You haven't used HDCD.exe obviously. HDCD encodes two things: peak limiting/extension and filtering. The HDCD.exe can report if the filtering is encoded but the guy who hacked M$ WMP9 was unable to hack the filtering portion. It may be that this was dropped with the PMD200 and WMP and the PMD100 is the only full implementation. Just read the HDCD datasheet from PM.
And yes HDCD.exe is 100% black market and is a breach of M$ licensing. I think the going rate is $25k to get licensing and the full code .
Hi,
Filtering is only relevant if digital filtering is employed. I use non-os DAC's and no filtering and I do not use software upsampling.
That is because WMP9 does not oversample.
I am quite familiar with HDCD and the datasheets (and more).
Actually, reverse engineering a piece of software and writing new code that does that same and making this code (and compiled binaries) available is not black market (especially if the software is released as free software).
As for paying M$ for the licence, you just go and try to get them to accept your money. The problem with the HDCD licence is not the money, but the fact that M$ has zip interest in actually getting this revenue... ;-)
Ciao T
Filtering is only relevant if digital filtering is employed. I use non-os DAC's and no filtering and I do not use software upsampling.
That is because WMP9 does not oversample.
I am quite familiar with HDCD and the datasheets (and more).
Actually, reverse engineering a piece of software and writing new code that does that same and making this code (and compiled binaries) available is not black market (especially if the software is released as free software).
As for paying M$ for the licence, you just go and try to get them to accept your money. The problem with the HDCD licence is not the money, but the fact that M$ has zip interest in actually getting this revenue... ;-)
Ciao T
Its absolutely a patent infringment to implement HDCD encoding in a commercial product without paying M$ for the licensing. I know because I tried to get AudioGD to include it in their DSP-1 filter, they said M$ wanted $25k. And they do license it to several manufacturers, so there is interest.
You may be right about the filtering but others disagree. I just stick with my PMD100 DAC for now.
You may be right about the filtering but others disagree. I just stick with my PMD100 DAC for now.
Hi,
Expired patents cannot be infringed.
M$ nowadays only deals with huge manufacturers, this means the typical High End manufacturer is simply not being served by M$, so the only real market for their product is actually one M$ is not interested in.
By all means do. I stick to hdcd.exe... ;-)
Ciao T
Expired patents cannot be infringed.
M$ nowadays only deals with huge manufacturers, this means the typical High End manufacturer is simply not being served by M$, so the only real market for their product is actually one M$ is not interested in.
By all means do. I stick to hdcd.exe... ;-)
Ciao T
I tried it myself and asked in the forums whether it was an indicator light or a decoder. You can see a photo of the control panel with HDCD enabled here: New Musiland Driver. With HDCD Decoder? H I F I D U I N O
I had ripped a HDCD CD where I knew one of the 10 tracks was NOT HDCD (as indicated by a Denon-HDCD capable player). The Musiland driver correctly identified which of the 10 tracks was not HDCD.
I am not sure what kind of implementation it uses, but it is implemented in the driver and it decodes on the fly. In any case, the patents would expire in about 1 year and everyone can implement it by reverse engineering.
BTW, it is not so much that HDCD.EXE does not take full advantage of HDCD but that most HDCD recordings do not take full advantage of HDCD. Thus HDCD.EXE will probably handle correctly most if not all existing HDCD recordings.
Update: Musiland discourages the use of the feature. According to one post: "HDCD functionality has not passed Microsoft authorization, there may be copyright issues, use is strictly prohibited". The driver is beta software and HDCD is disabled by default (but it is there if you want to experiment)
There is hope the implementation is "official". Perhaps the market that Musiland is addressing (China) is big enough for Microsoft to license the HDCD code.
There is hope the implementation is "official". Perhaps the market that Musiland is addressing (China) is big enough for Microsoft to license the HDCD code.
For those of you who don't understand what "black market" means this quoted post pretty much sums it up.
Its crazy to think M$ doesn't care about patent infringement on anything, if they do that, then they lose all their patent license enforcement on everything. This is one of the first things they teach you in law school (and I'm just a dumb engineer.)
