Yamaha AVENTAGE AV Receiver DTS:X Firmware Listening Test Results

After months of planning and executing a UHD/4k upgrade to my home theater, it was time to implement the final piece of the puzzle: a firmware update to my Yamaha RX-A2050 AV receiver that enables two key elements:

• DTS:X
• HDMI 2.0a (for HDR)

Originally promised in 2015, this firmware update covers Yamaha's CX-A5100 AV preamp processor, as well as the company’s AVENTAGE RX-A3050, RX-A2050 and RX-A1050 AVRs. HDMI 2.0a provides support for High Dynamic Range (HDR) video, specifically the HDR10 standard that is part of  the Ultra High Definition (UHD) specification. I have been using a Yamaha AVR as the heart of a Dolby Atmos enabled home theater for months, and with the recent addition of a UHD player, was eager to add DTS:X and true 4k functionality to my system that includes:

• Samsung UBD-K8500 UHD Blu-Ray
• Yamaha RX-A2050 AVENTAGE AV Receiver
•  LG 65EF9500 4K OLED TV
• Speakers: Polk Monitor 10B (floor)/Monitor 4 (overhead)/CS300 (center)

Figure 1. Advanced Setup Menu

The Update Process

Immediately after reading Yamaha's firmware update instructions, I knew something was different. Typically updates are done from the setup/information/system menu, but Yamaha requires that this update be performed from the advanced setup/firmware update menu (shown above in Figure 1). I believe the reason for this strict procedure has to do with the HDMI 2.0a firmware update that is applied to the HDMI chip set; the advanced setup mode is the only way to ensure that none of the unit's input/output ports are active, which in turn guarantees the HDMI ports are not powered while the new firmware is applied (which ultimately means you only have the front panel display to navigate). Once the update is completed, you can then go into the  setup/information/system menu (Figure 2) to verify the correct firmware version (1.77).

Figure 2. Latest Firmware

Now all that remains is a few configuration changes:

1.      Set 4k Mode to “Mode 1” (advanced mode/4k mode) to ensure compatibility with all 4k modes (50Hz/60Hz/4:4:4/4:2:2/4:2:0).

2.      Set Object Decode Mode to “Enable” (setup/sound/object decode mode).

3.      Adjust DTS Dialog Control if desired (option/dialog) (Figure 4). Note: this parameter adjustment is source material dependent and is typically “locked” (no adjustment). Currently, the only titles I have found that allow this adjustment are on the DTS 2016 Demo Disc (which is not available to the general public).

4.      Set DSP mode to “Straight”.

5.      Pop in a DTS:X source and verify that you are in fact decoding a DTS:X audio (setup/information/audio signal). Figure 5 also yields two important pieces of information about the source (7.1.4) and my system (5.1.2): the AVR is translating 7 base channels and 4 overhead channels into 5 base channels and 2 overhead channels from input to output.

Figure 4. Dialogue Control (left pic) ; Figure 5. Audio Format (middle pic)

Do You Hear What I Hear?

Unlike Denon and Marantz (who are actually owned by the same company), Yamaha has chosen not to implement a “Chinese Wall” between Dolby and DTS up-mixing (the two AVR manufacturers use different DSP engines). That means you can compare Dolby Surround Up-mixing (DSU) and Neural:X on any lossless audio track, which is exactly what I did for the helicopter fight scene near the beginning of Spectre. The significant overhead activity during this scene makes for a good contrast between the two formats. While DSU exhibits a more balanced mix, Neural:X tends to be more aggressive in the overheads. I can see where someone may prefer one or the other depending on source material. For example, a more aggressive mix may be appropriate for heavy action but not for calmer material. That's the nice thing about having a choice, and why I waited a year for AVR models that would support both Dolby Atmos and DTS:X as demonstrated in Figure 7.

Since there are very few native DTS:X discs currently available, I thought I'd take a different approach by sampling Dredd (2013). This was one of the few mixes ever optimized for 11.1 Neo:X and plays well in Neural:X. Dredd speaking to Mama on the PA system (chapter 12) is very, very cool, as is the incendiary explosive he shoots shortly thereafter. The overhead channels make for great atmosphere throughout the rest of the movie. It's hard to believe it took DTS another 3 years to standardize this level of immersion for the home theater. In my opinion, there has yet to be a native DTS:X release this good.

There is a known “bug” that results in center channel distortion when up-mixing a 2-channel source (like music) with Neural:X. First discovered on Denon and Marantz AVR's, this “bug” has been confirmed on Yamaha AVR's, suggesting its origin traces back to the original DTS code provided to AVR manufacturers. Since I don't apply a lot of DSP processing to 2-channel music, it isn't much of an issue for me. However, I fully expect another firmware update for all AVR's supporting DTS:X when DTS corrects the issue in their original source code.

Do You See What I See?

Trust me: there's nothing finer than seeing the “HDR is now on” message displayed on your TV! My first UHD purchase was The Martian, and it doesn't disappoint (OK, I wish it had an immersive soundtrack). Right from the start, you know this is not your typical Blu-Ray. From the opening sunrise in the black of space...to the glistening sand...to the space suit helmet reflections, the contrast is stunning. Without going too far off topic, close attention should be paid to some of the new settings that come along with HDR, like Wide Color Gamut and Deep Color. While the “more pixels”  portion of UHD/4K (UHD signals contain 4 times as many pixels as HD signals) tends to get all the attention, the secret sauce of the UHD standard is increased dynamic range (the difference between the brightest and darkest portions of the screen) and more colors (UHD's Rec.2020 standard can reproduce colors not even present in HD's current Rec.709 standard).

The Long and Winding Road

There are many pathways to UHD nirvana, but as of now one thing is for sure: they all go through HDMI 2.0a / HDCP 2.2. Without this end-to-end signaling functionality, you may not be able to enjoy all the benefits of 4k HDR video and immersive audio. You may get video and no audio, or audio and no video (trust me, I've seen it all). Even worse, you may get “The content will be played in HD because the display or the HDMI input port does not support HDCP 2.2” message! At least for me, the hype of 4k has finally been delivered with the arrival of UHD. Those patient enough to wait for the UHD standard and new HDMI chip sets have been rewarded with 4k and HDR compatibility regardless of other implementations brought to market (Dolby Vision, Philips/Technicolor, etc.). My impression of the DTS:X portion of this firmware update is much the same as it was for Dolby Atmos: native DTS:X material delivers immersive sound as advertised. The Neural:X up-mixer is good, but I still like the Yamaha DSP modes (like Sci-Fi and Adventure) for non-immersive material (both lossless and lossy). One last thing: don't forget to make a backup of your settings (advanced setup/recov&backup) after installing new firmware and/or making major configuration changes. You don't want to lose all that time and hard work!