Jadis Preamps JPS8, JPS2 and JP80

Loki1957 mentions the two volume controls are tied together (ganged).
Does anybody know (as I've seen some preamps) with this feature and some products without.
Is this is something they did a newer production models or older models or  models for a few years and now the newer ones are no longer tied together?
I've seen them ganged in jp80mc from the 90's.  

Resurrecting this thread, and thanks for your answer rcprince.
My system (at the moment) is a Levinson 519 file player/DAC driving Mcintosh MC601 mono into B&W 802D3.

it sounds quite good, but I also own a Jadis JPS2, actually the fully balanced version JPS2S.

Since the Jadis has no remote control and has dual volume controls (not ganged), I have some level control choices.

I can put the 519 on fixed output (which is essentially full volume), and use Jadis volume and have (maybe) best sound but lose remote control of volume-

OR

Leave Jadis volume controls where they may sound best (maybe about halfway open?), and use remote and phone app to raise and lower volume on the 519?

Suggestions/comments of any kind related to this system? Is there anything incompatible about using Jadis preamp with Mac solid state MC601 amps?
A short while back a gentleman who already owned some Jadis amps commented that he thought the Jadis preamp was only properly usable with Jadis amps (maybe he was referring impedance matching).
im hoping to hear from maybe Almarg or atmosphere, and all opinions are welcome.
thanks