I've been using tubes for years and was beginning to think about solid state to rid me of tube nuisances and expenses now that I am retired. I am listening for hours each day and replacing tubes is just too expensive. I also thought my KEF Reference 3 speakers might benefit in the bass region from solid state. Pass Labs I believe would be a great compromise, tube sound, solid state reliability. My budget is the only constraint but for now I am exploring but not sure if I need to be class A or AB. In class A, new I am thinking of the XA30.8 and in class AB it would be the X100.8, however used I could move up one notch in power but it would be the .5 editions. I would love to be class A since from my research they seem to have the greatest tube sound, but would the XA30.8 be too low powered for my KEFs? Currently my tube mono blocks are 38 watts per channel and it seems plenty of power, my room is 13 ft wide by 15 ft deep. I tried a solid state 400 watt per channel amp and the bass was more detailed but wasn't sure if this was just a result of the amps being 3x more expensive and therefore of a higher quality being able to bring out more detail. Both the borrowed SS amp and my tube amps went equally deep just more detail and a bit sharper edged with the SS amp. Any suggestions / thoughts on power requirements and class in the Pass Labs line that would match with my KEF speakers would be appreciated. I use a Backert Labs Rhumba 1.2 preamplifier if that helps.