7.1 DAC audio preamp for video

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First of all I do not know if this thread belongs here, so if there's a moderators that thinks it should be moved somewhere else, just do it and let me know.

I have researching this matter for a long time: how to assemble a 5.1 or 7.1 preamp to be used in a high quality home video setup.

It must accept at least one or more HDMI inputs, and offer some way to select them, if there's more than one.

The output should be analog, with RCA sockets, to feed a multichannel amp or amps, and some way to control output level, passive or active.

It may also accept other sources, like stereo channel ones or DSD, with the proper interfaces.

It seems I may have found a company that makes several digital boards, and the most promising board seems to be this one:

ST6000 DAC ES9023x4 HDMI 24Bit / 192kHz 7.1CH for Raspberry Pi - Audiophonics

Apparently you input your HDMI signal, and it extracts and converts it to 7.1 analog audio.

The analog interface has 1/8" sockets, as PC motherboards now have. But I guess you can solder proper RCA sockets to each output.

Perhaps there are other similar systems that I do not know about. But I would like to have opinions, ideas, etc. on this preamp I want to assemble.

I have already asked Audiophonics for more info on this and other of their boards.
 
I have looked for a while. I didn't come across any others that I felt were affordable. I went USB instead of HDMI. Audiophonics is trying to do quite a bit on that board. Seems to fit your criteria. I have no experience with it. Just guessing here, but I would guess that you will only get analog out if you send PCM through the HDMI. Formats other than PCM would just be assed through.
 
The problem I intend to solve is getting to an affordable 5.1 or 7.1 preamp system. I already had two high quality receivers that stopped working after one year (Onkyo) and two years (Denon).

So I don't want to throw my money away with another receiver. As I do not live in the USA, I can't get an Outlaw preamp, which now also became quite expensive. Other multichannel are very expensive, so they are not an option.

The critical problems seem to be the HDMI interface and the Dolby/DTS rights, which seem to bar other affordable HT preamps.

So I thought this might be a way to go, but I haven't yet seen HDMI sockets to go in. The audio on DVD or BD videos is not PCM, so that might be a problem then.
 
Most DVD and BD players will allow you to send a multichannel PCM output. The main issue as I see it that it may be difficult to set bass management and speaker delays with a HDMI source such as a DVD or BD player. From a computer you can do the bass management and speaker settings and send it to this DAC via HDMI. I have looked at the miniDSP nanoAVR-HDA which has analog out, but it sells for $349 on their website. Not sure how much it would be in Brazil.
 
In fact, the sources I will be using more are not DVD or BD players, or at least not to read DVD or BD recordings.

The file type I use more is mkv, sometimes from my HDDs or recorded as data file in DVD discs.

Audio can be AC3 or DTS, which is not PCM. So we better forget about PCM.

The system has to decode DTS and Dolby, and then convert the digital channels to analog, with output at the RCAs or any other type.

From what I read on this nanoAVR-HDA, it doesn't mention what happens to Dolby or DTS decoding.

As I said, I am not familiar with Raspberry, which unfortunately this board is a module of, or if it is at all possible to use it as I would like to. It seems not.
 
No, I don't use a PC to control things, only as one of the sources where I store my files.

A cabled network takes the signal to a TV box, and through it I also feed the portable external DVD player. By the TV I also have the satellite boxes, also with HDMI outputs, the BD and DVD players.

For now I have a small simple HDMI selector, and from it I feed the LED TV or video projector.
 
OK, I'm in contact with an Audiophonics guy, and we are trying to assemble the parts.

Apparently the board can work on its own and does accept HDMI signals. Not sure yet if it does Dolby/DTS decoding.

I also found this other kit that could take care of the analog output level, with a remote:

ALPS IR Remote Control Volume Kit (100K) (6 channels)_Volume Control_Accessories Kit_Analog Metric - DIY Audio Kit Developer

For the input, they suggest using those 5in-1out HDMI boxes, like those sold by Amazon.

