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I'm in the process of finalizing the authoring of a DVD-Audio disc containing test signals. If anyone is interested, please let me know. I would also welcome suggestions on format and content. I'm planning on making this disc available (plus full instructions on how to use it) for about US$10-15 - is this a reasonable amount to ask (I have spent a LOT of time on this, and you will appreciate the cost is basically to cover my effort in copying and shipping the disc, I don't think I'll get rich on this!) As a comparison, the CBS Test CD (containing only a subset of the signals I intend to offer) typically sells for US$45.What will the disc contain?
- Full set of all test signals from the EIA 560 standard (with the exception of the pre-emphasis test tones which are relevant only for CD) plus the additional two tracks suggested by CBS
- Audio Rightmark calibration and test tones, to allow you to use Audio Rightmark to measure the performance of your player
- Full set of signals suitable for testing for player handling of 0dBFS+ waveforms, in accordance with the AES paperAnd best of all, the above test signals will be presented in multiple resolutions (stored as different groups): 44.1/24, 48/24 and 96/24. I'm not planning on 192/24 at present, but interested in your feedback.
All test signals will stored as uncompressed (linear) PCM on the disc - no MLP will be used.
The disc will not be CPPM protected or watermarked.
As a bonus, I'm also thinking of including a group containing multichannel 5.1 test signals (at 48/24) suitable for speaker level setting, frequency response and phase measurement. Finally, you can calibrate your DVD-Audio player based on an actual DVD-Audio disc rather than based on compressed audio!
I'm also thinking of making a CD version of the test disc, containing the same content (plus the pre-emphasis test tones) available. Quite possibly the CD and DVD-Audio could be packaged as as two disc set, or perhaps sold separately. I can also make a DVD-Video version available (but only 48/24 and 96/24 since DVD-Video does not support 44.1/24).
Each test signal has been meticulously mastered for maximum accuracy and minimising quantization error - so I can guarantee that a sine wave at -80.77dB will actually be that level rather than somewhere around the vicinity. I have found a technique for doing this that yields better results than most of the software based signal generators I've played with.
Anyway, your feedback and potential interest will be appreciated. My apologies to the Bored for the slightly commercial nature of this post - I can assure you I'm doing this primarily as a labour of love rather than a serious intent to push my "products."
Follow Ups:
Yes! I would like this very much!Nobody seems to think about equipment tests anymore, only speaker tests, but I like to analyze distortion in various ways, starting with THD and THD+N. For high frequencies, the my LAUD/Fiji analyzer won't cut it, and I have to use a slow HP analog spectrum analyzer instead. So what I want is:
Sine waves that last a while, not just 15 sec (I hate those), but 1-10 minutes for a good slow spectrum scan.
For example, 1Khz for 5 minutes would be very nice.
Also, some higher frequencies, starting with 20K - 30K. 1 minute apiece would be OK.
Also, a good 19+20Khz "IM" test, for at least 5 minutes so I can scan deep into the millihertz. Make it 10 minutes if possible. This is a great test! Nothing is "perfect" on this one.
Also, a linearity test at 0, -10, -20, -30, -40, -50, -60, -70, -80, -90, -95, -100, -105, -110, -115, -120, -125. This could all be at 1Khz, each for 1 minute.
I've been getting so fed up with the typical 15 sec test tone disks, I've been thinking of burning my own 80 minutes of 1Khz CD.
One more thing50Hz for 10 minutes. John Atkinson always includes a good 50Hz scan, it shows lots of harmonics and potentially power supply problems.
so I hope you're still reading this thread :-)1) LSB tone (kinda like the NAB test disc); 1 LSB @ 24,48, 96 kHz. Perfect for testing player S/N ratio without allowing the DAC to mute. Well, OK, the tone itself will contribute to the noise, but at what is it, -144 dB, practically speaking it doesn't matter
2) 1 kHz or similar* tone modulated onto a very low frequency tone (0.1 Hz?). A Denon disc had this, and the VLF tone then caused the higher frequency tone to "sweep through all the bits" (my mental impression) and let you hear nonlinearities. (*maybe 400 Hz is less painful?)
3) A better noise modulation signal than the Stereophile test CD. Those tracks are cool, but way too short. (John Atkinson told me due to total disc length problems). They don't allow enough settling time for the filters on an Audio Precision to average.
4) some kind of "BOOM" with a long smooth reverb tail. Don Dorsey's "Ascent" on Telarc once let me show some "don't they all sound the same" unbelievers why the Magnavox CDB-650 I had at the time was superior to all the other stuff sitting around at work. You could clearly hear big differences in the LF reverb tail.
Good luck, and if you actually get into production reply below so I can see your message!
Cheers,
H.U.
Have you used and compared the DVD-Audio test disc from Chesky?
If that's what you want, go for it.I'm talking about a disc filled with nothing but test tones, comforming to a superset of the EIA 560 (also CES 560) standard for measuring digital players. These include tones for testing for frequency response, pitch accuracy, intermodulation distortion, dynamic range, etc.
