JohnAV, bp, jd, etc., apologies in advance for this but I'm confused and would like some schoolin' in digital processing, DSD and AL24 processing plus. This comes up in the context of comparing processing in the Denon vs the Oppo BRP-83. I would like to have a more in-depth understanding of my results. I posted this in the 83 thread:
"I A/B'd some SACD's and with Oppo set to output DSD (AL24 light OFF) it sounds distinctly better to me than does PCM (AL24 light ON). To my ears this is mostly a matter of additional detail and clarity although both sound very good. With the BR hidef codecs it is not so clear for me. I listened to several of the soundtrack music selections and effects in "Watchmen", again A/Bing bs vs PCM. I seem to be hearing the PCM as slightly louder overall. Without taking any measurements, if I equalize for that by cranking the bs by 1.5 dB, they sound pretty damn close, to my ears."
The 2809 and 3808 spec sheets indicate "AL24+ FR/FL", but both owner manuals have the following descriptions:
"AL24 Processing Plus for All Channels
DENON has further developed its proprietary AL24 Processing, an analog waveform reproduction technology, to support the 192-kHz sampling frequency. AL24 Processing Plus, thoroughly suppresses quantization noise associated with D/A conversion of LPCM signals to reproduce the low-level signals with optimum clarity that will bring out all the delicate nuances of the music. Equipped foe not only front left and right channels but also for the surround left and right, center and subwoofer channels."Equipped for not only front left and right channels but also for the surround left and right, center and subwoofer channels."
So I'm thinking the 2809 only uses this AL24 processing only on PCM input yet apparently when it does its own DAC on the "pure" bitstreamed signals such processing is not needed. Yet it has often been stated that "bitstreaming HiDef codecs or having your player decode them and send PCM to your AVR should sound the same"-and that's pretty much what I heard. Hmmm...so what is the role of the proprietary AL24 processing if this is the case for AVR's in general?
Interestingly, in response to my post, jcrys posted in the 83 thread
http://www.avsforum.com/avs-vb/showt...8#post16904058 that he had the
same impression, DSD sounds better, but not either way of decoding the HD BR codecs. And his unit has “Advanced AL24 Processing” which is applied to all channels and sound modes (except DSD Direct) all the time.
I would appreciate any enlightening pedantic explanation. TIA.