I'm using a Metronic extender with 3 outputs to drive my Toppings (E50 dac and pre90).
Not sure it's available outside of France but similar devices should work too.
https://www.amazon.fr/gp/product/B003K17194
I just set the outputs just under the IR receivers of each device.
Well, it's not working like that...
You can have independent volume level on each input, which should be enough in my opinion...
On top of that, there is a "safe volume mode", to set the highest volume level when you switch to any input.
You can use a mode "Vol memory IN" where each input will set (and remember) a different volume level
(But not sure what you mean by "main volume control")
Extract from the user manual here https://www.tpdz.net/newsinfo/457846.html
I agree with you, most "lo-fi" records could benefit from better sound (or not if it reveals how poor they are)
But sometimes, it's just the right sound for the right aestetic...
Hear the roars from outer darkspace !
I'm sorry to ask, I hope it won't hurt your feelings, but why getting the Sparkos edition if the expensive Sparkos opamps are bypassed ?
For the Sparkos regulators ? (And are they in use when the buffer is bypassed?)