How can I output direct sound unchanged by Windows

I have an Onkyo TX-NR646 Amplifier connected to my PC via the DVI port on my Video Card. My video card is a Nvidia GeForce GTX 1050 Ti. Its a great amp and I want to use it's hardware encoding rather that Windows getting involved. For example, if I am watching a TV show with a 5.1 soundtrack, I want the amp to receive that signal unchanged so it can process it. If I am watching a movie with a Dolby Atmos, I want Windows to output the sound and pass it directly to the amplifier. Basically, I don't want Windows doing anything with the sound other than passing it on to the amplifier. No managing it for the number speakers, no adding of spacial effects etc

This would have a couple of benefits ;

1) I don't need to manually change my speaker configuration based on the sound track for the movie / music
2) My amplifier would recognise the sound type and display it on the front of the amp (ie. 'DTS-HD Master Audio')
This is my default device ;



When you click 'Configure' it shows you ;



Ideally, there would be an option here that says "Output sound in original format". Currently I am forced to chose one of the options, it then breaks down the sound according to my setup and passes it to the amp. Which is annoying, as I want to the amp to handle the sound, not my PC.

If anybody has some ideas about how to setup this up, I would be very grateful

What does the receiver show as the audio format when you are playing Atmos content on your PC? What software are you using to play it?

My understanding is that Dolby passthrough/bitstreaming is controlled by the player application.

Thank you PolarNettles - I worked this out last night, you are right - my understanding of the technology was incorrect. I assumed all output would go via the Windows High Def Audio and it was that which was causing the conversions, however this is incorrect. As you rightly mentioned, the application is dictates whether the data is raw/unchanged (bitstream) or whether it's converted and then send onto the Windows High Def Audio device.

For anybody reading this article trying to do something similar, I am using MPC-HC (an excellent & free video player for those who don't know it). I followed the excellent article here which shows how to setup MPC-HC to only output audio as bitstream. This now allows my amp to receive the original format audio. Now if I play a Dolby Atmos or a 7.1 sound file via MPC-HC, then the amp recognises it's format and plays it accordingly.

Thanks PolarNettles for taking the time to reply and helping me and other people who will find this thread and find this info useful.

Hi there
@PolarNettles and @ukpaulo.

Reasonable advice -- BUT :

Even better if you have optical output as the DAC's (Digital --> Analog converters) are usually a lot more crappy on a computer than a high end amplifier. However unless you can cable that directly into your amplifier (optical cables are quite short for domestic stuff) you won't be able to adopt that solution. (The remote amplifier will also need to have an optical IN.)

Once you've passed any signal through the computer DAC you've lost fidelity and often quite a lot of it -- Games playing / movie designed sound output are usually designed for crappy computer speakers rather than serious Hi fidelity stuff -- sorry to disappoint you but that's the way it is.

The only way IMO with minimum fidelity loss is to have the audio file shared with a remote receiver such as a decent high quality Internet connected / LAN connected device that has a high quality DAC in it and play the file using the remote device's hardware. Even a humble Amazon fire TV box will have audio that blows away any computer hardware -- plug the output of the Amazon box into the Onyx amplifier DAC on the Amazon fire TV box is quite good and use something like KODI to play the file from the amazon TV box into your target amplifier.

For really high quality stuff - don't bother with Blu Tooth --fine for a huge amount of stuff but terrible for really high quality stuff. Internet transmission can give absolute high quality.

Cheers
jimbo

The OP is talking about bitstreaming the Dolby audio track to their amp over HDMI. By definition that is bypassing the PC's DAC.

PolarNettles said:

The OP is talking about bitstreaming the Dolby audio track to their amp over HDMI. By definition that is bypassing the PC's DAC.

Hi there

sorry @PolarNettles
but you are wrong there --HDMI converts Audio !!! which is what you don't want. Also Dolby is a form of encoding so some manipulation of source takes place..

Best thing is for the original computer to just SEND the file and the remote app does all the work. !!!! Why let a computer even touch the file apart from sending it (basic simple networking will do it 100% losslessly. Remember even Dolby coding involves some manipulation of the input source -- I'd trust the remote device far more than any consumer grade computer. !!!!

Just send the source file bit for bit to target device -- most computer Dolby systems are JUNK anyway for high fidelity music -- they are fine for Games, films with mega sound effects etc - but for decent music -- FORGET,

(I like high quality Music -- I nearly scream any time I get on a train in UK and hear those people with the awful bud headphones where I I think the unfortunate passengers hear more than the wearer of those instruments of Torture !!

I use studio grade speakers - I won't say at what cost -- and have a lot of high end Studio gear as I cut bespoke Vinyls for people as a profitable sideline to my day job as I'm coming towards retirement ).

Cheers
jimbo

Yes, Dolby is a form of encoding. So is 16-bit PCM from a CD. We are talking about pre-encoded Dolby audio from a video here so there is no better audio source.

With bitstreaming there is no decoding of the audio on the PC side - the exact encoded data from the video is streamed over HDMI to the receiver to do the decoding. How is that any different than sending an audio file to the receiver?

There may be reframing of the audio data to get it into the HDMI packet format. But, again, that is no different than the packetization from sending a file over Ethernet+TCP+SMB to the receiver.