Q: I updated the firmware on my TV and Marantz pre/pro to HDMI 2.0a. But I am using an old Oppo BDP-83 Blu-ray player that is probably not HDMI 2.0, let alone 2.0a. If I get something like the Panasonic UHD Blu-ray player, will I need to change the HDMI cable connecting the player to the pre/pro?

- Mike (MIkeDuke)

A: Probably. The BDP-83 was released in 2009, so it implements HDMI 1.3 or possibly 1.4, both of which support a maximum bitrate of 10.2 Gbps. However, the real question is the maximum bitrate supported by the cable. If the cable is as old as the player, I would guess that it might not be able to convey the maximum bitrate associated with HDMI 2.0a, which is 18 Gbps. This bitrate is important for 4K/UHD, HDR, etc.

Unfortunately, rating HDMI cables for bitrate or "speed" is fraught with potential misunderstanding—in fact, it's not unlike rating the power output from an amplifier or the contrast ratio of a display; it depends on how the testing is performed. Also, some cables are rated for the maximum combined bit rate of the three pairs of wire within the cable that carry the actual signal data—10.2 or 18 Gbps—while others specify the bitrate of each pair of signal wires—3.4 or 6 Gbps, one third of the combined bitrate, which is more common in engineering specs. Then there's the issue of length: The longer the cable, the more potential for signal loss. Ideally, a cable is rated for a maximum bitrate at a certain length.

HDMI Licensing, the organization that oversees the development of the HDMI standard, recently introduced its Premium HDMI Cable Certification Program, which uses independent, authorized testing centers to ensure that cables submitted to the program support the current maximum combined bitrate of 18 Gbps and pass EMI (electromagnetic interference) testing to ensure minimum interference with wireless signals. Cables that pass these tests carry a certification label on their packaging that is designed to resist counterfeiting. Cable companies that participate in the program include Belkin, Blue Jeans, Panasonic, Sony, and many others; for a complete list, click here .


This label assures that the cable has passed the Premium HDMI Cable Certification testing.

Yet another factor is whether or not all the individual wires within the cable are firmly attached to the correct pins in the connectors at both ends. Before HDMI 1.4 was released, pin 14 was not used, and it's not connected to anything in some older cables. But from HDMI 1.4 onward, pin 14 is used for Audio Return Channel (ARC) and HDMI Ethernet Channel. You could use a continuity checker to see if pin 14 is connected, but I'd be shocked if Premium HDMI Cable Certification testing doesn't check the connections of each wire within the cable.

You should also be aware of so-called "powered" or "active" HDMI cables that include a signal booster/processor in the connector attached to an HDMI input. (BTW, this is the only case in which the direction of signal flow through a cable matters at all; a passive cable can be connected in either direction.) Based on RedMere technology, these cables can be longer with thinner conductors than passive cables. However, I recently used RedMere cables that caused sparkly artifacts on the screen, and replacing them with passive cables solved the problem.

Perhaps most importantly, an HDMI cable is simply a conduit for electrical impulses that represent digital bits. As long as individual wires within the cable are firmly attached to the correct pins in the connectors at both ends and the cable can reliably convey 18 Gbps, it should work just fine. You don't need to spend lots of money on "high-end" HDMI cables for improved performance.

If you've got an AV question, please send it to Scott Wilkinson (scott@avsforum.com) or Mark Henninger (imagic, mark@avsforum.com) via PM or email.