I've just set up my old desktop as a Windows 7 media server for a Sony Bravia TV.

With the connection from the PC to TV made out as a video D-sub connector from the Saphire board and a 3.5mm audio connection from the main board audio out, there is no problem with the audio.

But, when I connected an HDMI cable from the DVI out socket on the Saphire board to the TV (Leaving the D-Sub video and 3.5mm audio connections in place) and selected the appropriate input and output selectiions on the TV and PC, video was OK, but there was no audio.

I tried swopping the audio input to the TV by removing the audio jack from the jack socket on the TV that is associated with the D-Sub connector and replacing it in the socket that's associated with the HDMI socket. Still no audio.

Checked the control panel in Windows 7, seems OK, although hi-def audio output is being handled by a RealTek driver by default, whereas the native hi-def driver by AMD (Asus motherboard with AMD chipset) is disabled. The settings on the TV look OK.

Any ideas ?

Cheers.

Nick.

A DVI port does not carry audio, its video only. So if your connecting through a DVI to HDMI cable or through adapters thats why.

HD audio output is nothing to do with HDMI, its just a driver thats driving an onboard audio chipset. its called HD because it can handle bitrates higher than older standards.

I was aware that. HDMI cables don't carry audio.

I found it odd that the existing 3.5mm audio jack conne tion packed up as soon as I installed the HDMI video cable.

Nick

Edited 2 November, 201213 yr by Clunkclick

I was aware that. HDMI cables don't carry audio.

I found it odd that the existing 3.5mm audio jack conne tion packed up as soon as I installed the HDMI video cable.

Nick

HDMI cables do carry audio. Some PCs allow you to output both down the came cable if they have an HDMI port on the PC. It's also possible with a DVI adapter and the digital audio output on your PC (if it has one), to plug both into an HDMI lead.

The 3.5mm jack will only be active when you are selecting the VGA analog input on the TV. It will be expecting the audio to come from the HDMI lead when HDMI input is selected.

When you plug in a bluray etc via HDMI, you don't have a separate audio cable - it's all down the HDMI lead.

There is a separate HDMI port on the back panel of the PC (Asus M488TD-M-Evo main board).

So, I would get the Windows diigital audio output from that ? . . . And if I joined it to the exusting HDMI cable outbound from the PCs DVI socket then the joined HDMI output could be fed into the back of the TV as its HDMI input ?

Nick

If there is an hdmi port on the pc, then just use that to connect to the tv surely?

Your problem will be that if the sapphire is an addon graphics card as opposed to onboard, then the onboard graphics controller will be disabled including the HDMI port. The only way to get that working will be to remove the Sapphire card. Then you'll get audio and video down the HDMI cable, no need for anything else than the HDMI.

Punt the audio to a proper external amplifier

My mistake. I just had a second look at the TV media server PC and realised that it is operating on Integrated graphics (Radeon 4250) - the Sapphire board is in the other machine - my current desktop pc.

So, I should be able to get combined Hi-def video and audio if I replace the current DVI to HDMI connection between the PC and TV with a HDMI only cable (male to male) running between the HDMI sockets on the back of the PC and TV. ?

Nick

In short - yes.

(Right tool for the job etc etc)

In short - yes.

(Right tool for the job etc etc)

Very apt...

Full HDMI cable on order.

As was said above, it seems to have been confirmed that it was the TV was causing the problem. Whilst there were live connections coming from the PC for both HDMI video (From the DVI socket) and analogue audio (From the 3.5mm socket) selecting HDMI video on the TV menu cut-off the analogue audio. Seems odd, in that hi-def video is supposed to be a separate entity to hi-fi audio.

I suppose that's Sony economising on circuitry.

Nick

Could easily be that Sony would expect you to use the right tool for the job. HDMI is a single interconnect to carry both audio and video. If you're using HDMI there's no requirement to expect an analogue audio input. Also using HDMI would ensure that the audio and video are in synch too. Mixing analogue and digital signals can be fraught with synch issues (most easily highlights by having Radio 2 on an analogue radio and a DAB at the same time, makes a lovely echo effect, but stuffs the "pips" time signal)

There is also a very very clear distinction between High Definition and High Fidelity. Just because they both have the word "high" in them, doesn't mean they're even remotely related to each other.

It'll be Sony implimenting the standard correctly.

You can't go swapping between HDMI and non-HDMI inputs. HDMI uses HDCP which requires an end-to-end connection to work.

Make sure you have a GFX card driver which activates HD Audio over the HDMI connection. The latest ones from Nvidia do, they also add Physix & 3D capabilities too, mind you I do have a 2Gb GFX card on board.

All the above points well taken.

All I would say is that there are instances where Digital Video and analogue audio do sync.

I"ve been using the digital DVI output from the same PC to feed a DVI input to an Ilyama lcd screen with analogue audio output from the same rear panel on the PC feeding the analogue input on two Labtec desktop speakers, with no noticeable lag and perfect sync. Que passa ?

Nick

That's fine - it's only HDMI that must be all over the same cable, due to HDCP.

Now I am understanding ?

DVI was a transitional digital video only standard which was formulated before the integrated digital video and audio standard became available and therefiore had to make provision for analogue audio. In cinsequence, there is probably a sync built into PC hardware (Or possibly in software) to ensure that PC analogue output tracked DVI video output.

Whereas the later HDMI standard assumes integrated digital audio with the video and therefore has no need to sync with analogue audio - hence circuitry/software to do this is not provided in the PC or the TV.

Hopefully, the ATI Catalyst MMC software provides the drivers for joint vudeo and audio outout in HDMI si that when the HDMI cable arrives it will be plug-and-play or, at wiorst, plug-reboot-play.

Nick

Edited 4 November, 201213 yr by Clunkclick

Now I am understanding ?

DVI was a transitional digital video only standard which was formulated before the integrated digital video and audio standard became available and therefiore had to make provision for analogue audio. In cinsequence, there is probably a sync built into PC hardware (Or possibly in software) to ensure that PC analogue output tracked DVI video output.

Whereas the later HDMI standard assumes integrated digital audio with the video and therefore has no need to sync with analogue audio - hence circuitry/software to do this is not provided in the PC or the TV.

Bingo! Nothing to do with "Sony economising on circuitry".

DVI was never intended to be used as a domestic/home cinema interface. In a normal office environment (as PCs were used for in those days), there's no requirement for audio, and most monitors didn't have speakers (still don't). Basically you're there to work, not watch movies.

HDMI was designed from the start to be a home cinema interface (hence it doesn't appear as standard on PCs, it's not a *must have" interface, unlike USB). Given the thurst for the general public to enjoy proper "plug and play" it was decided to be one interconnect will do the job. My home cinema setup is only connected by HDMI (Blue-ray-->amp, Virgin Box-->amp, amp-->TV.) No optical or analogue cables. Given the HDCP requirements having anything else enter or leave the digital stream is not acceptable, hence no analogue input, or output, within HDMI.

1 cable, 1 job, 1 standard, lots of happy customers as everything works as easily as plugging it in.

There might be a way to get the DVI working. TV manufacturers know people have PCs and they tend (or tended) to have DVI sockets. Some manufacturers and/or tellys will have a DVI/HDMI combined with RCA audio inputs...