Upsampling by dac, can't hear an improvement.

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11 hours ago, jabbr said:

1) There are outstanding examples of software upsampling to both R2R based and SDM based DACs.

2) upsampling PCM to a SDM DAC might not have a benefit. 

3) The DAC in question is not typical and benefits of offboard upsampling depends on the DAC being able to accept.

4) Only rarely does something work for everything.

 

I think your DAC does internal PCM->SDM conversion as so if accepts DSD in, that might be better 

 

Came here for that. When the DAC has its own internal filter, the upsampled data is "shaped" by the filter and should look very similar to the original filtered data. 

 

With the R2R on the Lampizator, upsampling does have a perceptible difference. Perhaps not to the point that one could easily spot but is noticeable. But I can certainly spot the difference between playing nos and upsampled to DSD (using the 2nd engine). Just the other day I thought the sound was somewhat changed from one day to the other (!) and indeed I had disabled upsampling - I don't think I would be able to tell the difference if I was comparing PCM streams. 

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28 minutes ago, Lebouwsky said:

I think we're on the same boat when it comes to upsampling PCM. But when it comes to upsampling PCM to DSD I have no experience.  I recently invested in good PCM dac. When you discribe the PCM tot DSD upsampling as "somewhat changed" I don't feel the need to go DSD real soon. What's your opinion about PCM to DSD?

 

I haven't heard other DSD DACs that are capable of playing native streams without any kind of conversion. I think the Lampi is quite unique when it comes to DSD implementation and theyre certainly one level above the mainstream (t+a is another example of a dac praised for is Dsd). I have heard one or two other DACs where DSD was not all that great.

 

Mind you that the Lampizator actually has two separate circuits which share the same interface and clock, therefore  the difference may not be only due to the digital stream but due to the implementation as well. As fellow ? ? just wrote, another DAC may have a better R2R circuit (I'm sure there are better face in this respect than the Lampi) but not a so good DSD engine and the result may be the opposite. Just stick to the one which sounds best on your equipment...

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1 hour ago, jabbr said:

 

The standard format for CDs is PCM. The internal format for most ADCs and DACs is SDM/DSD. Many DAC chips are very complicated and first upsample/convert PCM to DSD/SDM internally before converting to analogue. In these cases there can be a benefit for outboard conversion to DSD as this step is math intensive.

 

Other DACs which are truly native PCM are called R2R based on the resistor ladder. These DACs have no benefit to outboard DSD conversion. 

 

I use  @Miska'S HQPlayer for  outboard DSD conversion (DSD512) and either HQPlayer or @PeterSt XXHighEnd for PCM upsampling before feeding into the DAC (up to 700 kHz range). I find this makes a terrific improvement for me with CD source in particular.

 

DACs that won't bypass their own internal filters and preprocessing units would not be expected to show the same improvements with outboard upsampling. Does your DAC have an R2R ladder? Does it accept DSD input? If it has an R2R ladder then you don't want to convert to DSD. If it doesn't accept DSD in then you can't. Otherwise worth trying.

 

Correct, many DACs which accept both DSD and PCM will first convert to their native input (mostly PCM) which is only then converted to 1 bit before the SDM. Converting a PCM stream to DSD in this case is kinda pointless. 

 

Without a conversion chip, a R2R cannot accept a DSD stream - what the Polish guys do is to divert the DSD streams from the ladder to the DSD circuit.