Only for coaxial (via BCN adapter) input on Chord Qutest. Not works on optical or USB. Test discs....a large bunch (Parasound CDP2000 player used as transport), wich decodes pre-emphasis by itself, and i can compares the sound : Pink Floyd WYWH 35DP-4 2 tracks, DSOTM CP35 no-TO, Thriller Japan for USA 38p11, Friday night in San Francisco 35DP-9, etc.
The Ed Meitner / Museatex IDAT44 and Melior (aka “Bitstream”) DACs feature deemphasis. (DMPH indicators on front panels illuminate when deemphasis is being applied.) Not sure about the BIDAT—anyone know?
Bump -- I am considering buying a portable CD player, but am not sure which portable CD players that I can find new can decode both SUBQ and TOC pre-emphasis. Thank you!
Would that also apply to the DAC within an amp? I have an Audiolab 6000 CDT transport and a Cambridge Audio CXA60 (co-ax cable used). So the amp DAC is doing all the decoding. At the moment I don't know if it does de-emphasise CDs or not and I'm keen to start collecting the CDs releases by Castle Communications in 1986 of Black Sabbath's catalogue.
I can't find a review where the frequency response with/without emphasis is plotted (and given how pre-emphasis has long been dropped from CD production it is not surprising that many do not bother testing this aspect of a player/DAC). However, the DAC chip in your Cambridge is the Wolfson WM8740 which does support de-emphasis via Pin 26: https://statics.cirrus.com/pubs/proDatasheet/WM8740_v4.5.pdf So, provided the amp strips the emphasis flag out of the SPDIF signal, it should be able to properly decode CDs with pre-emphasis. I would suggest contacting Cambridge Audio's technical support to confirm that this is indeed the case. Just because the feature is there does not mean that it has been implemented.
Would that include SUBQ flag location channel as well? None of my amps/receivers have been able to 'see' that one. However I'm not sure if it's even being passed by the player via optical/digital coax Way too many inconstancies on what works/doesn't. A nightmare.
The SPDIF data stream simply supports the presence of pre-emphasis via a single bit flag. A CD player/transport is responsible for extracting the Q-subcode information for all modes (TOC or Track), and should set the flag appropriately. However, as I have written on here before, I do not have a copy of the Red Book to determine what happens in cases where the PRE flag could be different in TOC and Track (it is also unclear how one would set this during disc authoring, but the tools in use back then were very primitive). I would expect Track data to take precedence. I delve a bit into the Q subcode here: Pre-emphasis and OPPO Blu-ray Players
Thanks. I only have one mixed title, all regular, 1 with pre-emphasis- Flag=Table of Contents. Years ago when I bought an Oppo and discovered it wouldn't detect the SUBQ I went on a search for a dedicated older player. I just wanted something I could play any disc in and not have to worry about it
Thanks Black Elk, that's very helpful. I'll get onto the tech department at Cambridge Audio ASAP. Thanks once again for your insight on this.
While I think of it, you may also want to ask Audiolab whether their transport can extract the pre-emphasis flag and insert it into the SPDIF stream. If it does not, it doesn't matter what your Cambridge does!
You can add the following: - Parasound D/AC 1100HD dac - Audiolab 8000 Dac - Rotel Rcd-991 cd player - Naim Cd5x cd player - Rega Saturn cd player - Audio Alchemy dde v3.0 dac This are the ones that I have experienced that do de-emphasis. The Parasound dac have a light to inform about de-emphasis and I must say that rarely I can see it ON... so I deduce that very few CDs needs it. I am right?
@Black Elk I've emailed both Cambridge and Audiolab about whether their systems can work with and decode pre-emphasis. Hopefully I'll get a response and when I do I'll report back.
I was maintaining it a few years ago, I added the location to most of them at the time, from confirmed sources. It needs an update again, quite a few classical, etc.. titles have been added since.
