Hi good people of the lower register! I have been reading this forum occasionally through the years and I am almost always finding the answers. In the recent weeks some new depths and questions occurred to me and I would dare to directly ask it here. Recently I have swapped my Peavey Firebass 700 head for a Genz Benz GBE 750. My old cabs (Marschalls MCB110 and MCB115) still remain but that would have to change soon because I do believe that I could draw a finer sound from my amp with some finer cabs. The question 1 is: should I remain at 2 ohms load or should I go to 4 instead? According to the amp specs, it gives 750W @ 2 ohms and 625W @ 4 ohms. The difference in the wattage is not really significant but I am not sure how much does it transfer to the sound in a way of the quality. I do believe that the loudness is here more a subject of the speaker configuration than of 125W difference. Is a long service with 2 Ohms actually damaging to this amp is what concerns me as well. A am a hobby player and i do not change my equipment often. The questions 2 is the optimal configuration of speaker cabs, regardless of impedance. The 410/115 setup was long thought default normal to me, 10's delivering the mids, 15 delivering the lows, tweeter giving the highs... Then I've learned that that is not the loudest setup and scientifically far from the optimal solution. Ii know that it is very much depending on the model and the manufacturer of the cabs but I wonder what would it bring to swap the 115 with some 212 or even 215 and to leave that 410. There are off course the other options of single cabs like 610 or 810 which I never tried. The question 3 is the much asked question of the wattage relation between the load cabs can take and the power that the amp pushes through them. The most common that I cared of is that the power that goes in the cab should not exceed it's constant load limit because of the danger of blowing the speakers. The new thing that I read is that it is not recommended to push less (or a lot less) power in the cab than it can take because one should then crank up the volume and by doing that the amp takes a lot of strain and distorts and in return the speaker/s get square waves which we do not want as well. Those who warn strongly about that suggest using amps that can push more watts through the cabs that they can take, because we never crank them up all the way. That way they maximize the use and loudness of the cabs and in turn they do not push their amps to hard. To me it looks like that seems fitting only for those who really, really know their equipment good, which is now not the case with me. 4 would be only a simple recommendations of cabs. Stuff like Messa or Aguillar are just to expensive for my league. Warwicks, Peavey, some used Ampegs, SWR, maybe EBS, Hartke... Ashdown, GK? I play mostly in a rehearsal room with a somewhat louder band. When we gig, we often take only amp heads with us. We play mostly death metal, not too technical. My play-style is pick (often a lot of fast, interrupted picking), low action, some frat-buzz and stainless steel stings tuned to flat D (A on 5er) My basses are ESP LTD B 2005 with hot EMG's and a Warwick Vampyre SN 5 string with fat MEC's compressed with EBS comp. and dirtied with Boss ODB-3 (that one I intend to swap with some Darkglass drive). The sound that I chase is something like a rolling of metal tracks, rumbling and heavy with distinct metal rattling. Thank you very much for your time!