BAT Vk-51 SE vs Aesthetix Calypso

I had the 51SE then downsized somewhat and had the Calypso, everthing else in the system was the same at the time.

I thougth the Calypso was a very nice preamp but not in the same league as the BAT. The BAT was quieter and had more of the dynamics and heft you mentioned. To me it just sounded more natural.

I don't think the comparision is fair to the Calypso as the retail price of the BAT was twice the cost. I think here you get into that area of diminishing returns. To me the BAT wasn't "twice" as nice as the Calypso but in my system and in my opinion it was a much better preamp.

You may want to seek the signature version of the Calypso.

BillandSol:
I forgot to mention that all of my listening with the 51SE was with 6H30-DR supertube. That was the standard tube in the preamp at that time.. As you probably know those are more scarce now.

I don't know much about the Calypso but I own a BAT VK50SE and later a VK51SE for 9 years. IMHO, the BAT sounds closer to a solid state than to a tube. Please beware of that when you make decision.