Small" for speaker channels setting

support.marantz.com

You need a device that will convert the digital to analog from an optical or eArc to 2 RCA outputs.

DTS is important if you ever want to watch a bluray or dvd. Streaming is mostly DD+ (DD) and DD+ Atmos. DD+ Atmos is irrelevant to a 2 channel system.

 

[twsecrest]

To me trying to get a pair of speakers (2.0) to recreate (fake) 5.1 speaker surround sound is a waste of time.
You might lose some of the sound quality, trying to process a 5.1 speaker signal into a 2.0 speaker setup.
I'm of the option that setting the sources to stereo audio will get the best sound quality IMHO.

 

[zakazak]

So why does DD / DD+ ex

I think you're overthinking this and the LFE has confused you. Just forget you know the word LFE until you buy a subwoofer.

Here's an explanation of how bass is handled and how you can mix it.

Selecting "Large" or "Small" for speaker channels setting

support.marantz.com

You need a device that will convert the digital to analog from an optical or eArc to 2 RCA outputs.

DTS is important if you ever want to watch a bluray or dvd. Streaming is mostly DD+ (DD) and DD+ Atmos. DD+ Atmos is irrelevant to a 2 channel system.

To me trying to get a pair of speakers (2.0) to recreate (fake) 5.1 speaker surround sound is a waste of time.
You might lose some of the sound quality, trying to process a 5.1 speaker signal into a 2.0 speaker setup.
I'm of the option that setting the sources to stereo audio will get the best sound quality IMHO.

But DD and DD+ was made to be decoded / downmixed. Again, check here: https://en.wikipedia.org/wiki/Dolby_Digital#Channel_configurations
It is a feature of DD / DD+. So why shouldn't I want to make use of that?

 

[ZolaIII]

Ufff... Set the TV to PCM only for Toslink (meaning he makes downmix and sends PCM up to 192000 Hz 24 bit to DAC) for plane regular DACs. How good does the TV downmix we probably won't even know but there isn't any employing really good SoC and DSP. It's recommended that you experiment regarding TV downmix options and see how it sounds to you. To me my Panasonic all together with basic EQ and room correction in Cinema Surround Pro preset actually sounds good. Subs with both low/high pass filters over stereo lo level input's/outputs aren't exactly easiest to find but it's menagable.
You can check Sound BlasterX G6 which has (limited regarding both supported formats and to loosy transmission) Dolby support in which case you don't use PCM only but default auto select option. It has deacent DAC (CS43131), does downmix correctly (acording to users) has a deacent DSP which you can't use for much... and it doesn't cost much.
Downsides are for setup and use of additional abilities like EQ you will need a PC (Windows, OSX limited) and drivers are not exactly great, you also need to power it with 2A 5V phone charger (or over PC USB port).
Have a nice time.

 

[zakazak]

Ufff... Set the TV to PCM only for Toslink (meaning he makes downmix and sends PCM up to 192000 Hz 24 bit to DAC) for plane regular DACs. How good does the TV downmix we probably won't even know but there isn't any employing really good SoC and DSP. It's recommended that you experiment regarding TV downmix options and see how it sounds to you. To me my Panasonic all together with basic EQ and room correction in Cinema Surround Pro preset actually sounds good. Subs with both low/high pass filters over stereo lo level input's/outputs aren't exactly easiest to find but it's menagable.
You can check Sound BlasterX G6 which has (limited regarding both supported formats and to loosy transmission) Dolby support in which case you don't use PCM only but default auto select option. It has deacent DAC (CS43131), does downmix correctly (acording to users) has a deacent DSP which you can't use for much... and it doesn't cost much.
Downsides are for setup and use of additional abilities like EQ you will need a PC (Windows, OSX limited) and drivers are not exactly great, you also need to power it with 2A 5V phone charger (or over PC USB port).
Have a nice time.

So:
Audio output: TOSLINK
DTV Audio Setting: MPEG (or DD+?)
DIgital Audio Output: PCM
HDMI Input Audio Format: Bitstream (or PCM?)

That should tell my LG OLED CX TV to properly downmix DD / DD+ content to 2.0?
Should I then use a DAC with room correction e.g. miniDSP or is room correction useless for my speaker setup?