In addition, there will be additional test tones that will allow you to determine whether your player will distort upon encountering 0dBFS+ signals. There will also be log sweeps to allow you to measure impulse response.
In other words, this disc will NOT contain music. If you do not have the knowledge/interest/equipment to measure your player or your system, then I would suggest this disc will NOT be useful to you (except perhaps for aligning speaker levels).
But unless I seriously make an effort to borrow a friend's spectrum analyzer, I probably wouldn't benefit much from such a disk. If you happen to come up with such a disk, I might get it for level-matching. Otherwise, I probably won't benefit from it much.I'd ditto other comments about the possible usefulness of 24/192 soundtracks. Otherwise, there's a slight "intellectual interest" which falls by the wayside when considering enjoyment of music and/or movie content playback.
Clear as mud ? :0)
Like Charles Hanson, I am intereted in a disc with 192k/24 bit signals; the rest is fine.
I'd be interested in this disc and would order multiple copies. I'd really like to see a 192/24 group -- I think this is quite important. If you have enough time, I'd also suggest including 88.2 and 176.4 kHz just to be complete.
. . . how did your tests go with the AIX disc in your Ayre C-5xe hirez- stereo universal player?
The short answer is that the C-5xe will play what you want on the AIX discs. Just go to Group 2 by pressing the "2" button on the remote when the disc is stopped.The long answer is that there are four groups in the DVD_Audio TS:
Group 1 = 96/24 MLP 5.1 "Audience" Mix
Group 2 = 96/24 PCM 2.0 Stereo Mix
Group 3 = Dolby Digital 5.1 "Audience" Mix
Group 4 = DTS 5.1 "Stage" MixAll of these will play on the C-5xe, with the multi-channel versions being downmixed in the player to stereo.
The wacky thing is that there are also two separate Soundtracks within both Groups 3 and 4. These are 96/24 PCM stereo tracks, although I would assume that they are different mixes than what is found in Group 2 (I didn't listen). Even crazier is that both Groups 3 and 4 default to Soundtrack 2. This is correct for Group 4 because the DTS track is there, but the Dolby Digital track is on Soundtrack 1 of Group 3, so the only way to listen to it (presumably on any player) is to manually navigate to Soundtrack 2.
The DVD_Video TS appears to have the same content as the last three groups (of course the MLP is not valid for DVD-V), partitioned into Titles 1 - 3. The exact same navigational quirks as described above are there also.
I don't know how the data is stored on the disc (which was a separate question from the old thread).
Charles,That's quite interesting what you report, and I'm sure your information will be useful to owners of that machine (or prospective owners) who are reading this. (i.e. it is possible to play any group and track on a DVD-A with the C-5xe.)
By the way, regarding the LPCM stereo tracks which appear as if they are duplicated on Groups 3 and 4, what I think is the case, is that these are just ‘references’ to the same underlying data. I don’t think that Dr. Mark Waldrep could have made so many duplicates of uncompressed LPCM and have them all fit onto one single layer DVD-5, along with the MLP 5.1, Dolby 5.1 AND DTS 5.1 content! ;-).
And when the player is set to DVD-Video mode, likewise, I think it’s still just referencing the one underlying LPCM data track, i.e. I don't think Video_TS is duplicating it.
and list the contents of AUDIO_TS and VIDEO_TS directory? Can you also run DVD Decryptter/DVDAExplorer and let me know the structure of the AUDIO_TS and VIDEO_TS content?I'm very interested to know, because i haven't been able to link into VIDEO_TS from the DVD-Audio structure. Wavelab doesn't support it, and the version of Chrome I have does an "import" rather than "link" (ie., it copies the stems and duplicates the content).
I noticed Neil Wilkes is having similar issues since he's posted a message about this in the Wavelab support forum.
. . . at the structure of the AIX Scarlatti disk . . . and e-mailed screenshots of the Audio_TS & Video_TS directories to you. I'm sure you can make more sense of them than I can.b.t.w. I also tried to look at them in the tools you mentioned, but the DVDA tool only shows the MLP files in Audio_TS; while the other DVD-V tool won't read anything at all in Audio_TS. So neither are any help when looking for LPCM files which may be duplicated in Audio_TS.
You can post here or e-mail me what your findings are . . .
You can link DVD-Video and DVD-Audio content by using multiple VTS sets and using a VGM menu to link them. The basis is to author one project first (DVD-Video usually), compile it, then import it with a link from the DVD-Audio project. You need software that supports this though.
*** You need software that supports this though. ***That's the real issue. I haven't come across documented evidence of an authoring tool that supports it. I've also yet to see hard evidence of an actual commercial disc that implements linking (as opposed to duplicated content).
I understand there's some fairly severe restrictions that constrain whether the link will work or not.
