• TomJ
  • ADAT user
  • Offline
  • Registered: 2019-10-01
  • Posts: 15

Topic: ADI-2 DAC XLR output stage - discrete? class A?

Is the XLR output stage of the ADI-2 discrete or op amp?  Does it operate in class A?  Thank you.

2 Reply by joachim.herbert (edited by joachim.herbert 2019-10-01 13:12:31)

  • Registered: 2018-06-29
  • Posts: 89

Re: ADI-2 DAC XLR output stage - discrete? class A?

Does it matter, and why so? Thank you.

  • TomJ
  • ADAT user
  • Offline
  • Registered: 2019-10-01
  • Posts: 15

Re: ADI-2 DAC XLR output stage - discrete? class A?

The question pertains to the quality of the analog output on the XLR terminals.  I've seen contradictory claims about this online but no mention of it in the user manual or product specs. When an output stage is biased to operate in class A and/or implemented in discrete components, that's usually something that the vendor does report. - cheers, Tom

4 Reply by Curt962 (edited by Curt962 2019-10-01 17:05:56)

  • Registered: 2019-01-07
  • Posts: 1,462

Re: ADI-2 DAC XLR output stage - discrete? class A?

Tom,

Perhaps you could share an Overview outlining the advantages of a discrete Amplifier Stage?    Hmmmm. 

Curt

Vintage 2018 ADI-2 DAC. "Classic AKM4490 Edition"
Cables:  Red, and White Ones.
Speakers:  Yes
  • TomJ
  • ADAT user
  • Offline
  • Registered: 2019-10-01
  • Posts: 15

Re: ADI-2 DAC XLR output stage - discrete? class A?

I suggest you ask that of vendors who do so.  I'm simply trying to resolve conflicting claims that I see online about the ADI-2 DAC.

  • KSTR
  • AES/EBU artist
  • Offline
  • Registered: 2019-02-25
  • Posts: 106

Re: ADI-2 DAC XLR output stage - discrete? class A?

The output is comprised of OPA1602 opamps. Those have a quiescent current of 2.6mA, so their output stage runs at 0.5mA or thereabouts (educated guess here). This means the output stage is operating in class A for up to about 5V peak into a 10k load. Thus, in a normal consumer connection scenario (<=2Vrms levels required, >=10kOhm input input impedance), the output will remain class A at all times.

  • TomJ
  • ADAT user
  • Offline
  • Registered: 2019-10-01
  • Posts: 15

Re: ADI-2 DAC XLR output stage - discrete? class A?

thanks great, thanks KSTR!