1. We suffered a brief outage this morning when our host noticed that HTF needed to be moved to a different server due to a hardware failure. That work is now complete. Please post in the feedback area if you have any issues.
    Dismiss Notice

Does the Denon 3802 (and others) oversample source signlas to 24bit/96kHz?

Discussion in 'Archived Threads 2001-2004' started by RyanDinan, Mar 28, 2002.

  1. RyanDinan

    RyanDinan Stunt Coordinator

    Joined:
    Oct 25, 2000
    Messages:
    249
    Likes Received:
    0
    Hello,

    After reading through the recent thread here about upsampling/oversampling, I would like to have something clarified...

    (From the Denon 3802 specs)

    Analog Devices 24 bit, 96 kHz high resolution DACs on all eight channels • Real 24 bit, 96 kHz Digital Interface Receiver

    The Denon 3802 uses 24bit/96kHz DAC's - Does this only mean that it can process such input sources, or does it mean that it also will oversample/upsample input sources such as 16bit/44.1kHz to 24bit/96kHz? If the latter, will it convert both digital and analog input sources to this higher resolution signal?

    I have a HTPC feeding my 3802 with both toslink and coax via the SPDIF output on my sound card. Im wondering if the SPDIF signal just gets output at whatever it originally is (say, 16bit/44.1kHz for CD, or 16bit/48kHz for DVD). If the only way to get a signal oversampled is by using analog inputs to the receiver, I may just have to try that out.....

    How can I be sure that this is occuring? Is there any kHz readout on the Denon 3802? I can't find anything about that in the manual...

    Thanks!

    -Ryan Dinan
     
  2. chung

    chung Stunt Coordinator

    Joined:
    Feb 23, 2002
    Messages:
    234
    Likes Received:
    0
    Ryan:

    The 96KHz/24bit DAC's will work with an input sampling rate of 44.1KHz (CD's), 48KHz (DVD) and 96KHz(DVD) directly. They do not perform sample rate conversion from 44.1KHz or 48KHz to 96 KHz for the digital/optical inputs. If you use analog inputs, then the receiver's ADC's sample them, and I am not sure whether they do 48KHz or 96KHz sampling; I suspect the latter.
     
  3. RyanDinan

    RyanDinan Stunt Coordinator

    Joined:
    Oct 25, 2000
    Messages:
    249
    Likes Received:
    0
    Thanks chung!

    So basically, with a digital connection, Im getting whatever the source is -

    If sending a 16bit/44.1kHz source, would you think that using analog connections, and having the ADC's sample them to (possibly) 24bit/96kHz output would sound better than the digital connections Im using now, which is keeping the signal at the source sampling rate? I guess I really just need to try it out and see, but I was wondering if there may be any technical reasons that would help decide.

    I actually heard from several people that a 44.1kHz source oversampled to 88.2kHz sounded better than oversampling to 96kHz, and that the 44.1 source actually sounded better if left alone, than if it were oversampled to 96kHz....Is this crazy talk?

    Thanks,

    -Ryan Dinan
     
  4. chung

    chung Stunt Coordinator

    Joined:
    Feb 23, 2002
    Messages:
    234
    Likes Received:
    0
    Ryan:

    Now that I have thought about this more, I am not so sure whether 44.1K/16 material gets sample-rate-converted or not. Here are the scenarios:

    (a) You input digital 44.1K/16. Denon recovers data/clock and send them to the DAC. This is the most direct way, but there is no DSP, bass management, tone-control etc. that could be applied.

    (b) You input digital 44.1K/16. Denon recovers data/clock and provides DSP processing, with or without oversampling. The resulting 44.1K/16 output is sent to DAC. This would involve 2 separate digital filtering, one in DSP and the other in the DAC. There is also truncation involved unless the DAC can work with a greater bit depth than 16 at 44.1KHz.

    (c) You input digital 44.1K/16. Denon recovers data/clock and provides DSP. The resulting oversampled data (possibly with increased bit depth) is then sent to DAC. But now the DAC has to work with the higher oversampled rate, and I am not sure if that is possible.

    (d) You input digital 44.1K/16. Denon recovers data/clock and then performs sample-rate-data conversion to 96K/24 and perform DSP. Resulting data is sent to DAC at 96K/24.

    I am not sure how Denon decides what to do, since I do not have that unit. The purist would probably want the ability to do scenario (a).

    It is probably worth mentioning that jitter can be introduced in the clock recovery process. It is debatable whether the effects, in a properly designed receiver, are audible.

    Your CD player may have DAC's that are good enough, in which case you may be better off sending the analog audio signals to the Denon. If you choose direct bypass, those analog signals should not go through any processing. Otherwise the analog signals are sampled at 96KHz/24 and DSP (including bass management) applied.

    Perhaps someone more familiar with the Denon can help you. I am just guessing here. I do not know whether upsampling to 96K/24 and performing DSP would improve the sound or not, but I believe it will be less accurate, since the sample-rate conversion is not perfect.
     
  5. RyanDinan

    RyanDinan Stunt Coordinator

    Joined:
    Oct 25, 2000
    Messages:
    249
    Likes Received:
    0
    Thanks chung,

    Well, Im inputting a 16bit/44.1kHz via digital coax. I DO have tone control and DSP effects - So I guess there is a possibility that it's oversampling to 24bit/96kHz.

    I tried sending an analog signal 16bit/44.1kHz, and it sounded noteably worse than the digital signal - much thinner, less full sound....

    Thanks for the info!

    -Ryan
     
  6. Salvador

    Salvador Second Unit

    Joined:
    Dec 4, 2001
    Messages:
    431
    Likes Received:
    0
     

Share This Page