ESS Sabre Reference DAC (8-channel)

Re: Re: LME49713 and LM7171 for I/V converter and AD797 non buffered output

promixe said:


If you look here - http://esstech.com/PDF/Application_Note_Component_Selection_and_PCB_Layout.pdf at the table on page 2, you can see that LME497xx family actually had inferior DNR measurements in comparison to AD797. The data is for 9008S but I'm sure it is as relevant for 9018S.


The 49713 is a current feedback opamp. Very different then the 49710/20/40, which are voltage feedback.
 
Has anyone measured DNR/THD of OPA627 in real world scenario with either the ESS Eval board or Buffalo?

Nagaesan was kind to offer his subjective listening test results, but I am specifically interested in direct comparison between OPA627 and AD797 (not only subjective listening tests, but actual performance figures). OPA627 is available in TO99 package, while AD797 is only DIP/SOIC. AD797 is also about half the price of OPA627.

Is there a real objective reason I would want to pay double for OPA627 in terms of performance/flexibility/etc?
 
AD825 OPA627 AD797 LME49713

I think we should better I/V converter OP-AMP of ES9018, AD797 to AD825.
We Japanese tryed AD797 to OPA627, but AD825 is better.
Please see also this page. The photo that I/V stage, you can see.
http://www.teddigital.com/ESS_Es9008s_en.htm
AD825 is much more smoother than AD797.

But I misunderstood why ES9008S sounds "Harshness Femail Vocal and Violin", I was thinking speed and settling time before hearing 9018, but it was digital filtering output bit rounding matter.
ES9018 eva-board had AD797, but sounds very smooth.
This 60bit accumlator and ditherd rounding 32bit digital filter is superior one.

But I recomend, we should better replace I/V OP-AMP much more faster and short settling one, like AD825.
AD797 CMRR is good than AD825/opa627, so I think AD797 is better than others unbalance differential OP-AMP.

And I think SOIC is good for high impedance circuit like I/V stage.
The guard pattern that DAC-IC current output pin to I/V input pin create very easy.

**** Note! **** Do not use LMA49713!!!
 
Infomation of 32bit DAC audition party

Hello every one.

Next Friday night and Saturday afternoon, I hold DAC audition party. At this event, of course ES9008S and I/V OP-AMP modyfied version is introduced.

Possibly I may introduce the sound of new 32bit DAC evaluation board from TI/BB.
And now I asked DENON DCD-SX to lend this weekend.
DENON DCD-SX is adopted AsahiKasei 32bit DAC AK4399.

So I would like to borrow ES9018 from Japanese ESS inporter ArrowUEC, but there are some reason, it seems to be difficult.


If someone ESS people watch this page, would you ask this to ArrowUEC people?
 
Re: Infomation of 32bit DAC audition party

nagaesan said:
Hello every one.

Next Friday night and Saturday afternoon, I hold DAC audition party. At this event, of course ES9008S and I/V OP-AMP modyfied version is introduced.

If someone ESS people watch this page, would you ask this to ArrowUEC people?


Please see this page
http://www.ikeon.co.jp/communication.htm
 
Re: Infomation of 32bit DAC audition party

nagaesan said:
Hello every one.

And now I asked DENON DCD-SX to lend this weekend.
DENON DCD-SX is adopted AsahiKasei 32bit DAC AK4399.

Now I had a infomation that AsahiKasei AK4399 exhibition was decided.
 

Attachments

  • dcd_sx.jpg
    dcd_sx.jpg
    12.1 KB · Views: 1,733
OpAmp measurements

promixe,

Douglas Self has posted measurements of a few popular opamps on

http://www.dself.dsl.pipex.com/ampins/webbop/opamp.htm

They include the 797 and 627

Cheers

Ian







promixe said:
Has anyone measured DNR/THD of OPA627 in real world scenario with either the ESS Eval board or Buffalo?

Nagaesan was kind to offer his subjective listening test results, but I am specifically interested in direct comparison between OPA627 and AD797 (not only subjective listening tests, but actual performance figures). OPA627 is available in TO99 package, while AD797 is only DIP/SOIC. AD797 is also about half the price of OPA627.

Is there a real objective reason I would want to pay double for OPA627 in terms of performance/flexibility/etc?