I've purchased some used AV receivers to use their multi-channel capability. I also modified (butchered) a Denon to get pre-outs to use with active speakers.
Hard to find a used receiver with more than 7 channels. Is there a way to stack HDMI to analog converters to get more than 7 channels?
For example, place a Dayton DSP in front of two 7 channel converters then tell the DSP (Sigma Studio) to distribute the ATMOS channels between the two converters. And I suppose keep adding blocks of channels until you have all 24.1.10 channels or whatever it the number is.
The goal is HDMI in, many analog pre-outs.
Hard to find a used receiver with more than 7 channels. Is there a way to stack HDMI to analog converters to get more than 7 channels?
For example, place a Dayton DSP in front of two 7 channel converters then tell the DSP (Sigma Studio) to distribute the ATMOS channels between the two converters. And I suppose keep adding blocks of channels until you have all 24.1.10 channels or whatever it the number is.
The goal is HDMI in, many analog pre-outs.
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The short answer is no. Are you talking the Dayton DSP-408? It lacks HDMI in so is irrelevant as a controller. Additionally, the HDMI to analog converter can't decide Atmos. Even if you put 2 Atmos AVRs together, you can't get them to knowingly coordinate or only decode part of the signal. Each one will split the entire signal across all the speakers you select on that AVR. Basically unless a lower cost option has come out in the last year or two, you need to spend somewhere between a Corolla and Camry to get true 24.x.10.
As far as I know you can't program the DSP-408 with Sigma Studio. The Dayton unit you can control with SS is the DSPB-K
Dayton Audio DSPB-K DSP Kernel Board
This Analog Devices ADSP-21573 SHARC core can decode ATMOS and you can get a 12 channel evaluation board for ~$550. They also sell a 24 channel evaluation board but you need an HDCP license to buy it so I don't know the price.
Single-Chip Solution for Dolby Atmos AV Receivers | Analog Devices
In those cases, they put everything on one chip. An advantage for a manufacturer but not important for a DIYer.
Dayton Audio DSPB-K DSP Kernel Board
This Analog Devices ADSP-21573 SHARC core can decode ATMOS and you can get a 12 channel evaluation board for ~$550. They also sell a 24 channel evaluation board but you need an HDCP license to buy it so I don't know the price.
Single-Chip Solution for Dolby Atmos AV Receivers | Analog Devices
In those cases, they put everything on one chip. An advantage for a manufacturer but not important for a DIYer.
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I have no idea how multi-channels work but I was thinking that maybe a DSPBK could renumber the LCPM channels. If the 7 channel HDMI converter looks for the first 7 channels and ignores the rest maybe you could send the real 7 channels to one box and then take channels 8-14 and renumber them as 1-7 and send them to the second box. Sigma Studio has logic functions that might be able to renumber the channels.
I haven't checked FreeDSP yet to see if they have HDMI in, HDMI out.
I really have no clue about this stuff and I was wondering if anyone solved for adding blocks of pre-out multi-channels yet.
I haven't checked FreeDSP yet to see if they have HDMI in, HDMI out.
I really have no clue about this stuff and I was wondering if anyone solved for adding blocks of pre-out multi-channels yet.
Well Atmos doesn't come on disk or out of the player as discrete LPCM tracks, it needs to be decoded into those individual tracks. So you will need a device that can decode Atmos on the front end, and as far as pre built devices, you're pretty much stuck with an AVR. Otherwise you will have to use an eval board or DIY a solution, and in those cases you would likely need to contact a sales rep with the chip company to obtain Dolby/DTS licenses.
I'm not certain, but I think my graphics card will decode ATMOS into LCPM. It seems to work with 7.1. For example, my Gigabyte GT 1030 graphics card will deliver LCPM to the 7.1 converter in the photo via HDMI. The 7.1 converter has no decoding capability so I know it's all happening on the GPU.
It would be nice to stack 7.1 converters to get more channels.
Here are the Nvidia surround support formats. Which HDMI audio formats do NVIDIA GPUs support? | NVIDIA
It looks like it's pretty easy to get digital surround decoded on a HTPC. Getting it out to the speakers is the hard part.
It would be nice to stack 7.1 converters to get more channels.
Here are the Nvidia surround support formats. Which HDMI audio formats do NVIDIA GPUs support? | NVIDIA
It looks like it's pretty easy to get digital surround decoded on a HTPC. Getting it out to the speakers is the hard part.
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How will your 1030 send a 35 channel signal over HDMI when according to that page it can only send 8 channels over HDMI?
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Most Blu-ray players will convert Atmos into LPCM signals to send to an AVR, but I am unsure what they do with the height channels.
They come packaged in the TrueHD container within the bed channels (hence the nVidia sending 8 channel Atmos over HDMI). The BDP will simply leave objects and any channels beyond 7.1 mixed into the 7.1 bed channels, even if decoded from TrueHD to LPCM. Unless there's a player with abilities I'm unaware of.
I don't know. But it's a good question so I asked Gigabyte technical support. They might have a good solution since they manufacture the board and know all the details.