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HDMI and two channel audio

Wharfedale Diamond 11.1 & 11.2 Speakers

gobble

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Folks

Can the HDMI port on a common media player be used to output/play FLAC encoded files to a DAC with HDMI inputs? Instead of spdif?

TIA
Regards
 

soundsgreat

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Hi,

Folks

Can the HDMI port on a common media player be used to output/play FLAC encoded files to a DAC with HDMI inputs? Instead of spdif?

Yes it can,it can output normal resolution (44100/6Bit) and also high res (96,192/24) ! but you have to make sure the DAC (which you mention) or the device handles it (the high res offcourse, normal res anything will) !

Regards.
 

gobble

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Thanks. I am considering picking up a tablet up next year which does not have s-pdif, so was wondering how to skip analog out.

How difficult is it to change s-pdif input on DAC to hdmi?

Regards
 

gobble

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Hey
i just realized I can use a USB DAC to output sound. why bother.

Quick question - do usb DACs need a driver for the operating system before they can be used like a plugin soundcard??

TIA
 

hemantwaghe

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Hey
i just realized I can use a USB DAC to output sound. why bother.

Quick question - do usb DACs need a driver for the operating system before they can be used like a plugin soundcard??

TIA

AFAIK no driver.My DAC detected as sound card
May require settings to fine tune!
 

audiodelic

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Hey
i just realized I can use a USB DAC to output sound. why bother.

Quick question - do usb DACs need a driver for the operating system before they can be used like a plugin soundcard??

TIA

USB Dac will work as plug and play with any operating system unix or pc.
 

grubyhalo

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Depends...
Hi,



Yes it can,it can output normal resolution (44100/6Bit) and also high res (96,192/24) ! but you have to make sure the DAC (which you mention) or the device handles it (the high res offcourse, normal res anything will) !

Regards.

Sorry of this is a tad OT, but does anyone know of a HDMI-->SPDIF module that could help feed hi-rez audio to a DAC? Is this even possible?
 

gobble

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Sorry of this is a tad OT, but does anyone know of a HDMI-->SPDIF module that could help feed hi-rez audio to a DAC? Is this even possible?

Its not OT, the end objective is the same :)
Now I'm interested :)

Cheers
 

venkatcr

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Unless you have an electronics in between that converts one signal to another this is not possible. HDMI 1.3 has a bandwidth of 340MHz, whereas S/PDIF tops out at 1.5 MHz.

HDMI can carry data sampled at 192kHz, while S/PDIF generally is around 48kHz, though it can carry more. HDMI goes up to resolution of 48 bits, while S/PDIF tops out at 24 bits.

Thus if you need to convert a HDMI signal to S/PDIF, you need to down convert the signal. This cannot be done by a adapter.

Cheers
 

doors666

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you cant passthru the flac files as your DAC will not encode these. Your PC needs to send PCM out thru the HDMI/spdif for this to work.
 

gobble

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Unless you have an electronics in between that converts one signal to another this is not possible. HDMI 1.3 has a bandwidth of 340MHz, whereas S/PDIF tops out at 1.5 MHz.

HDMI can carry data sampled at 192kHz, while S/PDIF generally is around 48kHz, though it can carry more. HDMI goes up to resolution of 48 bits, while S/PDIF tops out at 24 bits.

Thus if you need to convert a HDMI signal to S/PDIF, you need to down convert the signal. This cannot be done by a adapter.

Cheers

Exactly the kind of info I was looking for. Thanks Venkat.

Cheers

C'ya this weekend :)
 

gobble

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you cant passthru the flac files as your DAC will not encode these. Your PC needs to send PCM out thru the HDMI/spdif for this to work.

That should not be difficult in Linux/Unix world where every device can be treated as a file ... :)

So as long as a DAC has hdmi in instead of s-pdif, looks like it should work.

Thanks.

Regards
 

grubyhalo

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Depends...
Unless you have an electronics in between that converts one signal to another this is not possible. HDMI 1.3 has a bandwidth of 340MHz, whereas S/PDIF tops out at 1.5 MHz.

HDMI can carry data sampled at 192kHz, while S/PDIF generally is around 48kHz, though it can carry more. HDMI goes up to resolution of 48 bits, while S/PDIF tops out at 24 bits.

