I believe the 800 has two 15’ (I am verifying that) My 500 has two 10’s and a 15. Both rigs were ran at about half with overall volume controlled on the bass.
So, have you tried your Rumble 500 at a bit more than half? And/or duplicating the 800's EQ settings, as best you can, on the 500? Half of the 500 is not the same as half the 800. Of course, the Bassman has some EQ advantages over the Rumble besides wattage, like the
Deep switch, sweepable mids, tube preamp.
I do believe both amps are class D but the 800 is a seemly heaver more solid amp.
Yep, both Class D ICEpower amps. How about the 800's cabs? Are they Bassman neos, or what? The Bassman 115 neos are power rated a bit higher than the Rumble 115s, but not a huge amount. The Bassman wood is slightly thicker, but I don't believe the electronics are much, if any, more 'solid'. The 800 head weighs less than 20 lb.s compared to almost 50 for the 100, and 65 for the Super (300)!
There is no doubt the rumbler series is built to be lighter and I would suppect that would cause a lighter feel in the “thump” but that is just my guess.
Both the Rumble and Bassman are built to be light in
weight, but that doesn't necessarily translate to light in sound. I can get very similar, very heavy, very thumpy feels out of both my Rumble 500 combo and my Bassman 500 w/115 Bassman neo cab. It's all in the EQ-age, then adjust volume as needed. If you're running your Rumble at just half, you've still got plenty headroom to play with.
I sure dont want a second amp that dont have the big “feel”.
The 500 has served but the “balls” of the 800 were bigger.......
Try all kinds of EQing first. If you truly can
not get there any kinda way, then get the 800 and another 115 and see if that gives it to you.