Video passthrough is also done, although I don't know what other boards I would need.

But there seems to be a way, apparently.
 
The X6000/ST6000 what you need to know

Dear all,
This is in regards to what you need to know about the X6000 or ST6000 decoder board.

* The X6000 and/or ST6000 are the same. Though designed for the Raspberry Pi ('RPi) because it has the same footprint as the RPi. You don't need the RPi to operate the X6000.

* You need a 5V(dc) 5A power supply and an hdmi input source. The hdmi input source could be a blu-ray player or a media player.

* I have done tests on the X6000 using a blu-ray player. Here are is what you need to do get multichannel sound from the 3.5mm analogue outputs.

* The X6000 does not decode the lossless format of Dolby-HD and DTS-MA. To have multichannel audio at the 3.5mm audio connections, the X6000 will only decode multichannel LPCM.

* Your source player such as the blu-ray player must be able to convert the lossless multichannel such as HD and MA formats (5.1 or 7.1) or lossy 5.1 channels (maximum) to LPCM. The same applies to media players and the Raspberry Pi ('RPi').

* Even though the software settings on the media player or RPi may not explicitly mention LPCM, it is likely that multichannel audio is converted to LPCM.

* Not all source players will convert multichannel lossless and lossy formats to LPCM. For example LG's BP125, BP325, BP240, BP420 and BP450 will convert multichannel audio to 2 channel PCM.

* Check your blu-ray player's manual regarding hdmi audio. Do not set the

player's hdmi output to 'bitstream' or 'dts re-encode' or 'auto'. Otherwise the X6000's audio output sound of noise and buzzing. The X6000 requires that the source hdmi audio signal be LPCM AND NOTHING ELSE.

* If you do set your player's hdmi audio output to bitstream, the X6000's hdmi output will pass that signal on to say your TV or to an amplifier with an HDMI input that can decode the multichannel sound. Similarly, the X6000's optical SPDIF will only output lossy 5.1 audio whether Dolby or DTS.

* Why concern yourself with the 3.5mm analogue audio connections? Simple you may have an amplifier with eight channel inputs and you can put that eight channel amplifier to good use. In my situation I made an eight channel amplifier being a composite of a 5.1 Logitech Z5000 and another two channel amplifier.

* Once you understand what kind of signals handled by the X6000, you will appreciate the awesome sound produced by the X6000's four ES9023 DACS with an SNR of 112dB.

* The X6000 comes under the class of an HDMI repeater/audio extractor. There are many on the market such as the CLUX-11SA and A3080. If you do a search on the X6000's main processor, the EP91A6S, you will find that it is more expensive than the X6000. Even the CLUX-11SA and A3080 are more expensive than the X6000.

* If you shop around, you can get the X6000 for a good price. I purchased mine for AU $64 from dx.com.


Again, once you understand the signals passed through and decoded, you will enjoy the quality of the sound from the X6000.

I have made detailed some notes in reply to a poster at SupTronics X6000-7.1CH Sound Card and much more in depth at X6000K - raspberry pi wiki . For the latter, I made a remark that the data on the EP91A6S processor is vague because the HBR (high bit rate) MA and HD signals are sent to the ILS_x (x = 0 to 3) buses which go to the input of each of the four ES9023 DACs (each DAC for L/R pairs and Centre/LFE pair). But these HBR signals are NOT in LPCM form.

It appears that vendors of the X6000 and/or the XT6000 don't understand the X6000's signal handling.


Nevertheless, you know now and hope you enjoy high quality sound from the X6000,

Regards
Anthony of Sydney
 
You do not need room correction or tone control, in fact I should avoid such correction.

You only need level correction for each channel. That you can do individually for each channel.

Is this for "Cinema" use? I think you'll be in the significant minority if you don't want any signal processing (unless you sit in a a anechoic chamber, equidistant from each identical speaker)

I'm not sure I follow what you are actually trying to achieve.

