It turns out that not all HDMI switching receivers pass video unmodified from an HDMI input to their HDMI output. For example, some are clipping levels below black (16) or above white (235), whether the input is limited range YCbCr or full range RGB. This means:-
o You can't use a blacker-than-black test pattern to calibrate your display.
o You can't use full range RGB signals (e.g. from a game console or PC) without crushing blacks and whites.
o If you come across a movie that was authored with black at level 0 instead of 16, you won't be able to recover the missing shadow detail by raising the brightness on your display (for a real example see http://www.avsforum.com/avs-vb/showp...5&postcount=70
The poll is designed to find out if people think this is an important issue. There are two "Yes" answers to establish which is the more common use for levels outside the range of standard video. If both "Yes" answers apply, then choose the one that's more important to you.
The other goal of this thread is to compile a list of which receivers can pass all video levels, and which can't, specifically over their HDMI inputs. This should allow prospective buyers to find out in advance which models pass HDMI signals unmodified.Update: Although more results are definitely welcome, we now have enough reports to see that only Yamaha intentionally limited HDMI inputs to levels 16-235, and only on their initial HDMI 1.3 models. Other major brands have been verified as passing BTB (or if not a fix is promised). Furthermore, a large majority (over two thirds) of people who voted in the poll expressed a preference for passing HDMI signals unmodified. Several popular equipment review sites have also indicated that they will now make this a standard test for receivers.News Flash:
(17-Oct-09) Yamaha finally released new firmware for the RX-Z11 that fixes the clipping problem.News Flash:
(12-Mar-09) Yamaha released new firmware for the RX-V1800 and 3800 that allows them to pass BTB/WTW and full range RGB.News Flash:
(30-Oct-08) Harman Kardon have just released a firmware update that claims to allow the AVR-254 and 354 to pass BTB/WTW.News Flash
(16-Oct-08): Yamaha have just released new models that do not clip (starting with the RX-V1900). They obviously realized their mistake, but are still (so far) refusing to fix the models that do clip.News Flash
(31-Jul-08): Yamaha USA have posted a firmware update for the Z11 on their web site, but it doesn't seem to have fixed the clipping. One report states that BTB is still not visible.
Below I've listed receivers that have been reported as passing, or not passing, signals outside of the range 16-235. Keep in mind that passing BTB with a YCbCr signal likely means it also passes WTW, but it doesn't necessarily mean the same device will pass full range RGB. And some reports might not be as reliable as others (I've tried to filter out ones that don't sound convincing). Also, firmware updates can change things. This list is far from complete, but I have tried to make sure what's reported is accurate.Receivers known to clip HDMI inputs (only levels 16-235 are passed)
Yamaha RX-V1800/V3800 (several reports in this thread http://www.avsforum.com/avs-vb/showthread.php?t=888942
) now FIXED!
Yamaha HTR-6190 (this is the same as the 1800. I own the 6190 and it definitely does not pass BTB) now FIXED!
Yamaha RX-Z11 (reported in this thread http://www.avsforum.com/avs-vb/showthread.php?t=885045
) now FIXED!
Yamaha RX-V663 (confirmed not to pass BTB or full range RGB. see http://www.avsforum.com/avs-vb/showt...2#post13770862
and following posts)
...the 863 is confirmed to clip also (reported in this thread).
Harman Kardon AVR 254 (clipping reported here: http://www.avsforum.com/avs-vb/showt...5#post14067755
...a firmware update has just been released that should fix the clipping (still needs to be confirmed that it works).
Onkyo TX-SR806 (clipping reported here: http://www.hometheaterhifi.com/proce...eceiver_3.html
). However, there are also reports that clipping is avoided if the "Immediate Display" feature is turned off.Receivers known to pass HDMI unmodified (all levels are passed)
Yamaha RX-V1900 (BTB and full range RGB confirmed, see this thread and links from there).
... The RX-V3900 and RX-Z7 also pass HDMI unmodified.
... The new RX-Vx65 series is OK from first reports.
Sony STR-DG820 (BTB/WTW tested here http://www.avsforum.com/avs-vb/showt...0#post14225910
Onkyo TX-SR805 (passes BTB, see http://www.avsforum.com/avs-vb/showt...5#post13442545
...also confirmed for the 605/705, in this thread. So it's likely the 875/905 do too (not confirmed).
...also confirmed for the 606 (see http://www.avsforum.com/avs-vb/showt...2#post15981502
Pioneer VSX-92THX/94THX (passes BTB, see this thread and links from there)
...seems likely the the 90 and 91 do too (not confirmed).
Denon AVR-3808CI (passes BTB, reported in this thread and also in a separate private communication)
...the 2308/2808/4308/5308 probably behave the same (not confirmed).
...the older 887 (HDMI 1.1) passes BTB (confirmed in this thread).
Marantz SR8002 (passes BTB and WTW as reported here: http://www.avsforum.com/avs-vb/showt...1#post13495201
...seems very likely the SR7002 will be the same as the 8002.
...7001 also confirmed passing BTB (in this thread).
Panasonic SA-XR57 (passes BTB as reported in this thread).
Yamaha RX-V661 (passes BTB as reported in this thread).
...the 461 (European version with HDMI inputs) was also reported as passing BTB.
...(it seems the older Yamahas don't have the issue that the HDMI 1.3 models do)How to test
If anyone can contribute new results, please post them in this thread. Note that we are specifically testing HDMI inputs. A simple test with a DVD player is to bring up a calibration pattern that's know to contain blacker-than-black (BTB), and see if it's visible (with your display brightness temporarily turned up above normal). If it is visible with your player connected to the receiver then BTB is being passed. But if it's not visible, don't blame the receiver until you know for sure that BTB is visible with the player connected directly to the display. PC users who rely on full range RGB signals (0-255) will have to try a different test to see if some levels are clipped (since there's no room for BTB when black is at level 0).
Note that some receivers might have a menu option to select full range or limited range, so double check your manual in case you missed this option.
Also note that if your source device has a brightness control (especially likely with HTPCs), you need to be sure you don't use that to raise black above level 16 (otherwise it may appear you can see blacker-than-black when in fact you are still only seeing levels from 16 and up).