Neil Wilkes said the current version of Chrome should support it, but I asked him to do a test DVD to demonstrate that it works and so far haven't heard from him.
DVDLab Pro supports the importing of pre-compiled VTS content, but that would mean you'd have to author the DVD-Audio first, then the DVD-Video so that would prevent AUDIO_TS to VIDEO_TS linking, you could only do VIDEO_TS to AUDIO_TS.> I've also yet to see hard evidence of an actual commercial disc that implements linking (as opposed to duplicated content). <
There are a few, but I forget which. I seem to remember there were some discs with 96kHz PCM that was available to DVD-Video players that was actually in the AUDIO_TS folder so that it couldn't be ripped (prior to the DVD-A hacks). That at least cuts down on disc space to a certain degree, the two-channel content can be shared.
> > "There are a few, but I forget which. I seem to remember there were some discs with 96kHz PCM that was available to DVD-Video players that was actually in the AUDIO_TS folder ..."discs from the Hi-Res Music catalog.
DVDLab (Pro) is a DVD-Video authoring tool - it does not understand the AUDIO_TS structure. Try it yourself - you cannot import any DVD-Audio content, not even unprotected ones.*** I seem to remember there were some discs with 96kHz PCM that was available to DVD-Video players that was actually in the AUDIO_TS folder so that it couldn't be ripped ***
I don't think this is possible, but happy to be corrected on this. The DVD-Video spec predates DVD-Audio, so there is no provision to link into AUDIO_TS content - and DVD-Video players do not contain the logic to parse AUDIO_TS.
All the discs that I've encountered so far with LPCM content on both DVD-Video and DVD-Audio turned out to be duplicates rather than linked content.
You can just import an entire DVD structure with any tool, only specific VTS sets. The key is to do that when authoring the DVD-A content. You can then link to it in DVDLab pro by writing your own links (just trying to drop an AUDIO_TS set into the program will not work, of course).
no, AUDIO_TS has a *different* structure - doesn't use VTS or VOB, therefore not recognisable by DVD-Video authoring tools.
Hi Christine,I'll see what I can do. I do have numerous AIX titles -- DVD-5s -- which use the same authoring, including MLP, DTS, Dolby, and LPCM mixes like the Stravinsky disc which Charles Hanson has.
A while back, I did download the DVD-Decryptor stuff out of curiosity, and I'll see if I've still got them on my hard drive somewhere.
b.t.w. I could be wrong about these discs not duplicating the LPCM in Audio_TS and Video_TS, I did ask Mark a while back, but I never got a straight answer!
However, I still find it hard to believe they could do that from a space standpoint.
Thanks. look forward to your observations.*** However, I still find it hard to believe they could do that from a space standpoint. ***
You can probably do the calculation yourself. One DVD-5 can contain around 6 uncompressed CDs. LPCM96/24 takes slightly over twice the data storage, but if you compress it using MLP then it takes around the same space as 1 CD. So in theory you can fit about 6 MLP 96/24 2.0 tracks on one DVD-5.
MLP 96/24 5.1 takes about 1.5 * uncompressed CD.
I really would like to see solid evidence of a DVD-Audio with proper linking to VIDEO_TS since all the discs that I have seen so far contain duplicated content rather than linking. Maybe that's a limitation of current generation authoring tools, I am not sure.
It's possible that this disc is a dual-layer DVD-9. When I was looking at the various Groups, there were some navigational changes that took a longer time than others, suggesting that a layer change was involved.
-- as are all the other "Bucharest Session" AIX DVDAs -- it would be recognisable as a DVD-9 if it had two-concentric barcode rings. If, however, it's a DVD-5, then just one barcode ring at the center ring is usually present. (At least with the discs I've seen to date.)Also, double-layered sides are sometimes gold-colored, while single-layered sides are silver-colored, like a CD.
.
The video_ts content is linked through group 3 and 4.The content in the video_ts is not authored as DVD Audio.
The answer may be to use a 24 bit or 48 bit software based signal generator attached to a good FFT program (not Rightmark which gives better results than proper FFT programs). Save thes in .wav and burn to DVD Video. The results can be checked on the computer 192k may be a problem though as DVD Audio burning software will be needed.
In fact, with your permission, I am happy to replicate the signals you use in your "Irrational But Efficacious" disc - that can be in a group by itself, and I can even do it at whatever resolution you want. If you send me the exact specs for the signals (including track length), I'm sure i can replicate them using my method (below).I've discovered that most signal generators are not very accurate at low levels, esp. below -60dB, due to quantization errors generated by the fixed point algorithms. For example, I found generating a sine wave at -59.94dB resulted in a wave that didn't even track at -59.94 - it was off by as much as 1% (very significant for test and measurement purposes). I had to devise a different approach that yielded a waveform that measured at -59.941dB (well within spec). In fact, all the waveforms i generate are accurate down to 0.01dB resolution (even at -100dB, which is the lowest level i try to generate).
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