Actually, I think there is one two channel dac per channel, used in some kind of complimentary mode. Each channel has its own two channel dac. Don't know if thats always better, or just there for hype.
The RX Z9 has a ton of dac chips for all the channels.
-----Nope sorry I have the schematics right in front of me. :b
I'm a hard core follower of all Yamaha A/V Receivers for years and years.
In your particular case, the RX-Z9 has 6 Stereo DACS for 11 channels total.
...Meaning one DAC only per channel, except for the Center channel as I mentioned before.
100% certain! ...I can even see them from the printed digital circuit board.
{Six stereo DACs mean twelve mono DACs. ...For eleven channels in the Z9.}
What the Z9 has in big numbers though are the DSP chips; eight of them total!
Those are all 32-bit floating point designs. That is a lot of processing power!
...Four are for the Cinema DSP and Hi-Fi DSP, and the other four for YPAO (Parametric Acoustic Optimizer).
Like I said, I got the very detailed graphs plus precise pictures right in front of me as I type these words.
They are part of my extensive audio library.
Denon flagship A/V receivers used differential mode in its DACs configuration, not Yamaha.
Yamaha is putting his main energy on its own made DSP chips.
I'm big on Yamaha, Denon (Marantz), Onkyo (Integra), Pioneer Elite, Rotel, NAD, Arcam, Anthem, Emotiva, Sherwood Newcastle, ... A/V receivers, integrated amplifiers, and separate amplifiers.
* Best is four DACS per channel (Quad Differential Balanced mode). And only the best; dCS home made DACs, EMM DACs, ESS Sabre32 DACs, BB PCM-1704K (K for highest grade), BB PCM or DSD-1792 DACs, and RING DACs (Arcam and few others).
Sooory for the small 'interlude'.
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It's too bad because I have a thread on A/V receivers, but no 'customers'. :b
WBF's members are into separates big time!
Very very very few have a top gun receiver as their main Cinema attraction.
A surround processor (Pre-pro) is the way to go around here.
...With separate power amplification.