DV-983H Setup, USB Audio and Bass Management

Cruising through the Oppo's menu system we didn't find too many surprises. Feel free to reference our review of the OPDV971H which has a very similar menu system. Please note that if you are attempting to use the multi-channel outputs you'll want to properly configure bass management. This includes setting the proper speaker size and also configuring the delay (distance) and level settings.

Under the Video Setup page we found that the Noise Reduction feature didn't do anything visible to affect mosquito or MPEG-2 noise. Oppo claims this setting aids in reducing block noise caused by video compression, however this is far less typical than MPEG-2 noise or mosquito noise. We recommend leaving this 'Off'.

Now, on to actually using the player. It took about 28 seconds to boot and play a title on the Oppo player from Standby. This is pretty sluggish. For comparison, a Denon DVD-1930CI takes around 11 seconds. Of course, we've also seen worse, like the Denon DVD-3930CI which takes nearly 34 seconds. Overall, this isn't of great concern to most users.

One anomaly I discovered with this player was that initially I could not get multi-channel SACD to play through my receiver via HDMI. Even though the DV-983H doesn't output raw DSD audio, the player does allow SACDs to play by outputting PCM audio, meaning that SACDs will play back through HDMI on any receiver with HDMI 1.1 or higher. What I discovered is that HDMI allocates audio bandwidth as a percentage of video bandwidth (it factors in the 24-bit video format timings and maximum sampling frequencies.) Since my player was set to 480p during my audio testing, the system was locked down at 2-channel for SACD. Switching the player to 720p instantly allowed multi-channel SACD audio to be output as expected.

From the Oppo User Manual:

If you use HDMI to connect audio to an HDMI A/V receiver or audio processor, it is recommended that you choose 720p or higher HDMI output resolution when playing high resolution audio content (DVD-Audio and SACD). According to the HDMI specification, the bandwidth available for audio is proportional to the total bandwidth used by video. At 480p/576p resolution, the HDMI specification can only support 2 channels of audio with high sample rate (up to 192kHz), or 8 channels of audio with standard sample rate (up to 48kHz).

Depending on the capability of your A/V receiver or audio processor, if you play high resolution audio content at 480p/576p resolution, you may get reduced audio resolution, incomplete audio channels, or even no audio/video output at all. Choosing a high HDMI output resolution such as 720p or 1080i allows enough bandwidth for all high sample rate audio channels.

Equally odd, was my discovery that the Speaker Setup > Down-mix menu needed to be set to '5.1 CH' or '7.1 CH' in order to hear multi-channel DVD-Audio tracks. When listening to a DVD-Audio disc, I found that I was hearing 2-channel audio with the default setting of 'Stereo'. To me, this menu really should only have to do with analogue audio mixdowns, but Oppo also extends it to the HDMI output for all audio formats that it converts to PCM audio (nearly everything, save DTS and Dolby Digital). Since the AV receiver should be able to handle any required mixdowns or bass management for digital sources via HDMI, we found this to be unusual. This also indicated to me that I wasn't delivering native MLP (PPCM) or DSD to my Denon AVR-5308, but LPCM-converted audio from the DVD-Audio and SACD tracks. I noticed no perceived quality lost in the translation, but it was interesting to note.

Tech Note: Bass Management Galore
Regarding bass management, the Oppo DV-983H provides it, but only in a rudimentary level. The crossover point is fixed at 80Hz and all digital audio formats, save for DTS and Dolby Digital, are converted to LPCM when sent out via HDMI or the analogue audio outputs. This means that the Oppo is potentially ganging its bass management on top of that of your AV receiver. To avoid any unnecessary double bass management, we recommend setting all speakers to Large (regardless of what speakers you are using) in the Oppo's Speaker Setup menu unless you are using the analogue audio outputs.

According to Oppo, the reason they apply down-mix to HDMI output is to ensure users who connect the HDMI output directly to a TV can get properly down-mixed audio. As for applying bass management to multi-channel PCM output over HDMI, the reason is that some older models of HDMI A/V receivers cannot do any processing for multi-channel audio from their HDMI input.

In checking out the USB audio and video functionality the first thing I noted was that the connection was located on the rear of the player. To me, USB connections belong on the front of the device as I'd imagine most people will be using USB thumb drives more than FAT32-formatted removable hard disks. To put the USB port in the back you are guaranteeing that few will use this for any impromptu displaying of images or playing back downloaded music unless you frequently update a portable drive and go through the trouble of connecting it to the rear of your DVD player. It's also not sophisticated enough, as an interface, to cater to larger drives packed with music.

Playback of USB content is easy. You simply hit the button at the top center of the remote and select USB SLOT 1. At that point the USB drive is read (pretty quickly for a 256MB thumb drive). The screen which pops up is pretty much the same screen as is used for SACD content. It shows meta data and allows selection of folders and subfolders to access music. When you play the first track it continues on until the last track in a folder is played. An eye-candy "graphical EQ" displays in the top right and you can adjust the volume output of the player - even digitally via HDMI. The bitrate of the current file is shown at the top and you can fast forward, pause and rewind playback just like with a CD.