I'm wondering if this might solve the problems with, for example, the 2nd generation AppleTV when being used with HDMI for the main zone, and optical-audio-out to analog line-level-in for a receiver's Zone 2.

[Link: hallresearch.com]

Using what other equipment?

Well, in the example of an AppleTV, you would need:

1. An AppleTV
2. A receiver with Zone 2 and/or 3 that typically will only output sources that are connected to the analog line-level inputs.
3. The Hall Research product that I linked to.
4. An optical digital to coaxial digital converter.


So, unless I'm not understanding your question, that's all you'd need.

 what if you use the optical output of the apple tv into a 2 way optical splitter, then one side of the splitter into the analog converter, and the other side into an optical input on the receiver?   would there still be a delay between the two?  has anyone tried it like that?

That's a good question and I don't know the answer.

I can sort of answer my own question.   I did this with a theater PC and I didn't notice a delay.  It might be safe to assume that the apple tv will act the same.

I've never understood exactly why there is delay in the digital audio unless it is purposefully delayed in the A/V receiver -- and many have adjustments that allow you to delay it even further -- to match up with the video delay, that is, the time it takes in the AVR or in the display for a video signal to be processed into light.

So... if it's that, the optical splitter approach will synchronize audio between the two rooms, but would perhaps cause a greater dissynchrony between audio and video.

Yes? No? Is my original premise wrong?

The only delay I have seen is for lip-synch issues but the sound from Zone 2 has always come out before the Main speakers and I have yet to see a delay for Zone 2/3.

If you're using a Denon, some have the ability to eliminate the delay through firmware update. I was told that using Party Mode can remove this delay but it doesn't work on an AVR-990, which is the unit that's causing my problems at the moment because of the close proximity of the kitchen speakers to the family room (delayed). The reason, as it was explained to me, is that it takes longer for the audio to come through the circuitry when using HDMI input.

Since the analog comes out first, the Hall Research piece would seem to work, since it's able to alter the delay in mS increments.