Getting as close to an upright sound was something I was after too. Having bought a Rob Allen Mouse that seemed to do the trick the next thing was to find the right amp. Having gone through a few acoustic amps I ended up with an AER Basic Performer, (in fact here is mine after trading) having seen lots of upright players using AER amps live. It has four 8” cones. It was a lovely sound but still lacking something. Finally I ended up with an FRFR powered speaker and the HX Stomp, it’s the 12” speaker, that’s what I was missing, just the deeper, richer tones of the bigger speaker and then the massive versatility of the Stomp allows me endless tweaks to my core ‘upright’ tone. I have different (albeit small and subtle differences) tones for each Fretless song of our set. I don’t know if it really gives what other would consider even close to a ‘real’ upright tone but flirting around the edges of that idea with the Stomp and the QSC has been immensely satisfying and also enriched our songs no end.