At what point is an external D/A converter warranted or beneficial

gillatgh,

     I think I may have a good solution for you.  But I need to know if you have a full 5.1 home theater surround setup.  That is, do you have a center channel and rear surrounds and, if so, how are they amplified?  Separate amps or a A/V receiver?

Thanks,
  Tim     

gillatgh
:"@noble100,
Yes H/T setup is full blown, front, center, surrounds, sub 5.1 setup. Processor and 5 Ch 250 W amp, D class. (The Krell died)."


Hello gillatgh,

     Okay, a 5 Ch class D amp is excellent for my suggestion.  My suggestion may initially seem a bit extreme to you but it should result in an overall sound that is less harsh and bright.  Here it is:

A.  Remove your Lexicon MC12B from your system. My thinking is the  first check is to determine if the dac in this unit is the source of your brightness issue.  
B.  Substitute your Oppo 103 as your 5.1 surround processor. The Oppo 103 can decode all of the high-resolution audio codecs from Dolby and DTS, as well as uncompressed PCM found on some soundtracks.  This means you can connect most of the Oppo's surround channel outputs directly to your 5 Ch class D amp with the exception of the SW sub and the FR/FL front L/R mains outputs. 
      The Oppo uses the Cirrus Logic CS4382 dac chip to decode and output the lossless audio from its analog 7.1 Ch outputs (you'll just be connecting those for 5.1 and leave both side channels, 'SR' and 'SL', unconnected).  My thinking is that the Cirrus dac chip outputs will likely perform better than the older dac chip(s) used in the Lexicon.

The FR and FL outputs connect to the L/R rca inputs on your Rogue integrated and you use its front panel 'HT' control to choose between the 'HT/OUT' position for cd stereo music playback and the 'HT/IN' position  for ht playback.
The SBR and SBL outputs connect to your 5 Ch amp for the Surround Back L/R speakers, the SW output to your sub and the C output to your 5 Ch amp for the center ch speaker.

For video, connect an HDMI cable from your cable box to the 'HDMI INPUT' on the Oppo.  Connect another HDMI cable from the 'HDMI 2' output on the Oppo to your hdtv HDMI input. HDMI 2 will provide the best picture quality per the Oppo BDP-103 manual.
     This configuration should provide better, less harsh, sound for both cd and ht playback since the digital signals will be decoded by the Oppo's newer internal Cirrus Logic CS4382 dac chip rather then the assumed much older dac chip(s) used in the Lexicon.  
     Please try out this configuration and report back with results.

Thanks,
  Tim

Hi gillatgh,

     Great.  If you have good results, I can explain how to configure the audio on the Oppo's on-screen audio setup menu.for 2 ch stereo playback if you play your music cds through the Oppo.  I can also explain how to integrate your sub for both music and ht playback, too.

Tim

gormdane and gillatgh,

     I have an Oppo 105 and use a similar configuration with my combo 2ch and ht system.  I connect all of the 105's outputs directly to my amps (center, sub and rear surrounds via rca cables and the mains via xlr cables) and the sq and convenience are very good.
     My only reservation is that the 105 was specifically built as a step up in audio quality from the 103 even though they're both identical in video quality.  I know the 105 uses expensive Saber dac chips on all channels and the 103 uses Cirrus Logic dac chips on all channels.  The 105 has no harshness or brightness issues but I'm not as familiar with the 103's sq. and hope it's to gillatgh's liking. 
     Considering Oppo's commitment to high quality, I tend to doubt they'd use the Cirrus Logic dac chips in the 103 if it resulted in bright or harsh audio.  
     Since gillatgh's Rogue Pharoah integrated combines a tubed preamp section containing two long-plate 12AU7 tubes combined with a Hypex OEM class D amp section, I find it unusual that this combination would produce a sound that would be described as anywhere close to bright or harsh.  I've also never read any comments on the 103's sound as having a bright character on either cd or Blu-ray playback.
     Overall, I still expect the system configuration I suggested to provide a well balanced sound but, worst case if some brightness remains, there are some other options left to explore.

Tim

Hello gillatgh,

     Yes, it is a bit strange but it's not brain surgery, right? 
     I no longer believe the Lexicon MC12B is the source of your issue.  It seems, in your current setup, you only use its internal dac chips for ht processing and you use the 103 for cd playback connected directly to the Rogue.

    However, I'd still suggest removing it because it's unnecessary and using the 103 for surround decoding, and connecting its outputs directly to your 5 ch amp, will likely be a significant improvement for ht sound quality and it'll streamline your system to just the necessary gear.
     Once you get the time to reconfigure and setup the 103 as the 5.1 processor, there are some other features on the 103 you can explore. 
     Things like the audio processing setup screens where you set the size ('small' for sub assistance or 'large' for no sub assistance) and relative volume of each of the 5.1 channels, the cutoff frequency for bass sent to your sub and how you want 2ch stereo cds to be processed and outputted.  You could get a head-start on this by reading these sections in your 103 manual. 
     I'll monitor this thread and await updates.

Tim
      
 

Hello gillatgh,

     No problem I enjoy helping the humans.

     I'm glad you like your new setup.  When you have the time, don't forget to go to the Setup Menu and configure your 5.1 system for optimum performance.  

     Go to Setup/Audio Processing/Speaker Configuration.  Use your remote to scroll to the Test Tone box and then use the l/r arrows to select each of the 5 spkrs and the sub.  For each spkr you set the Size (Large for no sub assistance on the spkr Small for sub assistance) Distance (approximate feet the spkr is from your listening seat) Trim (spkr volume-you want all the speaker volumes about the same relative volume at your listening seat).  When completed, you can use the l/r arrows on the remote to sequentially play the test tone through each speaker and verify all channels have the same relative volume when at your listening seat, making small adjustments to Trim and/or Distance on each speaker til the test tone sounds equal from all the spkrs.

     You can also go to the Crossover section and set the frequency at or below which bass frequencies are sent to your sub.

     Probably best just to read the Oppo manual on this stuff, too.

     PM me if you need more help.

Enjoy,
 Tim

Hello firberger,

     Yes, all the Oppos are excellent and absolute bargains.  It's really a shame they decided to exit the Blu-ray market.  All high quality, very versatile gear with excellent support and customer service. 
     With the BDP-203 and 205 being their last units produced, I think all used Oppo models will be in high demand for years to come with corresponding increases in prices.

Tim

Greetings celander,

On my planet, we refer to the humans as "Planet Poopers" but we’re still taught from when we’re newts to treat all the poop for brains species in the universe with respect and civility.

Tim