In case anyone is still interested, I finally got my stuff back from my tech yesterday and AB’ed the 2150 & Langner Brutus. Will play them more later. It’s basically what I expected. The Langner is louder (it’s four 6550’s mono), bigger, more powerful sounding, more organic, 3D, warm, just a more beautiful, rich tone to my ears, but it’s also looser and less precise & pristine sounding. It overdrives quicker on the volume. Like I said before, it kinda sounds like how I’d imagine it being if you took just the power section of my ‘89 SLO, made it beefier and replaced its 5881’s with the 6550’s it’s got in there. The 2150 sounds more clean, pristine, precise, much tighter, more modern, more extended lows I think, but less low mids. The 2150 comes off more transparent to what you put in it, but the color the Brutus has is a beautiful color imo. The 2150 is flatter in eq curve, while the Langner has some nice mid and uppermids going on like an SLO. Both keepers, but the Langner is more inspiring overall for me. Now I gotta eventually re-visit and try the mono 400 watt input of the strategy 400 to see if it can redeem itself from the boat anchor status it had next to my iic+ and iii++ coli’s lol