RMAF 2012 – Seminar: HDMI Digital Connectivity

When Nordost Cables asked Jeff Boccaccio of DPL Labs to speak about HDMI Digital Connectivity at RMAF 2012, he remembers thinking, “I’m not sure if these audio aficionados are prepared for this!”  HDMI is really a game-changer in audio.  By using real life examples and simplifying terms, Brocaccio taught me some tips and tricks to improve both my home audio and cinema set-ups.

He began by showing us a still from Goldeneye as we’d watch it in Blu-Ray now. Definitely a nice, clear picture.  Slowly, he degraded the signal to the point where it was almost fuzzy and explained that this is how we watched movies on our VCRs – “and we were happy with it!”  Watch a few snippets of the lecture below:

What is interesting, is we can take the same principals in AV and apply it to Audio.  Bandwidth is primarily the biggest challenge, but we also have to examine the source component’s integrity.  In this case, the quality of any digital signal is determined by its reliability.  For example, many of us have encountered visual “tiling” – bits of missing digital information the cause blank squares in the picture.  This can also happen with HD Audio.  It’s our job to figure out if the cable is too long, if the cable is a poor match for the component (sometimes 2 wrongs do make a right!), or if the component is not timed properly.

Furthermore, the last three attributes that make up the HDMI Collective are Intelligence (that’s the Digital Display Control or screen+audio resolution), Supply Voltage, and the Hot Plug Trigger.  The Trigger basically controls the digital information exchange between the source component and source itself.  When this piece isn’t dialed in correctly, we end up with gaps that make a very poor viewing or listening experience.

For me, the biggest takeaway is that HDMI cables should never be any longer than seven feet.  We lose chunks of information in every extra foot of cable – and with the way that HDMI signal processing works now, we can afford to lose information without causing instability at short ranges.  The industry, however, is fighting to catch up with the technology and in the near future, we won’t be able to afford losing the same amount of data with noticing a decrease in quality. If you’re having trouble with your current home set-up, Boccaccio strongly suggests using a shorter cable before buying new components or calling electricians.  A shorter cable could save you a boatload or time and money!

– Anna V.

Jeff Boccaccio has co-authored a book entitled, “HDMI Uncensored.”  Check it out here!


  1. 7 feet HDMI cable runs?
    Use shortest cables available?
    C’mon man! where have I heard that before?

    Practicallity plays a huge part in every home entertainment affair anyone assembles… unless of course it’s being comprrised by someone without any moneytary restraints.

    For that matter then, What are those with ceiling mounted projectors to do?

    Afix their entire systems across the roof and drill a hole for a secure cable run to it?

    1.5M and or about 6 ft with digital audio wires, and now the same thing with HDMI, almost? Sounds mighty familiar and a tad funny to me… unless we recall the compromises every or nearly every, HT outfit endures.

    without throwing in the budgetary card here, I’d submit, as usual the factor of compromise, and the influence of those eyes subjectively viewing the display, and those ears which are hearing the audio aren’t perfect either, so the degree to which the length of a HDMI cable degrades the rendition is rather a moot point in an immense number of instances.

    I’ve a HDMI run of around 26 feet between my processor or at times past, my receiver to the front projector and any number of people who have seen that 115 inch 720P displayed image have exclaimed no disappointments following or during the event.

    one has to arrange that which they can determine as their best possible solution regardless the effort, in the end.

    Past the rumors and fantasies of claimed perfection lay the constraints of actuality and it’s within those boundaries of reality we are often forced to abide.

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