Why some preamps weigh 50+ lbs?


I’m looking at an integrated but am open. I just was looking around and there are preamps weighing 50-70 lbs! Why ? What could be in a damn preamp that would weigh 50+ lbs. ? 

mofojo

While not exactly 50 to 70 lbs, my purist preamps, yamaha C5000 (~42 lbs) & luxman c900u (~43 lbs) are not exactly lightweight gnat farts either...

I am increasingly convinced that the yamaha is the best sounding out there, not to mention it is a work of art.

I have also seen some cost no object eurocrap that is just foolery when you actually open it up...the weight alone doesn't mean much.