[Ryokan]

All but outdated R2R NOS DACs will turn a PCM signal into something like 3 to 5bit + massive oversampling. While DSD DACs if they're not a decade old will also use at least 2 bits (because a one bit system is just dumb, always was, and only made sense before we found another way). The actual processes end up being more similar than most people suspect.
You'll still find objective differences (even more so if the designer wants some audible ones to be found), but no more than what has always existed with all DACs and DAC chips. Difference in the final sample rate, difference in the filter (frequency and type), differences in how much of some upsampling event is used for anti jitter/reclocking action. I suspect that a bunch of those differences are there to avoid patent infringement, and not to try to reinvent the wheel.
I'm sure you can have fun oversampling anything up to DSD1024 equivalent or whatever, but why?

MP3 and flac are converted to PCM before being sent to the DAC/DAC chip. It doesn't change anything to what can or will be done with it.

I'm guessing people who are dearly interested in such discussions are already fans of the very special DSD "sound", or have firm beliefs about oversampling settings and how they "sound". But for us cardboard ears who never listen to anything and only look at graphs, it's rarely worth anything because if a device can benefit from oversampling/upsampling and the designer knows his stuff, the DAC will do it when and where it's most relevant. Like just about all DACs already do.

I can feel new 'friends' cursing me even before I post this.

I always thought mp3 and flac files were 'piped' directly into the Dac and came out in analogue. I haven't been interested in DSD as presumed I wouldn't hear a difference like with flac Hi-Res, and also it must shorten battery life with all the added demand on the processor. Maybe I'm missing out.

 

[gregorio]

Threads on new DAP's coming out often mention the way it can upsample, a lot of talk follows about converting PCM to DSD, what is the advantage to simply playing flac or mp3 files?

None at all, it’s all marketing!

In the late 1980’s/early 1990’s DAC chip manufacturers started implementing a new conversion method. Essentially, convert the PCM data by massively upsampling it, reducing the bit depth to just one bit and applying noise-shaped dither. It was cheaper to implement than the older method and provided some minor advantages. In the mid 1990’s Sony came up with the bright idea of essentially taking this 1bit, highly upsampled digital signal, recording it to optical disk using DVD technology (but calling it SACD) and rebranding this process “DSD”. By the time they released it to the public (about 1999) the DAC chip manufacturers had moved on to even higher sample-rates and several bits, overcoming potential issues with 1bit, although the audible benefits were close to zero.

So if audiophiles want to convert PCM using a 30+ year old, obsolete conversion process (DSD), that’s up to them. Personally, I’d rather just let a modern DAC do its thing the better way. Although it’s virtually certain there are no audible differences, unless as castleofargh stated, a designer chooses to deliberately degrade the performance of one or the other.

G

 

[bigshot]

Short answer… it shouldn’t matter.

 

[castleofargh]

OFF topic modo whining:
If you find something on the forum that you think shouldn't be there, please report it instead of creating a trail of quotes of the very thing that shouldn't be there.

 

[Ryokan]

I wouldn't find much (any?) of my music in DSD anyway, it's mostly classical.

reducing the bit depth to just one bit and applying noise-shaped dither.

G

Why would they apply dither?

 

[gregorio]

I wouldn't find much (any?) of my music in DSD anyway

It had two main problems as a format:

Firstly, it couldn’t be mixed/processed/mastered without being converted to PCM anyway.

Secondly, and more applicably to just using it as part of a DAC process, it had a fundamental technical flaw as detailed/proven by Lipshitz and Vanderkooy in their 2001 paper: “Why 1-Bit Sigma-Delta Conversion is Unsuitable for High-Quality Applications”.

G

 

[Ryokan]

It had two main problems as a format:

Firstly, it couldn’t be mixed/processed/mastered without being converted to PCM anyway.

So why not leave it as PCM and let the Dac do the rest? Or is that too easy?

 

[gregorio]

So why not leave it as PCM and let the Dac do the rest? Or is that too easy?

Not as profitable. They could charge a lot more for SACDs than for CDs and despite the DSD DAC process being simpler, they charged a lot more for SACD players! TBH, it was pretty clever: Cheaper to make but charge more for it.

G

 

[redrol]

FLACs for ever and ever. I can just transcode for situations that need a smaller file size and I have the actual PCM data. win.

 

[Davesrose]

I wouldn't find much (any?) of my music in DSD anyway, it's mostly classical.

