So I have a pair of NHT ST4s, used for 2 channel music only. Looking to upgrade them. Right now I'm powering them with a NAD T955. I have them bi amped. I wondering if a pair of NHT T5 towers would be a good upgrade ($700) or NHT C4 towers ($1,200). My budget is probably $1,500 max. Or is their something else I should be looking into?\nRT-85 turntable\nMarantz 1609 for pre amp\nNAD T955 power amp\nRoom is about 13 feet wide and 43 feet long.