Susvara pre-amp and amp combination

Hello all:
I have a pair of Susvara's and am thinking about pre-amp/amp combo for this. I currently have the KECES E40 which has a sound I like. The rest of my equipment:
Denafrips Terminator II
Denafrips Hermes DDC
Magna mano Ultra MK II
i2s hdmi for all interdigital connections


Not a lot to go on here.  What’s your budget, and are you buying new or used?  What kind of improvements are you looking for vs. the Keces, and what sound characteristics are most important to you in headphone listening?

I am looking for excellent soundstaging, and a bit more definition than the E40.  Used is OK  I have found that I like a good bass without harsh high end. I realize that there are ongoing discussions of amplifiers for the Susvara but never any discussion of pre-amp. The Terminator has no pre-amp functions.

For my own Susvara use, I use an MSB Analog DAC which has a volume control, and an Eddie Current Studio B headphone amp, which also has a volume control but no remote, which the MSB does have. With the right tubes, Susvara sounds awesome through the EC.... 

Budget is the main question. HiFiman makes an amp specific for Susvara the EF 1000. This month they are releasing a version of that amp with a Dac built in.

Taking 15K range. If that's out of range The Bakoon(company has a new name that escapes me) but is greta at half the price also

Has anyone heard the Susvara with Enleum?  Thought I remember hearing about a UTube video that was out but now I can’t find it.

@marco1 - I have, and I think they sound great. I ended up selling the Enleum because I prefer the sound of my tube amps, but if you're good with SS, definitely worth checking out... 

@marco1 - Yes indeed, I have both an Eddie Current Studio B and a Donald North Audio Stratus. I've got WE 300B tubes - these are new ones from their plant in Georgia (state, not country), and they were worth the $1200 they cost. They made it sound like a higher model in the Eddie Current line, if there was such a thing. When I was using JJ and Gold Lion 300B's, I couldn't use the Susvaras and have them sound very good; with the WE's, the Susvara's sound great - not the greatest bass possible, but with the right source, bones are rattled. The experience is like really high end speakers with super mids and trebles and lower mids and upper bass, but could use a sub.... 

Wow, EC and DNA.  You got some serious amps AND tubes going on there.  I think  I’d be very happy with just one.  But the electric blue doesn’t due it for me :-)