Upsampling bad?

Hi,

Tenson said:
So what do you think of dithering the bit-depth from 16 to say, 24?

Noise shapeing?

My experience suggests that dither below the LSB of 16-Bit signals is ineffective, no matter the resolution of the DAC, dithering the lower bits of 16-Bit signals does have an effect, if this is a positive one or not is a debatable issue.

What is usefull though is to take 20 or even 24 Bit and use dither in the process of reducing bit-depth. I feel that for example using 88.2KHz sample rate and 24 Bit bitdepth is a good idea in recording and mastering, then use software SSRC algorythms to get back to 16/44.1 and your losses should be minimal.

Ciao T
 
Strangley I'mg going to agree with Thorsen on this, I've always felt 88.2khz (twice red book) was the best trade off, and increasing the resolution rate I've never found detrimental. Have aplay with a big ben you'll know wheat I mean !!!
 
I have to say in my experience the bit-depth has a larger impact than the sample-rate. I find going from a 24 or 32 bit 44.1KHz recording to 16bit 44.1KHz has a larger difference than going from 96KHz 24bit to 44.1 24bit.

No comments on noise shaping though? Maybe that isnt a technical term. The DEQ2496 has a button called 'noise shaping', which it says does something to shift distortion from something or other to a much higher, inaudible frequency.
 
Hi,

Tenson said:
No comments on noise shaping though?

Noise shaping is an approach to take the quantitisation noise and shift it to "supersonic" frequencies, SACD is an example of agressive noiseshaping, it has less dynamic range and resolution at 20KHz than 16 Bit 44.1KHz PCM as a result, with telling sonic results, it also is at the core of making delta sigma DAC's work (and sound the way they do).

So, noiseshaping is best avoided, together with digital filters and all sorts of other stuff. Just sample at 192KHz/24 Bit using basic 2 X Oversampling in the AD and using averaging between adjecent samples and you can use very simple filters to remove aliasing and no Digital filter or DSP is needed anywhere.

Ciao T
 
3DSonics said:
The reason that ASRC's exist is that pro-audio digital recording routinely used 48KHz sample rate (since days long before the CD) and the CD has a sample rate of 44.1KHz. As there is no integer multiple between the two you need to do some fancy DSP to get from one to the other and get there you must, to get a CD from a 48KHz master tape.

Hi Thorsten,

I regularly do sample rate conversion from 48k to 44.1 in my Mastering studio and get GREAT results!

But then I do it via a Studer A80 1/2" @ 15ips :) .

To my ears all asynchonous sample rate conversions suck (including upsampling).

Regards

David
 
Hi,

dcathro said:
I regularly do sample rate conversion from 48k to 44.1 in my Mastering studio and get GREAT results!

But then I do it via a Studer A80 1/2" @ 15ips :) .

Consider upping the speed to 30ips (you can get kits to do that) and if you really want to get things going consider using a G36 and get it fully rebuils and serviced.

Certainly gives the term "Digital to Analogue Converter" another rather different twist and introduces an excellent source of natural and sonically inoffensive dither while we are at it.

Ingenious. Makes one wonder why not go AAD to start with... ;-)

dcathro said:
To my ears all asynchonous sample rate conversions suck (including upsampling).

Welcome to the club.

Ciao T
 
3DSonics said:
Consider upping the speed to 30ips (you can get kits to do that) and if you really want to get things going consider using a G36 and get it fully rebuils and serviced.

This is a high speed version, but personally I prefer 15 to 30. I have rebuilt the cards (mainly 0.1uf black gate bypass caps across the Tants for superior High Freq performance).

Certainly gives the term "Digital to Analogue Converter" another rather different twist and introduces an excellent source of natural and sonically inoffensive dither while we are at it.

Ingenious. Makes one wonder why not go AAD to start with... ;-)
Yes, unfortunately, digital is just too convenient for most people. I get very few projects coming to me on analogue. However the machines are still extremely useful.


Welcome to the club.

I also don't like digital filters, and have enjoyed reading your contributions on the NOS topic. I am in the process of building a high end NOS prototype cd player with a friend of mine.

