The Denon AVR S760h A/V receiver does not come with any Pre-outs, for connecting self-power (studio monitors) speakers.
Any chance you could list the country your in?
So your iPad Pro has a USB-C port, which your going to use for the DAC?
Do you have a budget?
How about the ($250) Topping DX5 DAC/amp?
https://drop.com/buy/topping-dx5-dac-amp?defaultSelectionIds=984613
If you plug a 600-Ohm headphone into a headphone amplifier jack, that only has a 1-Ohm output impedance, there is no negative effect.
If you plug a 600-Ohm headphone into a headphone jack with a 60-Ohm output impedance, it should sound the same as a headphone jack with 1-Ohm output impedance (in...
Try installing the free program Foobar2000, with WASAPI installed, try playing a FLAC music audio file.
Also Foobar2000 has a Graphics Equalizer add-on.