Looking for Focal Stella amplifier suggestions

My main headphone listening setup uses a 10.5” iPad Pro, running the Onkyo HF app with lossless and often hi-bit files into the Apple USB/Lightning adaptor. From there a Dragonfly Red is run with some old Monster brand ⅛” to RCA jacks and into the Massdrop Alex Cavelli tube hybrid amp (CTH). I am using the Stellias with the Focal 4-pin XLR jacks. 
Prior to the Stellias my main phones were the Shure 846’s. I listened to those for many years prior to the Cavelli purchase and thus was truly blown away by the difference the Cavelli made to the entire soundstage and dynamic range. So, I know that I do like the Cavelli and appreciate the difference it makes to the Shures. 
Having never tried any other amp with the Stellias, and enjoying the Stellias but also finding them to have a very closed soundstage I’d be interested in trying a different amp. Might have considered the Arche but not thrilled that it was discontinued. I’d would love to hear any feedback for choices (particularly if they could be home-tested and returned if necessary). My small town does not have any hi end audio shops anymore and other than Best Buy no other audio options. Thanks for your time!
Stellas fortunately are pretty easy to drive. They will benefit from upgrades of all your equipment for a long time to come. I prefer the natural tube sound and use Woo headphone amplifiers. I can recommend the WA6, WA6se, and definitely the WA5... which is an order of magnitude better than the other two. The headphones will also greatly benefit in upgrading to a high quality streamer and DAC. I am fortunate to have high quality Aurender streamer and Ayre DAC. Each costing many thousands... all the steps getting their are well worth it and complement these excellent headphones
Quicksilver Headphone Amp, but you’d have to work with a dealer (or the company) to see about a home trial.  Best of luck.