</SPAN>After countess hours of fiddling, I have found what I feel produces the finest 2 channel sound I have ever achieved. The results are increased clarity, increased bass response, better impact, and reduced sibilance.
I have tried numerous drivers and settings for the BDP-105 USB DAC and Marantz AV8801.
The BDP-105 USB DAC has made it clear to me that handling of the bitstream can have profound effect on the sound quality. Bits are bits, but they have to delivered at the right time.
Disclaimer:
Of course, since it is just me, all my comparisons and observations are sighted.
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All judgments are made with quick-switching.
I have absolutely no bias since I could care less which settings are preferred.
No warrantees or suitability for any purpose is implicitly or explicitly implied.
AV8801 Settings</SPAN>
For some inexplicable reason the Video settings effect the sound of the processor and most noticeably using the 7.1 analog inputs.</SPAN>
Here is my AVS post on how to quick-switch the AV8801 using the web control interface:
http://www.avsforum.com/t/1431914/marantz-av8801-preamp-processor-official-owners-thread/9330#post_24007588
Note: if you are changing these settings you with the menus, changes do NOT take effect until you exit one level. The sound must mute or the change has not taken effect.</SPAN>
My Settings are:
Lip Sync:
Off,
HDMI control:
Off
Video Mode:
Game (this setting actually reduces the power usage by about 1 watt)
Video Conversion:
Off
With quick switching I can clearly hear the differences. Without that, I am would not have been able to isolate the differences incurred.
Windows J River Settings</SPAN>
The BDP-105 USB asynchronous DAC bypasses all processing within the player.
I tried a number of drivers that all bypass the windows mixer: Kernel Streaming, ASIO, and WASAPI (which defaults to event driven with the USB DAC clocking the data). J River Equalization and other processing are turned off.
It is amazing how these drivers and options can alter the sound given that this should all be the same digital stream decoded by the BDP-105. This is not something I expected.
ASIO is always 32 bits, but with Kernel Streaming the 24 bit USB driver can receive data padded to 32 bits. This does have an audible effect and I prefer the 32 bit packing so I assume the driver did as well.
Kernel streaming is a less dynamic than ASIO or WASAPI. WASAPI was the most revealing and dynamic without being harsh.
In the end, I settled these J River Settings (Options Menu): </SPAN>
Audio Device:
Oppo USB AUDIO 2.0 (WASAPI)
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Device Settings (Default values):</SPAN>
Open device for exclusive access (checked)</SPAN>
Maximize Device Volume during playback (checked)</SPAN>
BitDepth: Automatic
Buffering: 100millisconds</SPAN>
USB Audio Cass Driver Control Panel Settings</SPAN>
The last setting to be tuned was the driver supplied by Oppo found in the tray with a Red
T icon. I played with the ASIO buffer size but found no discernible effect. Except, if you set it too low, you get an error or playback is a disaster. So I set it to the maximum 8192 samples.
The USB Streaming Mode also has an impact.
I found that minimum has the best dynamics and clarity and is substantially different from the other options. You would think that more is better, but it appears to not be the case here.
USB Audio Driver Settings:
USB Streaming Mode:
Minimum latency</SPAN>
ASIO Buffer size:
8192 samples</SPAN>
If you have either of these devices and like to try things, see what you think.
- Rich