If you are looking for a replacement for your Onkyo (junk known to fail) and Denon (should really have lasted better), there is a reason they are packed with DSP and that is because you need it to make the effects work properly.

I'm slightly confused by your use case???

FWIW, I use a 2 channel pre/power set up for my hifi. Here I have a valve preamp into a big power amp. When the valve pre is on, the whole cinema set up is totally isolated from the 2 channel system. When the pre amp is powered down, the FL and FR preamp outputs of the Marantz processor are fed to the power amp (passive pass through) as part of my 9.1 set up. The result is totally uncompromised 2 channel sound for hifi and totally configurable cinema audio when required.

Without understanding why you think you need 6 channels of DD or DTS which are not configurable, I cannot see why you would want to go down this route.


There are not enough connections on this to control 6 channels!
 
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Is this for "Cinema" use? I think you'll be in the significant minority if you don't want any signal processing (unless you sit in a a anechoic chamber, equidistant from each identical speaker)

I'm not sure I follow what you are actually trying to achieve.

Sorry, but who told you that room equalization is part of the multi-channel level setup? AFAIK only the levels are adjusted.

I have been an audio engineer for movies for about 40 years, and I think my ears have served me and still serve me well to identify an equalization not belonging in the audio track itself. I do not need an anechoic chamber to tell me that.

What I'm trying to achieve is very simple: eliminate receivers. I still need a 5.1 channels preamp, even if I will not be using the .1 surround, as I believe in having my low bass coming from the L/R channels.

I just need the system to feed in an HDMI signal, separate the channels, decode the Dolby/DTS and feed out the analog outputs, that I will input on quality power amps. No equalization of any kind for me, thank you, only that required by Dolby or DTS to recover the coded audio.

If the preamp has a levelling system inside, that's fine. If not I will use my studio microphones and level meters to adjust the channels levels on each amp, adjusting the gain.

If you are looking for a replacement for your Onkyo (junk known to fail) and Denon (should really have lasted better), there is a reason they are packed with DSP and that is because you need it to make the effects work properly.

Why do you think you need DSP or any equalization to make effects work properly? Where did you read that? DSP is just a tool for certain things, but certainly not essential to 5.1 to work properly. Once again, you are mixing electronic room equalization, which is debatable, with Dolby/DTS processing.

FWIW, I use a 2 channel pre/power set up for my hifi. Here I have a valve preamp into a big power amp. When the valve pre is on, the whole cinema set up is totally isolated from the 2 channel system. When the pre amp is powered down, the FL and FR preamp outputs of the Marantz processor are fed to the power amp (passive pass through) as part of my 9.1 set up. The result is totally uncompromised 2 channel sound for hifi and totally configurable cinema audio when required.

I intend to make it different, using an input selector switch on the L/R amps to get audio from a dedicated Raspberry, probably, connected to my network, with its own DAC.

Without understanding why you think you need 6 channels of DD or DTS which are not configurable, I cannot see why you would want to go down this route.

Who said I do not want them configurable? I just don't want them equalized.

There are not enough connections on this to control 6 channels!

I'm not sure how they are wired inside. They claim to be 6-channel pots.

But there's also these other two:

Panasonic 6-Gang A10K 10K Audio Motorized Potentiometer 25mm D Shaft | eBay

ALPS 6-Gang A100K 100K Audio Motorized Potentiometer 25mm D Shaft | eBay

These seem to have enough pins for each channel separation.

Pity they do not come in other Kohm values.
 
Question about board and case for it :)

Hi, I would like to ask the following. I have a Logitech Z906 5.1 Home theater system(active with integrated amplifier and volume control), Raspberry Pi 4 that I want to use for a KODI media player (OSMC) and play 4K movies on TV using this DAC board + RPi 4 converting audio. The question is with this extension card can I do this without additional controllers and devices and the other thing that bothers me is that there is no separate box for this board but only one in combination with the Raspberry Pi 3, and I cannot use it with a box?
Now the board is on sale in France and I want to order it soon. Thank you in advance :)
 
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