Thus if you need to convert a HDMI signal to S/PDIF, you need to down convert the signal. This cannot be done by a adapter.

Cheers

Thanks for the info. I'm wondering if there's any DAC module in the DIY realm that understands and handles PCM through HDMI natively...
 

gobble

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Thanks for the info. I'm wondering if there's any DAC module in the DIY realm that understands and handles PCM through HDMI natively...

Right! No need to downgrade the superior hdmi signal to s-pdif signal before working on it.

Regards
 

venkatcr

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Thanks for the info. I'm wondering if there's any DAC module in the DIY realm that understands and handles PCM through HDMI natively...

The bandwidth in HDMI is meant for video and multi channel audio. For carrying stereo data, either Type II AES/EBU coaxial digital cable or a Type II optical with S/PDIF connectors is enough. The AES/EBU standard also supports balanced XLR connectors if your equipment has those. Both these standards support 192 bits or 24 bytes word length which is more than enough for audio signals resolutions. S/PDIF has no limit on the sampling rate used -in other words, there is no specified limit on the quantum of data that can be carried across. It easily carries data sampled at 48kHz, but has been tested to carry upto 192kHz. As of today, you do not have data with higher sampling rates or higher resolutions.

There is not much value in using HDMI standards for these requirements.

Over the next couple of years, AES/EBU standards will be surpassed by USB 3 which has a data transfer rate of 300mbps. In most probability that will become as common and ubiquitous in audio, as USB 2.0 is in computers.

Cheers
 

grubyhalo

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Depends...
The bandwidth in HDMI is meant for video and multi channel audio. For carrying stereo data, either Type II AES/EBU coaxial digital cable or a Type II optical with S/PDIF connectors is enough. The AES/EBU standard also supports balanced XLR connectors if your equipment has those. Both these standards support 192 bits or 24 bytes word length which is more than enough for audio signals resolutions. S/PDIF has no limit on the sampling rate used -in other words, there is no specified limit on the quantum of data that can be carried across. It easily carries data sampled at 48kHz, but has been tested to carry upto 192kHz. As of today, you do not have data with higher sampling rates or higher resolutions.

There is not much value in using HDMI standards for these requirements.

Over the next couple of years, AES/EBU standards will be surpassed by USB 3 which has a data transfer rate of 300mbps. In most probability that will become as common and ubiquitous in audio, as USB 2.0 is in computers.

Cheers

I understand that S/PDIF is all that's needed for audio signals. However, based on my understanding, it appears that the only option to tap a DSD output from a player would be to use the HDMI option. I was hoping to see if a good quality external DAC could be made to handle D/A conversion of DSD signal, instead of letting the player handle it. Now, I know of one way to accomplish this using Denon 19*0/29*0 universal players. This involves tapping the DSD trace before it enters the DAC chip and installing a switch inside the player to toggle between DSD and PCM. Ofcourse if one were to use a DAC like the ESS Sabre, there would be another switch on the DAC's side to change between the 2 modes. I was thinking a HDMI solution would be much more elegant and painless. Ofcourse, it is entirely possible that I could've got it all wrong... :D
 

venkatcr

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Again this depends upon what you are looking for. If you are looking to use the CD layer of an SACD, a S/PDIF is enough. If you are looking to use the 5.1 part of SACD, then no stereo DAC will work, unless you are crazy enough to split the data post HDMI, and use 3 DACS. For multi channel SACD, the only option is a high end surround processor executing the DAC connected to the universal player through HDMI.

Also remember there is no DIY or external DAC that can process the sampling rate of a SACD signal.

Cheers
 
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grubyhalo

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Depends...
Again this depends upon what you are looking for. If you are looking to use the CD part of an SACD, a S/PDIF is enough. If you are looking to use the 5.1 part of SACD, then no stereo DAC will work, unless you are crazy enough to split the data post HDMI, and use 3 DACS. For multi channel SACD, the only option is a high end surround processor executing the DAC connected to the universal player through HDMI.

Cheers

I am interested only in the 2-ch DSD layer of the SACD, not the redbook layer nor the multi-channel DSD layer. Hence, my quest...
 
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