Chris - A-Gd R28 amazing with the Quads ? I'm looking at it as a big step up from A-gd R11...Recent new fanboy of A-gd - maaaan their design skills are top notch....love their volume pots as well,...smooth as butter turning them...haha.
It couldn't be better, for me.
I love the synergy of the R2R and the pure and massive power of the amp.
The Quads scales very well with, so all headphones in my arsenal do.
One curiousity is the volume control of the R28.
Keep in mind that the volume characteristic of my R28 is a "100 step super exponential" one, which differs from younger build dates.
I mostly listen at level 65, which means it's 8% of power output. ^^
On younger R28s, Level 65 is dedicated to 60% power output.
It could be a bit confusing to some.
Don't know why Kingwa has changed the volume characteristic.
My guess is, to align with the competitors.
The R28 used as a preamp is also stunning and plays pretty well with my Elac Air-X 407.
Don't need much more for my personnel music pleasure, . . . . right now. ^^
Despite the massive size, it's a no-brainer if you're looking for a powerful AIO R2R.
Btw.
Beware of the clicking sound when turning the volume pot.
It's a discrete ladder one based on resistors for each step to be truly balanced.