Most advantages of HDCD will be ONLY with hardware implementation (PMD100) becouse HDCD has complementary filtration (the main function of HDCD)
I agree 100%, there is an advantage for the studios to use the same filtering algorithms with their ADC that you use on your DAC at home, to me that has always been the biggest advantage yet curse of HDCD. HDCD also gives the mastering engineer the control to change filtering on the fly depending on transients, instruments, etc. We talked that is 10 years or so we may have 8x44.1khz sampling rate computer transports and then all the advantages of HDCD could theoretically be programmed into the computer. You could basically use your computer to eliminate the need of a hardware filter. Hope this day comes at some point.
I apologize for not getting off this subject, its just that the original post hinted at a upsampling/NOS hybrid type DAC, I really like a lot of attention to detail and fundamental design being applied to NOS DAC's, but personally never liked the sound of NOS, it would be great if we could have a project that can do both and the PCM1704 is the ideal candidate.
Hi,
This is a fatally flawed argument. No filter at replay can "restore" lost information. Complementary filtering is not neccesarily the better choice, in fact often severely non-complementary filtering (apodising e.g.) seems the better choice, if filtering must absolutely be used.
I implemented a digital filter (and upsampling as well) and analogue filters all switchable on the fly to give people the chance to choose. I know of no customer or reviewer who ever preferred using any of the digital filters consistently (most use them very rarely).
It may be interesting to explore the why. Which DAC's that are non-os have you heard and in what system context?
Ciao T
This is a fatally flawed argument. No filter at replay can "restore" lost information. Complementary filtering is not neccesarily the better choice, in fact often severely non-complementary filtering (apodising e.g.) seems the better choice, if filtering must absolutely be used.
I implemented a digital filter (and upsampling as well) and analogue filters all switchable on the fly to give people the chance to choose. I know of no customer or reviewer who ever preferred using any of the digital filters consistently (most use them very rarely).
It may be interesting to explore the why. Which DAC's that are non-os have you heard and in what system context?
Ciao T
That's only if applied in the mastering. HDCD.exe can tell you (detect) if the filters have been used. The tracks I tried did not use the filtering
As far Im concerned, all Spoon records reissues are SACD...
(...)
I too read the hdcd patent. Apparently it has a 20bit 96khz multibit converter, I think its built around a residual ADC. IMHO it works like this:
sample&hold-> 8bit Flash ADC, signal converted back to analog via fairly accurate r2r DAC, result subtracted from the original signal, then the rest of the bits come from successive approximation, a highly accurate r2r DAC.
Maybe those LSB-s are hurt by the sample&hold, maybe not. Some opamps are definately there.
1. Differential nonlinearity must be very good, but hey, with SACD, that comes for free , too.
2. I don't think that filter selection thingie is all that important once you record at 96khz.
3. I suspect there was more DSP processing on PCM stuff than on SACD, and I consider that ( we are talking about 90's ) a bad thing, since it was very new. First digital consoles arrived in '87.
How about the pmd100 coefficients? Its an old chip, I think it must be around 24 bits , no?
(...)
I too read the hdcd patent. Apparently it has a 20bit 96khz multibit converter, I think its built around a residual ADC. IMHO it works like this:
sample&hold-> 8bit Flash ADC, signal converted back to analog via fairly accurate r2r DAC, result subtracted from the original signal, then the rest of the bits come from successive approximation, a highly accurate r2r DAC.
Maybe those LSB-s are hurt by the sample&hold, maybe not. Some opamps are definately there.
1. Differential nonlinearity must be very good, but hey, with SACD, that comes for free , too.
2. I don't think that filter selection thingie is all that important once you record at 96khz.
3. I suspect there was more DSP processing on PCM stuff than on SACD, and I consider that ( we are talking about 90's ) a bad thing, since it was very new. First digital consoles arrived in '87.
How about the pmd100 coefficients? Its an old chip, I think it must be around 24 bits , no?
Well obviously the filters you used that were switchable on the fly is important to know. Basically IMO there are only 3 ever made that sound right: PMD100, SM5842, SM5847. If you were using a newer DSP based filter or an ancient filter I wouldn't be surprised by those results. Basically 95% of what I listen to is mastered by Jeffry Norman or Steve hoffman, and their CD's just never sound as good on a DAC with anything besides a PMD100 to my ears.
