Actually the DP-X1 uses two DACs in single ended mode with the Active Ground Control the DACs run in serial when dispensing a single-ended signal. I think people have mentioned it in the thread.
The schema was in the initial post :
Just to add to what
davidmolliere and others have posted, and my findings on a huge amount of research regarding the Onkyo DP-X1 from varying sources including Head-Fi (I'm on page 72 of this thread, will eventually, and soon, read everything), here is how I think you can use the DP-X1 in all it's configurations:
- SE only (single DAC, single amp),
- SE with AGC (dual DAC's running in serial*, single amp),
- Balanced (dual DAC's, dual amp's),
- Balanced with AGC (dual DAC's in serial**, dual amp's),
- Use DP-X1 as a balanced DAC only. Here the DP-X1 balanced DAC's are in action but you bypass dual DP-X1 amp's via 2.5 mm TRRS, then use an use an external balanced amp such as ALO CDM (via 2.5 mm TRRS input) or balanced desktop amp (with correct cables and adapters),
- OTG/Use DP-X1 as a source only (fully bypass DP-X1 circuitry and use external DAC/amp, such as the Chord Mojo/Hugo/Hugo TT, CEntrance HiFi-M8, ALO Continental Dual Mono, etc).
- (Speakers on DP-X1?).
*One DAC runs ground, and sends signal to second DAC according to this video of an Onkyo representative in John Darkø's article (cannot embed Vimeo video hear, sorry).
**Same idea as above but this time each of the DP-X1 amp's will separately go to left and right signal via balanced 2.5 mm TRRS output.
Just to touch up, as an Onkyo representative, various articles and Head'Fiers have posted, AGC should work in SE mode.
The whole AGC idea is incredibly unique. If I am right on all of the above the amount of experimentation will be insane. I'm going to elaborate on the AGC bullet points here:
What I find interesting is that if you wish to use AGC in SE, one of the ESS Sabre ES9018K2M DAC's is set to ground, and the other converts the digital signal to analogue for both left/right channels. Only one of the two ESS SABRE9601K amp's is used for both left/right channels as well.
If true then supposedly we should have a greater noise reduction. That's great for SE users but we only get to use one of the two DP-X1 amps.
The real cool thing is if you want to use AGC in balanced mode you can, same AGC DAC topology as above, but each DP-X1 ESS SABRE9601K amp is dedicated to left and right signals respectively.
My high interest in this is; is balanced only king (one DAC and one amp/channel), or is AGC in balanced mode better? Or both unique that both are king?
To me AGC in balanced is the best of two worlds, one being high-end, well implemented SE but with better grounding, and the other being dedicated left and right channel amps. No idea if that translates into great SQ.
I can only test SE and AGC SE when I get my unit (I have no balanced headphones as of yet) but those who have their own units and balanced headphones, if you have the time please experiment and post your findings. Thanks!
EDIT:
As per
nanaholic personal experience with his Onkyo DP-X1, Japanese translations and official documentation, it seems the English sources may have been incorrect; AGC in SE most likley is not sonically viable or redundant. Please read further posts from this point on.
