Good to know that Zenfone sounded good. More option to choose from other than Xperia when the time comes for my V60. Price for Xperia is quite expensive and my experience with Xperia 10 II isn't that good (my wife's phone) as there's this frequent rebooting of phone which will soon descends to bootloop (happened twice so far) which was only recoverable by using Xperia tools which means that it reset and clean everything on the phone. It still have the frequent self-reboot issue even after. And there're many reports of green/pink lines appearing on Xperia 5ii.So after reading that thread and being aware that asus changed their dacs to a qualcomm built in dacs i bought myself a new Zenphone 9, being fully aware that it might have its dac badly done.
Well the answer - it is done perfectly.
So there's small review.
Actively used amps\dacs
1) Abigail and Charmtek trp24
2) Sonata E44
3) Steinberg UR22mkII with balanced connection to Ifi Zen Can
Actively used iems
1) Moondrop Chu
2) Salnotes Zero
3) Shouer S12
4) Sony IER-M9
So small preable. I wanted some new phone with actual good jack output, seeing the comments here and seeing that asus rog phone 6 switched to qualcomm dac there was concerns over how Asus implement that dac. I am fully aware that my actively used IEMs are quite efficient so i am fully aware that this dac probably wont drive something overly juicy. But the combination of small size (I LOVE SMALL PHONES), big battery (oh it is BIIIG) and jack sold be on buying that phone.
Frequency response: One of the reason i actively use cx31993 dongles and Sonata e44 is that they have same FR as my desktop Steinberg + IFI Zen Can. And Zenphone 9 deliveres same FR. Dead same.
Soundstage and imaging: After testing it with E44 and Abigail i found out that Zenphone has the same soundstage width as E44, and same somewhat cramped depth as E44 (compared to Zen Can). It was quite clear that Abigail was more dense and blurry in that regard.
Dynamics: That's where Zenphone did a sliiight step back compared to E44. Sometimes in some track it was audible for a moments that decays were bit off compared to E44 (I was testing it with balanced cable and 4.4mm to 3.5mm adapter). Granted that cases were REALLY rare. And you need to actively search out for them. Meanwhile compared to Abigail it was quite clean on testing that more cramped soundstage in Abigail hid some dynamics problems as well.
Power: Never did more than 50% on volume with POWERSAVE AUDIO OUTPUT ON (ye, it seem that they did full power implementation of dac with ability to make it low power in power management setting).
Conclusions: I'd say if the phone had same output as cx31993 dongle i would be pleased, but the phone actually overdelivered. The implementation of that DAC is quite great.
Master audio is crap as all DSPs yeh, but overall "hack" is to put it on music mode and it will skip all DSP.
I am really happy that i dont need to carry on dongles anymore to get great sound. Thanks Asus for a phone with actually good 3.5 jack. And actual day lasting battery (easily does 10hours of seeding wifi, playing youtube with screen on and playing music through iems).
I know that i might be insufficient for headphones or iems that requires power just to drive them but given my iems i'd say that "scalability" of power is not an issue here for more or less efficient ones.
If V60 is still viable at that time I might still go with V60.