i did phazon core w/o using hbj and im sure that its possible to get the plasma with using solr frenzy method, i have a video but no description so its hard to do..
recit-wasnt solar frenzy just the effect of unmorphing after a bombjump. if so then yeah you need it but it needs to be after an hbj in order to get the plasma beam. solar frenzy alone will not do the trick. also how did you manage phazon core without SJ. i hope you werent thinking phazon processing cause i know you dont need hbj for that. phazon core is the big room just before metroid prime