Huh? Plain DVD does 24/96? What's DVD-A for then?
Any DVD-A records with DRM?
All DVD-A discs are [currently] impossible to rip and force the digital outputs of the players to be downsampled. To me this is generally called DRM, but perhaps there is a specific meaning to DRM that I am not aware of.
Oh, I mean, any DVD-As without audible watermarks?
Audio Note Dacs are most famous of them: http://www.audionote.co.uk/dacs/dac_index.htm
If i am not completely mistaken the same is valid for CDs also, as red book forbids 0 dB 20 KHz signals AFAIK .. else no modern CD player could fulfil red book with a normal 1 bit DAC, even at high internal clock.
I don't understand any word.
For what it's worth, Audio Note is the most expensive hifi manufacturer in the world.Their top amplifier (100W vacuum tubes) is more than 150,000 $/€
Sounds good... the analog filtering should not lead to pre-ringing, unlike digital...
.. arent most modern DACs using a combination of digital and analog filtering to overcome antialiasing probs ?All the 'oversampling' stuff coming up in the early 90is had nothing to do with what oversampling really is ( during recording ), but the attempt to replace (expensive ) analog filtering with ( cheaper ) digital filters, thus making the analog filters more or less redundant .....
Can somebody tell me once and for all whether pre-ringing is actually an artifact or it is just the natural product of the calculations?
E.g. if you made a 2-way IIR brickwall filter (not 1-way, that would of course give no pre-ringing but wouldn't have correct phase response) that processes the whole track offline, would it still have pre-ringing?
About non-oversampling filters, I have to say that any DAC is supposed to filter as much as possible over half the sampling rate, otherwise you get lots of aliasing above this frequency. This is ultrasonic sound not audible by ear, but if at high levels, may intermodulate (because some equipment is more non-linear above audible range) and cause products that fall into audible range.So, proper DAC MUST filter over half the sampling frequency (over 22.050 KHz for CD), otherwise the DAC is lacking the necessary reconstruction filter.
KUSUNOKI SAN:There is a slight possibility that a digital filter-less DAC's intrinsic quantizing noise, existing beyond the audible range, can badly influence the sound. In my experiments, however, the noise is effectively eliminated with a first-order low-pass filter.The original Compact Disc format was based on the assumption that a "human can hear up to 20kHz" in essence. So why bother oversampling and cutting off the "inaudible sounds" generated by oversampling? I hope my readers to be skeptical on this methodological inconsistency.So, what is the sampling frequency in essence? Sampling the sound with 44.1kHz means that the CD can "differentiate the sound up to 25 microseconds." Raising the sampling frequency to 96kHz, for example, should not be considered as an extended frequency range up to 48kHz; it should be regarded as an "enhanced precision - over time domain," instead.TNT-AUDIO:There are studies showing the human ear sensitivity is extended to frequencies higher than 20kHz, at least in dynamic situations. This seems to contradict your theory. Our ears, anyway, tell us that you cannot be far from being right. What do you think about this? KUSUNOKI SAN:My theory is based on the assumption that our audible range is limited to 20kHz, as I have explained in the Audio Amigo interview. Therefore, if we can hear the sound beyond 20kHz and be influenced by it, this would be inconsistent to my theory.TNT-AUDIO:On the other side there is an audible loss in high frequencies, a few dBs at around 20KHz. According to you, is the drop in high frequency response an advantage or a shortcoming?If you consider this a limiting factor, have you ever tried to solve it? KUSUNOKI SAN:Certainly there is such loss when you measure the frequency response. However, the loss can be detected only by those people who are very sensitive to high-frequencies, and most listeners cannot differentiate the attenuation of sound. The loss is not favorable, but I think it is not that important.
About superiority of analog filters over digital filters, etc, any filter response, including analog, can be realized using digital filters, in a more easy and less problematic manner. That means that you can use digital filters at a DAC that show no pre-ringing the same way that an analog filter woud do, but with the consecuence that it won't be linear phase anymore, as analog filters.
KUSUNOKI SAN:I have been paying attention to the digital filters these days. I have described my DAC design as a "non-oversampling" in the MJ articles, and the appellation got out of control thereafter. Among those DAC components, the digital filters should be more important -- that's what I think at this moment.
This doesn't mean that if you let pass lots of high level ultrasonic garbage, due to the lack of a reconstruction filter, there is not going to be problems over the audible range. Most amplifiers have a passband that goes up to 100 KHz. If you let happen that ultrasonic garbage to pass from 22 KHz to 100 KHz, there is a good probability that with such high level ultrasonic signals, the usually greater nonlinearity of the amp at such high frequencies causes intermodulation products that fall into the audible range.
Again, I don't see any problem with today's cd oversampiling digital brickwall filters, in theory. In practice, if some phenomena not taken into account happens, well, show me some proper ABX or double blind tests that prove there is really a problem.
In my opinion, Kusunoki is another of those "illuminate" people who sell expensive esoteric solutions to solve unexisting problems. Same happens with things such as upsampling external DACs, SACD, even things like green pens, cd demagnetizers, cable holders, silver cables, etc.
P.S. maybe we could say that an oversampling DAC gives "tonal purity" while one without a filter gives " transient accuracy".
1. Brickwall filterImplemented as a digital filter. Usually used with synchronous oversampling. You cut off all information from the the digital signal after c. half the (over)sampling frequency. Pitfalls: ringing - with a simple single pulse the pulse will start to sound before it is played, because the filter "sees the signal before it is played". Most implementations also ring after the pulse is played. Some call this smearing in the time domain. One could say that this implementation is more correct in the frequency domain.2. Filterless DACYou don't cut off (or even attenuate) the alias images predicted by Nyquist theorem by filtering after c. half the sampling frequency. You get alias images right after half the sampling frequency and multiples of that. With CDs these mean ultrasonic noise in the analog signal. If implemented properly, you don't have ringing like with digital brickwall filters, but you do get ultrasonic noise. One could say this implementation is more correct in the time domain.So it's either frequency or time artifacts. Pick your poison.