SuperUniti - HDMI or optical/coaxial

Personally, I would stick with the way you have it. The results should noticeably be better that way.

What I do is take the optical out from the TV to the SU. So all HDMI's to the TV and one optical cable to the SU.

Sound's good enough for me. Its movies and games not music.

+1 with Alexb - a single optical from tv to SU

Mine is about 15 feet and is fine. Sources on the web quote from 10 to 30 metres as the maximum so 6 feet will be no problem.

That's what we do. Taking the audio direct to the DAC (SuperNait for us) does give lip-sync problems, but going via the TV, then o the DAC works just fine. Presumably, the TV delays the audio stream just enough to match the latency of the picture processing.

I guess it all depends on what your priorities. Your original question asks if it would be 'better' not to take individual digital feeds from your sources to your Naim. In terms of sound quality, it most certainly will NOT be better. However, depending on your ears and your ultimate purpose, it may not sound worse.

Digital stereo audio via HDMI would normally be the last choice for quality, as many compromises are involved. HDMI is a design of convenience for the delivery of a lot of things in addition to audio. Most of these other things compromise the quality of that audio, jitter often being the main problem. I would normally want my signal path as direct as possible. Having said all that, I guess if the jitter is properly reduced by the right DAC(s), or you're not listening critically, or you simply don't hear a difference, then it hardly matters. In such circumstances the most convenient route is the one to take.

You will indeed be relying on the tv to do the conversion. TV's are not known for their high quality analogue output stages, or DACs for that matter .

I'm presuming you don't get the warning about poor lock from any of the direct digital inputs to the Superuniti (it can be a problem from things like cable or sat tv boxes). If you don't, then it's a problem with the signal from the tv, or the cable you are using from the tv to the SU. If you're using optical, check it's seated correctly at both ends or try a different cable (it's happened to me in the past). It could be, though, that the digital signal from the tv is just poor - it does happen.

There's no reason why you can't use all of the possible solutions if you don't mind a little extra cable. That way, you can pick the SU input that gives the best solution for what it is you are watching / listening to / doing at any particular time (eg better for lip sync or better for sound quality).

Hi, if you are getting sync lock warnings, that is very unlikely to do with cables, but would usually indicate the senders transport clock (TV SPDIF circuitry) is not aligned to or accurate enough to one of the recognised spot frequencies that Naim and others use for SPDIF transport. Therefore the Naim receiver is having to establish  the clock from the transport clock using a phase lock loop method. This is inherently a noisier method, but is probably fine for TV.

I use  an optical from my Sky HD box into my NDAC and I have no problems locking - just remember to set the encoding to stereo rather than multichannel. I also use optical to isolate the inherently noisy environments of the TV and STB from my Naim equipment.

BTW, to the earlier comment on HDMI, there is no reason for HDMI  to have more transport jitter than SPDIF, in fact its quite the reverse. SPDIF like HDMI doesn't provide a constant stream of bits but packets of samples within an overall data frame format that are not evenly spaced  but in a regular pattern. The advantage with HDMI is that the transport clock is multiplied up, and so any errors in the senders transport clock will be divided out when the receiver determines the sample rate from the transport clock. Despite this advanced method HDMI is still only specified AFAIK to 192/24/2 (perhaps because there is no demand to go higher) even though technically it could go a lot higher, whereas SPDIF would start to become unreliable.

Simon

If you are having problems with a direct optical connection from tv to SU then I think there is an issue specific to your tv's optical output. My tv (Sony Bravia) takes HDMI from DVD and Freesat boxes and feeds optical to the SU. Absolutely no problems with lip sync and sound quality is excellent. 

Re lip sync - some broadcasts can be pretty dodgy in this area - especially live news reports so it isn't always your system. If you do have a consistent lip sync issue there may well be a way of adjusting it (my Humax Freesat box can do this - buried under the settings menu).

As S-i-S says, HDMI is technically better than SPDIF and the dac in your tv is unlikely to be anywhere near as good as the one in the SU. Of course particular circumstances differ and I infer from your last but one post that direct connections sound better in your system so of course you are right to stick with that but it's not likely to be  the case for most systems.

Theoretical potential for technical superiority does not necessarily translate to superiority in real-world implementation, particularly when bringing a device like a tv into the mix. I can't believe that anyone who wants to listen to high quality stereo music would choose to route it through a tv in order to improve the sound. I'll stick to my 'inferior' connections, thanks. Obviously, for other purposes, it may be necessary or more convenient.