[bigshot]

Many modern DACs (based on AKM, Cirrus Logic chips) do support the NOS Mode (via NOS filter emulation).

I don’t know why inferior performance should be looked at as a feature, but that’s the audiophile world for you. Most DACs and players have perfect sound to human ears right out of the box. You have to really go out of your way and spend a lot of money and set it to bizarre settings to find one that doesn’t.

 

[gregorio]

Hmm.... if you were not surprised, then I am surprised why you stated the above. Did I (or you) miss anything?

Apparently you are missing a great deal!

If you don't mind, could you please let me know what results you are referring to? Thanks.

The ones posted on your blog and just reposted here, the images showing the results/output of a topping DAC when using the filter option which emulates a filterless NOS DAC.

G

 

[sunjam]

Apparently whatever the settings are, the way they are it is not working according to the requirements of digital audio to function correct, otherwise you would see perfect sine waves on the output. I don't know what that chip or that DAC is doing exacly but I can think of some possibilities.

It is simple,

1. send a perfect 10kHz digital sine wave (44.1k Hz, 16 bit format) to a Topping E30
2. select filter F5 (Super Slow Roll-off, aka "NOS mode" filter) on Topping E30
3. check the analog output on an oscilloscope

 

[sunjam]

Apparently you are missing a great deal!

The ones posted on your blog and just reposted here, the images showing the results/output of a topping DAC when using the filter option which emulates filterless NOS DAC.

G

which emulates filterless NOS DAC with analog filter

Just wondering are you surprised finally?

 

[bigshot]

It emulates a dog’s breakfast.

 

[theveterans]

I don’t know why inferior performance should be looked at as a feature, but that’s the audiophile world for you. Most DACs and players have perfect sound to human ears right out of the box. You have to really go out of your way and spend a lot of money to find one that doesn’t.

I have a hunch that these started with goldensound apparently passing blind ABX on two different DAC filters, and OP probably concludes that NOS sound different (to subjectivists) and thus negating that DACs that measure 0.0000x% THD+N sound the same

 

[bigshot]

It’s assuming that different is better I guess.

 

[gregorio]

It is simple,
1. send a perfect 10kHz digital sine wave (44.1k Hz, 16 bit format) to a Topping E30
2. select filter F5 (Super Slow Roll-off) on Topping E30
3. check the analog output on an oscilloscope

Exactly, you select the F5 filter option, which emulates a filterless NOS DAC!

which emulates filterless NOS DAC with analog filter

No, it emulates a filterless NOS DAC only, a non-oversampling DAC with a functioning reconstruction filter will NOT produce that output! This is what you seem to be missing!

G

 

[bigshot]

I guess he figures a filter is a filter.

 

[sunjam]

Exactly, you select the F5 filter option, which emulates a filterless NOS DAC!

No, it emulates a filterless NOS DAC only, a non-oversampling DAC with a functioning reconstruction filter will NOT produce that output! This is what you seem to be missing!

G

So, you believe analog filter would only be applied for all the filter settings but not for F5?

 

[gregorio]

Just wondering are you surprised finally?

Yes, extremely surprised that you claimed a “good learning technique” and repeated the importance of “critical thinking” but have actually demonstrated no critical thinking and an exceedingly poor learning technique!

So, you believe analog filter would only be applied for all the filter settings but not for F5?

No, I believe the actual facts, that it’s possible to design a digital filter that modifies the signal so the output of it’s analogue reconstruction filter emulates the output from a NOS DAC without a filter! Please follow your own claims and apply a “good learning technique” and critical thinking!!

G

 

[theveterans]

It’s assuming that different is better I guess.

Even among subjectivists, it's divided to two camps: those who are in the ultra-steep brickwall filter (Chord WTA million tap sinc filter) and those who are "NOS purists"

 

[sunjam]

Yes, extremely surprised that you claimed a “good learning technique” and repeated the importance of “critical thinking” but have actually demonstrated no critical thinking and an exceedingly poor learning technique!

No, I believe that actual facts, that it’s possible to design a digital filter that modifies the signal so the output of the analogue reconstruction filter emulates the output from a NOS DAC without a filter! Please follow your own claims and apply a “good learning technique” and critical thinking!!

G

Got it. You mean F5 does have analogue filter then. Thank you.

 

[gregorio]

Got it. You mean F5 does have analogue filter then. Thank you.

I don’t know for sure as I don’t precisely know the design, it is theoretically possible that the output from the F5 filter bypasses the oversampling and reconstruction filter but I would be very surprised. It would be far easier/cheaper to simply design the F5 filter so the output after the reconstruction filter is the same as the output from a filterless NOS DAC.

G

 

[castleofargh]

Got it. You mean F5 does have analogue filter then. Thank you.

It's a messed up filter, there are no staircases with the other filters, which is evidence that this filter in particular is the problem(and not CD or whatever narrative your blog tries to sell).
The original article spends a lot of time on that filter and showing how it's a weird filter that does not attenuate out of band frequencies nearly enough. It's because of how little the filter removes above sample rate/2 that we get to see the staircases we should only see without a filter(which is also showed on the other staircases screenshot from, this time, a DAC with no filter).
For straight lines like a momentary DC signal, you need infinite bandwidth. A properly band limited signal does not have that. No matter how you spin that example, the result will remain the same. A correctly filtered signal would never look like that.

It's funny how out of 6 filters, you only looked at the clearly defective "let's recreate vintage crap" one, and invented some story about hires out of it. IDK if it's an attempt to generate traffic or your idea of a fun April fools experiment where you try to propagate the old staircase story to see how gullible people are?