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As I understand these digital upconverters (such as the dcs),
they use an interpolation function to generate a high freqency
data stream from the standard 44.1 kHz CD data stream.If my understanding of the process is correct, something seems
philosophically wrong with this to me. It is easy to believe
that there may be more detail and a sujectively better sound,
but it does not represent the real high frequency signal that
existed when the recording was made.It seems like colorizing a black-and-white photo. Yes, it makes
the representation more "real" since the world is color, however
the photo does not represent a scene as it ever existed in the
world.Am I wrong about this? Or is this a worry that others share?
I have never heard an upconverter so this is just theoretical.
I believe you have heard a lot of upsampled DAC. Most CD players are upsampling now. Is is cheating, I don't know. It is just like amplication, why we need amplifier to increase the signal if someone can design a DAC that can drive a speaker directly.Paul Lam
P.L.C.Lam Consulting Inc.
Cheating? Yes and no. First, remember we are dealing with numbers here, not an analog signal. As I understand it the same mathematical theoums that 16/44 CDs are based on allow these upsamplers to place more data points between the original points. Whether this helps the digital filtering or something else, I can't say. Instead of colorizing a movie, which is purely subjective, the analogy is maybe closer to using Photoshop to sharpen up a digitized photo. Nothing is added, but clearer distintions are made between black and white in areas that used to be grey. Is it as good as true 24/96-no. Is it better than 16/44-sometimes.Others have said it is really little more than an extension of oversampling, with which we have all lived with since about the year 1 CD. In that case, it would appear that the benefit is being able to use a filter with a flatter slope, which yields a more accurate analog reproduction.
Bottom line: does it work for you?
One inmate's opinion.
Jeff Canaday
Maybe it is cheating in a sense, but I agree with John's posting that it has a desirable outcome. I use the purcell/delius (dcs) combo and I find that using it really improves the quality of the sound. How so? Cymbals are cleaner and clearer, more subtle detail is heard (I listen to a lot of jazz from the 50's and 60's so the details are things like shuffling feet, finger movement on a sax, etc.). Also, the soundstage is generally more precise (instruments are easier to keep track of). One mag reviewer referred to this type of improvement as taking a layer of cotton off of your speakers.
I've been a closet sceptic about upsampling since I first heard about it. To my simplistic mind you cannot create what is not there. Maybe this is correct but I'm guessing the main advantage is you longer lose what is there.I'm ignorant about the technicalities but the bottom line is that in the Meridian 861 it works very effectively in reproducing nice audio from redbook PCM. It is not quite as good as the best analog signal, but very close.
POeace at AA
John
One problem in evaluating upsampling in the change in equipment...I am sure some people hear a big difference between "simple" DACs and upsampling DACs, maybe it is due to the better quality components used in the upsampling DACs? I have an MSB DAC III with the upsampling upgrade...it is switchable in/out...after a weeks weeks of trying I cannot hear any decernable difference between sampling rates...changing speaker cables, changing sources and changing amplification have all resulted in big differences in my system...unfortunately (for me) upsampling has not...regards, tony
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