I collected SACD when it was a thing. I did it because there were classical albums coming out with remastering of old studio masters (like RCA's older classical catalogue). There were some exclusives, and titles the same price as new CDs. Sony did have some SACD players that were inexpensive (seeing as they were pushing the format). One could argue that they didn't make any difference with CD, and the SACD player I have was more expensive/complicated because it's trying to have "quality parts" going out of analog outputs. There were a limited series of rock SACDs, but they had no difference technically from previous CD issues. The only advantage they had for some rock albums was a 5.1 surround track. Honestly, though, for rock I really enjoy blu-ray: you get video and a surround track. One of my treasured SACD titles that's out of print now is Bach toccatas and fugues with 4 organs in a cathedral (which was a remaster from an older quadrophonic album). Sony also employed a copy protection scheme where you couldn't rip audio off the DSD track. Now there are more players that let you get it from HDMI (so if I wanted to back them up). It really doesn't make sense to me to convert something to DSD, or audiophile arguments that DSD or a hi-res PCM is better. Especially since delivery media has been intended as 16bit, and technically that's enough for our hearing (if you pick out differences it's with the mixing/mastering of the song). I do have a portable player that accepts PCM and DSD formats...for a laugh, I could try comparing a SACD rip on DSD or PCM: but it's a lot of effort and if there is a difference it could be up to converter. Maybe there's theoritical degredation at the data level converting back and forth, but then still, does it take many generations to reach the areas that would be audible?

 

[Davesrose]

I always thought mp3 and flac files were 'piped' directly into the Dac and came out in analogue. I haven't been interested in DSD as presumed I wouldn't hear a difference like with flac Hi-Res, and also it must shorten battery life with all the added demand on the processor. Maybe I'm missing out.

Note that a file that's mp3 means it has "lossy" compression and flac is "lossless". They get uncompressed before going to another stage like converting digital data to analog (lossy reducing data information that might not be perceived, while lossless preserves all data). Now that we have larger storage mediums, lossless formats have gotten more popular (and now that we have broadband internet, bandwidth for lossless audio has gotten to be a non-issue). At the very least, you don't have to worry about situations were there might pereptual artifacts from having too much compression: but then also it wasn't hard to find the best quality to size compression settings that's optimal for mp3.

 

[gregorio]

There were some exclusives, and titles the same price as new CDs.

Sure but the majority of SACD releases were more expensive. Plus, if I recall correctly, Sony were due to loose patent/royalties on CDs, while SACD at that time was still a fairly new patent. Exclusive titles were a valid reason to buy SACDs/players, as was the fact that SACD playback could only be achieved on a home Hi-Fi system. Neither of these are applicable to upsampling a recording on playback though.

Sony did have some SACD players that were inexpensive (seeing as they were pushing the format).

I’m not sure how “they were pushing the format”, if anything they were going backwards and even an inexpensive SACD player was still more expensive than an inexpensive CD player. Maybe some deals could be had at the end, when Sony realised SACDs were dead/dying and wanted to get rid of stock. Sony also eventually licensed the player tech to third parties (for a royalty of course) and they could take advantage of the relatively cheap production costs.

One could argue that they didn't make any difference with CD, and the SACD player I have was more expensive/complicated because it's trying to have "quality parts" going out of analog outputs.

Sure but you also had CD players with effectively the same “quality parts” in the analogue outputs.

G

 

[71 dB]

I collected SACD when it was a thing.

Try buying physical copies of the new releases of BIS label without SACD being a "thing." SACD never took off as a mass market audio format nor was it ever indented to be such. SACD was always a niche format. The only question was how popular niche format? Well, it became a niche format with quite limited market with just a few labels still using it meaning on the niche markets it is still a thing even if on the mass market it has been death for a long time and never really was a "thing" to begin with.

Popular things are not automatically "relevant" and vice verse. No matter what your interests (hobbies etc.) are, you are likely to need niche markets, because most people aren't interested of the same things you are. A lot of mass market products and services are stuff to fulfil manufactured needs, things that people believe they need because of effective marketing. A few years ago nobody felt the need to buy a baby Yoda doll. Then Di$ney manufactured the need to buy one. So, baby Yoda became a popular thing, but is it relevant? No. Di$ney could have come up with something else.

 

[71 dB]

I always thought mp3 and flac files were 'piped' directly into the Dac and came out in analogue.

Not sure what you mean by "piping" in this context. Any PCM to analog DAC requires PCM data. Since mp3 and FLAC aren't in that format, they have to be decoded into PCM before "piping" them to a DAC.

 

[71 dB]

I wouldn't find much (any?) of my music in DSD anyway, it's mostly classical.

What keeps you from getting into classical music? Prejudice?

Why would they apply dither?

Because you need to use dither when you reduce bit depth and going from 24 or 16 bit to just 1 bit is a MASSIVE reduction in bit depth! Sure, the increased sample rate helps, but for example with DSD64 only 6 bits worth of truncation is dealt with that way I believe, but the rest of the reduction needs proper dithering.