Best Regards

David
 
I've heard the dCS,and liked the results of it's upsampling,and later bought a Perpetual Technologies DAC and Upsampler/Interpolator.

Used together,the PTech units are amazingly good for the price,especially if used with upgraded power supplies rather than the wall-warts they come with.
I now use the upsampler set to 24bit/96kHz with a TAG Av32R DP,with again very good results....the sound via the TAG is smoother and more open than without the upsampler,and certainly less edgy than it can be otherwise.

I think the point of all of these systems is that like with everything else,they work for some people and some systems,and not for others,and particularly so where the upsampling,and/or interpolation of data to 24bit word lengths,isnt done very carefully.
 
alexs2 said:
I've heard the dCS,and liked the results of it's upsampling,and later bought a Perpetual Technologies DAC and Upsampler/Interpolator.

Used together,the PTech units are amazingly good for the price,especially if used with upgraded power supplies rather than the wall-warts they come with.
I now use the upsampler set to 24bit/96kHz with a TAG Av32R DP,with again very good results....the sound via the TAG is smoother and more open than without the upsampler,and certainly less edgy than it can be otherwise.

I think the point of all of these systems is that like with everything else,they work for some people and some systems,and not for others,and particularly so where the upsampling,and/or interpolation of data to 24bit word lengths,isnt done very carefully.

Yes, basically, we listen in different ways, and and hear different things. It is what is important to you! I personaly would gladly sacrifice detail and separation for dynamics and musical coherance.

I haven't heard the PTech stuff, but I HATE the sound of DCS dacs and upsamplers.

David
 
Stereo Mic said:
Have you heard the new Integrated? Quite a different experience yet still upsampling (even to DSD)

I haven't heard it, but I doubt I would like it. DCS have a philosophy about what they are trying to achieve, and how they design their equipment. I don't think it is possible for them to build something I like.

Sometimes a company can come out with a different result by accident, but in my experience, things that I like have been acheived by deliberate design decisions, consistent with an underlying philosophy that is very different to DCS's.
 
:D :D :D

This reminds me of the arguments we used to have about multi-bit vs. bitstream :D

Then, as now, it's all down to the implementation. There are great DACs with upsampling and there are great DACs without it.

To generalise that upsampling kills the tune (or reduces involvement) is tosh. This is not universally the case.

Also, rhythm is no the be-all and end-all of involvement. Many other factors come into play and it probably varies from one musical genre to another. All hifi is a compromise, a blend of attributes. Some people prefer hifi that majors on rhythm, others prefer it to major on timbre, air, stage, etc. All of these things can be involving.

I am very happy with my upsampling CD player. The extra clarity and smoothness that it brings is well worth the loss of a little of the rhythmic involvement. My system was already tweaked to increase rhythmic involvement so I'm not losing much. It's still easy to follow a tune and remain engaged (entranced even).

My hihi journey is not over yet though. The Dynaudios have opened a new door and I am now wondering what else there is to be discovered.

Coherence...

...but that's another thread :D
 
Markus Sauer said:
Have you heard it? What did you think?


Yes Markus and it seemed perfectly competent.

I thought the imaging available whilst upsampling to DSD was at the same time spacious and focused, something rarely encountered I find. Tonally on the warm side of neutral perhaps but unlike previous incarnations, it did not seem to cause indifference through sonic fireworks.

I'd still take my CD7 to be honest though. For me, I have yet to hear a better all rounder despite it's age.
 
I have heard the dCS integrated, only briefly though. The rest of the set: Spectral amplification, Avalon Eidolon, MIT Oracle.

It didn't sound edgy, cold or so. It was really refined. Only one thing, it stayed a bit remote (in the sense of "not connected", I wasn't involved).
 
You guys sure have made me curious of the CD-7. I like the 16 bit NON-OS sound, but I find my Ack dAck a bit too 'busy'. Would CD-7 give me the same type sound, but with a better controlled presentation when the going gets tough? What does it use for a digital/analog filter? Any easy mods? I find this player very promising.

Might be the perfect step between the 'neat and tidy presentation' players and the 'warts 'n all' NON-OS DACs!
 
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