Surprisingly enough, I couldn’t find an answer to this anywhere:
Do dCS DACs/Players properly EQ a CD encoded with pre-emphasis?
I guess that is a pretty niche question these days as CDs with pre-emphasis have not been made since the very earliest days . I will guess maybe 1985 ? Further most record labels never adopted this possibility. There were a few cock-ups with it by those that did e.g using pre-emphasis but neglecting to set the code in TOC or subcodes.
I think a response from one of the dCS engineers is needed. I have a vague memory of a piece somewhere explaining that there was a method but the elapse of time since raises further questions.
The existence of pre-emphasis in CDs is normally notified by a flag ( code) in the metadata i.e. in TOC. However as this was a short lived activity although perhaps the Sony CD mechanism in early dCS transports/players did recognise it, the question is do their subsequent Esoteric and D&M based transports/players ( I’m not sure what is used in Rossini Player) still have the facility?
Another question is whether or not the code is recognised and passed on by ripping software and, if so, what is the result?
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Very few rippers apply the necessary EQ, which is how most people discover they have a disc with pre-emphasis; it sounds bad when ripped but OK when played in an old school CD player.
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Thanks Bill.
It isn’t the ripper which can apply EQ. It is whether or not the lag is recognised and passed onwards. The actual EQ is applied at the DAC output stage.
Thanks for the list. As you can see most CDs having pre-emphasis were made for the Japanese or US markets but there are more than I expected and some big sellers are there. Being in the UK such discs are rare here - I only have one.
I collected Brazilian CDs from the mid to late '90s and I remember reading - I don’t know where - that many early CD transfers of that music had pre-emphasis. I still have the discs. I agree it would be good to know whether dCS DACs correctly handles this.
I have hdcd discs too, a much later thing. I didn’t believe they’d really catch on… and they didn’t.
The most common method is to apply digital EQ via an app like SoX after ripping, as once divorced of the disc TOC/CD subcode data, there’s no way to tell a DAC to apply the de-emphasis EQ curve. Supposedly iTunes/Apple Music notice the pre-emphasis flag in the TOC/subcode data and digitally apply a de-emphasis EQ to the track when ripping.
(There’s no way to directly tell a DAC that a FLAC, ALAC or any other digital file requires de-emphasis, which is why software techniques must be used when ripping or manually thereafter.)
Here’s a good discussion of the issue:
My main question is whether the right thing will be done if I put a CD with pre-emphasis into my Rossini Player APEX (or if someone has a Vivaldi One APEX) and/or if dCS transports can somehow signal dCS DACs to apply a de-emphasis EQ curve.
If there’s no capability within dCS DACs to apply a de-emphasis EQ curve, that answers that question pretty neatly - that it must always be done while ripping or manually after, but cannot be done playing an actual CD.
The dCS Purcell/Delius and 974/955 series supported de-emphasis. So, dCS definitely had the code for it.
I’m guessing the current dCS transports passthrough the flags transparently, but since the current range of Upsampler/DACs have no specific de-emphasis configurations (50/15us, CCITT J.17, or Auto), presumably they don’t support de-emphasis? 
The original 2014 review of Vivaldi in Stereophile states that the transport “recognises the pre-emphasis flag” but doesn’t say anything more. Regarding ripping: I think dBpoweramp, to mention one such piece of software, will apply de-emphasis during the ripping process.
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Thanks Simon. I think I stand corrected. This thread from the dboweramp forum may help.
However in regard to de-emphasis being applied directly on the replay of CDs with current dCS transports/DACS, if Anup is correct ( and he usually is), the answer is no.
As above, my vintage Purcell/Delius has several options on how to treat CDs with deemphasis - I’ve left it at default setting.
The default setting is “Auto” and it depends upon the transport recognising the pre-emphasis flag and it passing this in the data stream to the dCS processor for the de-emphasis characteristic to be applied. Of course the dCS transport of this era ( Verdi La Scala) did this. Players of that time commonly would recognise the flag but I have no idea if, being players, this was used internally only. Nor do I recall seeing any yransports/ players of later times specifically citing this feature. That is not to say that they don’t do it but that they remain silent on the topic.
So, how do you manage? Obviously without the flag being recognised and the data stream amended in some way, the dCS " Auto" de-emphasis will not do anything even if selected.
Is there some kind of notification showing when de-emphasis is activated?
Not sure, never had a player that showed when deemphasis was active, but many of the CD players I’ve tinkered with have the circuitry. I think the flag would be detected at the DAC once the data is decoded, not the transport…but I really don’t know for sure 
Hi Guys,
Although it predates me I am informed that the Elgar / Delius generation DACs supported CD pre-emphasis but since then it has not been supported …
I hope that clears things up.
Phil
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It’s a bit disappointing as any compliant CD player is supposed to support de-emphasis so I would have hoped it would be supported on Rossini Player/Vivaldi One if not when using a transport and the separate DAC.
Thanks for the confirmation, though.
Ha! I think I’ll check whether a few of my older CDs that sound pretty awful - thin and bright, and worse than I remember from when I had a non-dCS player - have pre-emphasis. I agree with BillK that it is a bit disappointing to have lost that feature, especially from kit that costs as much as it does.
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Or maybe they are just thin and bright sounding CDs 
I wonder how your are going to check if they are or are not pre-emphasised though ?
Incidentally pre-emphasis was optional anyway and exists only in the CD standard as an available ( not mandatory) notification flag in the Q layer of the subcodes.
Rarely used in CD production it seems to have disappeared before the turn of this century.
Of course one useful thing coming out of this thread is the discovery ( at least me) that later versions of dbpoweramp have the facility to apply the de-emphasis characteristic to rips. This seems to require a normal rip then converting the result using the Music Converter app with appropriate feature selection.
Pete, I assume I can go back to dBpoweramp and it will tell me (about pre-emphasis, yes or no). I ripped most of my collection using EAC, including the discs I have doubts about, and a quick glance at the internet suggests EAC wasn’t totally reliable at recognising and dealing with pre-emphasis, if it did so at all.
If you care to scroll up a few posts there is a link from me to the dbpoweramp forum. If you read the thread it indicates the version needed and how to do it. Look for posts from “Spoon” as that is dbpoweramp.
The difficulty is that you will need to know before carrying out the flac conversion which tracks are pre-emphasised. Of course if you de-emphasise the wrong ones this will act as a tone control. dbpoweramp will not itself distinguish the two AFAIK . That us unless you are able to find something further ( which I will be delighted to hear).
Edit: When making the original rip dbpower amp shows pre-emphasised tracks. However my recollection is that you only get this view at the conclusion of the ripping process. So I don’t understand exactly how practically useful this is.
You might (both) find this old thread with some good input from @miguelito over on AudioPhileStyle helpful. He suggests a couple of ways to check if a rip is pre-emphasized from the quick-and-dirty to the slow-and-certain.
Simon, I believe EAC did read the de-emphasis information, but only from the TOC, not from the subcode (which is how a CD-player reads it). Hence the risk for discrepancies and perceived unreliability. XLD is a reliable ripper that reads both. There is a feature comparison between rippers on HydrogenAudio which covers pre-emphasis among other features, although unfortunately it does have some gaps:
https://wiki.hydrogenaud.io/index.php?title=Comparison_of_CD_rippers#Pre-emphasis_detection
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