Oversampling: Who Does It Best?

[57gold]

After reading this and only getting that two respected, experienced, technical guys can have such varied opinions on software and hardware...I can only conclude that:

 

a) these are developing technologies; and

 

b) I do not even belong in the "drawer" and should find better things to do than read stuff like this, like play guitar, listen to tunes, focus on making $s...yikes!

[Alessandro Dalto]

On 1/19/2011 at 5:58 PM, Charles Hansen said:

The Cirrus Logic CS4398 has a switched-capacitor analog stage, which in conjunction with an internal op-amp provides a voltage output. I have never been a fan of op-amps...

Hi, is the opamp you are talking about inside the Cirrus Logic 4398 chip (before the differential analog output), or outside to the chip? 

Anyone can answer this for sure? thank you very much

https://statics.cirrus.com/pubs/proBulletin/CS4398_Product_Bulletin.pdf

https://statics.cirrus.com/pubs/proDatasheet/CS4398_DS568F3.pdf

[The Computer Audiophile]

5 minutes ago, Alessandro Dalto said:

Hi, is the opamp you are talking about inside the Cirrus Logic 4398 chip (before the differential analog output), or outside to the chip? 

Anyone can answer this for sure? thank you very much

https://statics.cirrus.com/pubs/proBulletin/CS4398_Product_Bulletin.pdf

https://statics.cirrus.com/pubs/proDatasheet/CS4398_DS568F3.pdf

Perhaps @Ryan Berry could help answer this one as Charles, the person you quoted, has passed away. 
 

I know this isn’t an Ayre specific question, but figured Ryan may know. 

[The Computer Audiophile]

I can also reach out to Cirrus. I have a good contact there. 

[R1200CL]

Without reading tread, I taught external SW was the preferred solution these days, and that HQPLAYER does it best. Which may limit the DAC’s to select among. 

[One and a half]

5 hours ago, R1200CL said:

Without reading tread, I taught external SW was the preferred solution these days, and that HQPLAYER does it best. Which may limit the DAC’s to select among. 

If software players would drive a hardware device like a series of gates at the DAC end, then yes software would be the better choice on a *very* simple DAC with no filtering.

 

Problem is, DACs have to cater for a signal that it knows about, USB, TOS, S/PDIF and the more software manipulation there is, has a negative impact on what comes from the DAC. It's like fighting two different filtering systems and ending up in the middle, which is fruitless. Then repeat the exercise for different music!

I2S was a start, there's no standard, and it's LVDS anyway. HQPlayer or roon can upsample, tried both and the latter is particularly odd and un-natural. The former has so many filters, too much time is wasted in figuring out the correct filter that works with your DAC's filter.

 

Some Dacs sound good at redbook, others really suck at it, some work best on DSD and the signal source of USB, TOS and S/PDIF are used as a transport as a baseline and the filtering and DA conversion whether with FPGA or a ladder resistor array is up to the designer's choice.

No way to make a blanket choice on software and how DACs behave.

 

BTW,

I've seen many a post from you in threads, the 'h' is missing from the word, a tread is something you step on as part of a stair construction, or the pattern in car tyres.

[Alessandro Dalto]

12 hours ago, The Computer Audiophile said:

I can also reach out to Cirrus. I have a good contact there. 

I wrote you in private Chris.

[The Computer Audiophile]

3 hours ago, Alessandro Dalto said:

I wrote you in private Chris.

Got it. Email sent to Cirrus. 

[Ryan Berry]

On 11/25/2021 at 8:33 PM, The Computer Audiophile said:

Perhaps @Ryan Berry could help answer this one as Charles, the person you quoted, has passed away. 
 

I know this isn’t an Ayre specific question, but figured Ryan may know. 

 

We do know.  It looks like the question may be answered?  If not, send me a message.

[The Computer Audiophile]

Here is what I just received from Cirrus:

 

"The CS4398 is a voltage output DAC (as opposed to current-steering) and we recommend an external filter circuit which includes an op-amp (Figure 11 in the CS4398 datasheet available here on cirrus.com https://statics.cirrus.com/pubs/proDatasheet/CS4398_DS568F3.pdf)."

[Alessandro Dalto]

5 hours ago, The Computer Audiophile said:

Here is what I just received from Cirrus:

 

"The CS4398 is a voltage output DAC (as opposed to current-steering) and we recommend an external filter circuit which includes an op-amp (Figure 11 in the CS4398 datasheet available here on cirrus.com https://statics.cirrus.com/pubs/proDatasheet/CS4398_DS568F3.pdf)."

This doesn't answer to my question...

How is possible that the cs4398 chip has an output of 2.3 vdc?

Is there an op-amp inside the chip that gains voltage right before the differential output?

[Miska]

I still have a tube almost full of CS4398 chip. In ~2010 I made an ADC/DAC that I call DCA1 that uses PCM4202 for ADC in DSD128 mode. And CS4398 DAC also in direct DSD128 mode. CS4398 is one of those DACs that have Direct DSD mode bypassing all DSP.

 

Another DAC I have with this chip is Marantz HD-DAC1.

 

On 11/30/2021 at 11:11 PM, Alessandro Dalto said:

Is there an op-amp inside the chip that gains voltage right before the differential output?

 

Yes, there is, as typical for switched capacitor filter DACs (Crystal/Cirrus and AKM).

 

 

 

[Alessandro Dalto]

On 12/3/2021 at 5:18 AM, Miska said:

I still have a tube almost full of CS4398 chip. In ~2010 I made an ADC/DAC that I call DCA1 that uses PCM4202 for ADC in DSD128 mode. And CS4398 DAC also in direct DSD128 mode. CS4398 is one of those DACs that have Direct DSD mode bypassing all DSP.

 

Another DAC I have with this chip is Marantz HD-DAC1.

 

 

Yes, there is, as typical for switched capacitor filter DACs (Crystal/Cirrus and AKM).

 

 

 

Sorry I've been busy.

Thanks for answer, so it's as I suspected.
The weird thing though is, why is there no mention of any op-amp in their scheme like the one you attached here?

[Miska]

On 1/23/2022 at 4:43 AM, Alessandro Dalto said:

Sorry I've been busy.

Thanks for answer, so it's as I suspected.
The weird thing though is, why is there no mention of any op-amp in their scheme like the one you attached here?

 

Is it somehow relevant? SCF conversion DACs are typically voltage output ones.