Welcome, San! That "old" V2* Rumble 350 (
manual here) is only 8 to10 years old, being first introduced in 2011. The new V3* Rumble 500 (
manual here) was introduced in 2014, when I got mine, which has been just terrific ever since.
They are
similar in that they output up to 350 watts continuous by themselves into 2x10" special design speakers with a Class D power amp. They both have built-in, pushbutton, footswitchable Overdrive with
similar controls. They also both have Bass controls at +/-15dB @ 80Hz and Treble at +/-15dB @ 10kHz. The 350 has a Scoop pushbutton "shape" filter that is
similar, but not identical, to the 500's Contour filter.
They are
different in that the 500 can also run an extension cab for up to 150 watts more power, while the 350 can't. The 350 has Fender speakers while the 500 has Eminence speakers. The 350 has a semi-parametric midrange with Level & Frequency controls, while the 500 has fixed frequency Lo-Mid & Hi-Mid controls. The 350's Gain control only affects the Overdrive, while the 500's Gain adjusts your bass' incoming signal level in addition to interacting with the Vintage pushbutton "shape" filter and, of course, the Overdrive. The 350's Punch filter and the 500's Bright filter are each unique to themselves. They are also built of different woods giving very different weights (obviously), which probably affects tone, even though both are quite expertly tuned.
They can
probably be made to sound very much alike but, they certainly
have ways to sound very different from each other! It's interesting to note, however, that the Rumble bass modeling amps have different digital models for the V2* and V3* non-modeling Rumble amps!
TLDR: So, the short answer to your question is "yes" and "no".
*Version2 Rumbles produced 2010 - 2013, Version3 Rumbles produced 2014 - current
.
