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Upsampling CD players - black magic??

noeluk2

Member
I've recently purchased a Naim DAC. As well as feeding it high resolution digital files, I'm wondering if it would breathe into my old CDs, which requires a new CD player as my old CD5X doesn't offer a digital out.

It feels like a bit of a waste splashing out on another Naim/expensive transport when I have the DAC...

Should I consider something like the Cambridge Audio Azur 740C that can upsample the signal to its digital output?

Has anyone tried the 740C? What do we think of upsampling? A worthwhile practice or digital hocus-pocus?

Thanks!
 
Got a laptop? Try that first..
Then try ripping a cd or two into flac using dbpoweramp and playback using something like mediamonkey from the laptop through the DAC..
 
Could somebody explain the difference between over-sampling & up-sampling please?
:D
 
Hi Sam-cat.

Why, does dbpoweramp upsample when ripping?
It doesn't unless you select it in the ripping options and if you did then it would not be a bitperfect rip.
You would rip in native format ie 16/44 then upsample the rip in your media player.
 
Could somebody explain the difference between over-sampling & up-sampling please?
:D

The two are interchangeable, as pretty much there is no standard definition for either of them. Up-sampling has in recent years tended to be used to describe none integer processing ie 44.1-96khz and over sampling used for whole number processing ie 44.1- 176.4khz.
 
I am not sure if the bit depth and sample rate can be changed for flac. But it can be done with wave.

1. Change the rip to option to "wave"

3.jpg
'

2. The change the bit depth to 24 bit

2-1.jpg


3. If you need it in flac, then change the file from wave to flac after the ripping is completed.
 
If you're just using the cd player as a digital transport - for its digital output, not analogue - then you don't want upsampling.

Leave the naim dac to do whatever it wants with the original raw data. Don't have two sets of processing fighting each other. Let your naim dac weave its own magic - that's why you bought it. Just feed the dac with unmodified 44.1k/16 data
 
Upsampling does not increase the resolution ,it just adds 0's and 1's there are no benefits, it is not the same as a file which has been recorded amd mastered in a high resolution format.
Keith.
 
I remember attending a demo for Weiss 202, the dealer were using a software to upsample the music in real time. I have forgotten that the name of the software ...
 
The supposed benefits of upsampling come in the digital to analogue conversion stage where it was easier to convert the higher bit rate to analogue without audible artifacts if you didn't need the brick wall filters set at 22khz (half the sample rate). The original CD specification pretty much used the lowest sample rate possible to give a 20hz to 20khz response. Any lower and you can't filter out the digital artifacts, or are unable to quote the all important 20hz to 20khz specification CD had to have to be a marketable rival to vinyl. There are those that argued that 48khz was a better option because the additional 2khz headroom (filter set to 24khz) made it truly transparent, while 44.1 made the filter simply too close to the 20khz limit. Remember though that this is the 'academic' argument. The reality was that they got very good at doing it very quickly, upsampling being one of the tools, improvements in the filters were another route. Suffice to say it simply isn't the technical issue it was back in the early days.
 
The two are interchangeable, as pretty much there is no standard definition for either of them. Up-sampling has in recent years tended to be used to describe none integer processing ie 44.1-96khz and over sampling used for whole number processing ie 44.1- 176.4khz.

Exactly! Over-sampling has been around since the inception of CD but some people seem to think that up-sampling is a bad thing. Are they saying that because the process is fractional - it's bad? If those same people argued it was pointless, then I could understand their PoV without necessarily agreeing with them.
 
OK, so I guess I got this wrong. My oversampling and up sampling definitions are completely wrong.

I've just done a bit of googling to put me straight, but for your amusement...

I thought that ripping a CD to a larger resolution file didn't upgrade the signal, just held it in a larger container (topped up with blank space/lots of digital 0's??). It would be like pouring half a pint's worth of data into a pint size container. There's the same amount if beer, it tastes the same, just takes up more space on the shelf.

Whereas upsampling was where extra relevant data was kind of guessed/assumed based on surrounding samples, and then added between each sample to pad out the data. Like transferring the beer to the larger pint drop by drop, and adding something you thought tasted the same between each drop. Result = full pint of beer with a different character to the flavour.

I guess you can see how I got there.
 
OK, so I guess I got this wrong. My oversampling and up sampling definitions are completely wrong.

I've just done a bit of googling to put me straight, but for your amusement...

I thought that ripping a CD to a larger resolution file didn't upgrade the signal, just held it in a larger container (topped up with blank space/lots of digital 0's??). It would be like pouring half a pint's worth of data into a pint size container. There's the same amount if beer, it tastes the same, just takes up more space on the shelf.

Whereas upsampling was where extra relevant data was kind of guessed/assumed based on surrounding samples, and then added between each sample to pad out the data. Like transferring the beer to the larger pint drop by drop, and adding something you thought tasted the same between each drop. Result = full pint of beer with a different character to the flavour.

I guess you can see how I got there.

There are some very helpful, completely BS-free, threads and articles over at Hydrogen, if anyone is genuinely interested in learning about this stuff and not just parroting the mis-information.

http://www.hydrogenaudio.org/forums/index.php?act=idx
 


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