It was a simple CS8412 TDA1543, no analog filtering. Various tube headphone amplifiers, Senn HD650's and AKG 271 headphones
The issue I had with that one and others I've bought is hard to explain. I noticed an increase in treble/upper midrange but a complete loss of high treble (over 15k). What I found by playing test tones was very odd. Listening to tones played up to 14khz were fine, higher than this I would get a tone that stayed at 14k, in other words a 17khz tone sounded the same pitch as a 14khz tone. I am assuming this was aliasing. The phenomenom obviously won't show up on a sweep measurement. Basically it just rubbed me the wong way.
I compared it to a PMD -AD1862 DAC that I built that was near identical except I added analog filtering (PS same design), didn't have this issue. And I fell in love with the PMD100. I've used it in all DACs I've built or bought since.
Personally I like the NOS designs on here with excellent PS, R2R DAC's, etc. Just think you may be surprised at what the PMD100 is capable of.
But I have a growing collection of well made 24/96 recordings and think that NOS may show some advantage (plus my PMD100's can't play them.) So I am keeping an open mind, would be nice to have one box though. It is just fustrating sometimes that we rarely have open source DAC projects with OS and R2R DAC's, its usually either NOS or Sigma Delta (which I also don't like.)
Thanks for asking for my opinion and by no means do I claim to have all the answers, we all hear things differently.
Last edited:
Hi,
The filters are in DSP, standard brickwall.
I agree with you that if filters must be used the PDM100 would be my choice, not sure about about the NPC Ones, though they are not bad.
Well, this is like the first Non-OS DAC I build in 96 or 97.
While the sound showed some promise (e.g. it had some positive qualities that the DAC do jour at the time lacked), the overall performance of this kind of DAC (even with large numbers stacked) is not very high.
If that is your only comparison, try listen to something that addresses source jitter (the Cirrus Logic chip's basically pass all of it) and uses DAC's that have the appropriate level of analogue performance for the signal you feed them. And make sure to employ a correct analog filter that employs sinc rolloff correction and a sensible reduction of images above ~ 50KHz.
Not at all. On HDCD's I preferred PDM100 & OS over Non-OS, but non-os (TDA1541, PCM63) for normal CD's. But that was before I was able to decode HDCD and play it non-os. I need to pull one of my old HDCD Players out of Storage and try again, once I have a 24-Bit Non-OS DAC (right now only 16 bit).
Ciao T
The filters are in DSP, standard brickwall.
I agree with you that if filters must be used the PDM100 would be my choice, not sure about about the NPC Ones, though they are not bad.
Well, this is like the first Non-OS DAC I build in 96 or 97.
While the sound showed some promise (e.g. it had some positive qualities that the DAC do jour at the time lacked), the overall performance of this kind of DAC (even with large numbers stacked) is not very high.
If that is your only comparison, try listen to something that addresses source jitter (the Cirrus Logic chip's basically pass all of it) and uses DAC's that have the appropriate level of analogue performance for the signal you feed them. And make sure to employ a correct analog filter that employs sinc rolloff correction and a sensible reduction of images above ~ 50KHz.
Not at all. On HDCD's I preferred PDM100 & OS over Non-OS, but non-os (TDA1541, PCM63) for normal CD's. But that was before I was able to decode HDCD and play it non-os. I need to pull one of my old HDCD Players out of Storage and try again, once I have a 24-Bit Non-OS DAC (right now only 16 bit).
Ciao T
Wow I didn't know NOS designers are now imploying sinc roll-off correction.
One thing to keep in mind is that on some rare but special HDCD's the software decoding doesn't take full advantage of the actual chip. But it does sound like you understand why it would be cool to have a DAC that could be switched from PMD100 to filterless.
Thanks for the info and I'm glad this didn't turn into a NOS vs OS bout 🙂
...wait, wait- we can still turn it into HDCD vs REALITY ... : ))
http://www.diyaudio.com/forums/digi...-decoder-project-post1964728.html#post1964728
Last edited:
HDCD is a PITA, and unfortunately you have to have a hardware decoder for the music to sound correct if you have HDCD encoded music. It fits the M$ business model so well that they bought the company!
Hi,
I don't know about "NOS Designers" as in general. I have used and advocated it since around '97 or so. 🙂
Ciao T
I don't know about "NOS Designers" as in general. I have used and advocated it since around '97 or so. 🙂
Ciao T
- Status
- Not open for further replies.