 

[ZolaIII]

So:
Audio output: TOSLINK
DTV Audio Setting: MPEG (or DD+?)
DIgital Audio Output: PCM
HDMI Input Audio Format: Bitstream (or PCM?)

That should tell my LG OLED CX TV to properly downmix DD / DD+ content to 2.0?
Should I then use a DAC with room correction e.g. miniDSP or is room correction useless for my speaker setup?

Room correction as long it's not really, really bad implemented (cheap old AVR's and such) is always a good thing (along of plethora of others starting with acoustic treatment...). I told you to play with options regarding your TV set. It should recognise content by it self you should leave it at Dolby Digital for DTV. Main thing is to set Toslink out to PCM if you want TV to do downmix to stereo from any of Dolby formats it has decoder for and you might fead it with and stream it to DAC as stereo PCM.

 

[ZolaIII]

@zakazak I won't exactly tell you to play with Magnat's placement and believe you did in the past. I believe you could benefit from an amplifier that has higher dumping factor than that old Sony (100) you got that is tolerant to lo impedance loads (as Magnet's are 4 Ohm's rated).

 

[zakazak]

Room correction as long it's not really, really bad implemented (cheap old AVR's and such) is always a good thing (along of plethora of others starting with acoustic treatment...). I told you to play with options regarding your TV set. It should recognise content by it self you should leave it at Dolby Digital for DTV. Main thing is to set Toslink out to PCM if you want TV to do downmix to stereo from any of Dolby formats it has decoder for and you might fead it with and stream it to DAC as stereo PCM.

Thanks, I guess I might go for a miniDSP DAC with Dirac then.
TV --TOSLINK--> DAC --RCA--> AMP

One more question:
The TV support AC4, HE-ACC, DD, DD+ and MPEG as possible DTV Audio options.
If I understand correctly, then AC4 is better than DD+?
So it would better to select AC4 for DTV Audio Option?

 

[ZolaIII]

It's not about what TV supports but what lossy codec will come up in the video stream and that's the Dolby Digital most of the time. Let him do that part automatically (DTV: auto).

 

[Chrispy]

Very weird goals and thread. Why bother?

 

[zakazak]

It's not about what TV supports but what lossy codec will come up in the video stream and that's the Dolby Digital most of the time. Let him do that part automatically (DTV: auto).

Ye, auto is also what I was thinking. That will do the following order AC4 -> DD+ -> DD -> MPEG

Very weird goals and thread. Why bother?

What is weird in this thread?

 

[Chrispy]

Ye, auto is also what I was thinking. That will do the following order AC4 -> DD+ -> DD -> MPEG


What is weird in this thread?

Not using a multich feed properly. Silly to just do 2.0

 

[zakazak]

Not using a multich feed properly. Silly to just do 2.0

Downmixing multi-channel to stereo is using it properly. That is part of what DD/DD+ is for.

2.0 is for sure not silly. I would always take a good 2.0 setup over a cheap/bad 5.1 setup.

 

[Chrispy]

Downmixing multi-channel to stereo is using it properly. That is part of what DD/DD+ is for.

2.0 is for sure not silly. I would always take a good 2.0 setup over a cheap/bad 5.1 setup.

Sorry, can't see any reason these days to stick to 2.0. Silly IMO.

 

[zakazak]

Sorry, can't see any reason these days to stick to 2.0. Silly IMO.

That is fine, no worries

 

[Chrispy]

That is fine, no worries

Yet you ask this in a multich related thread but only want to listen to core 2.0 content or some undefined downmix....neither of which you apparently have any particular idea of

 

[zakazak]

Yet you ask this in a multich related thread but only want to listen to core 2.0 content or some undefined downmix....neither of which you apparently have any particular idea of

It is not an undefined downmix. It is a downmix as intended by Dolby Digital.
It is part of multi-channel codecs and equipment. It has it's use and justification.

You seem to have a different opinion and needs about how you want to setup your audio equipment.
That is fine.. as I said.. no worries But it doesn't help in this thread and is a waste of time for everyone reading this thread.