acoustat 2 speakers for around 500 are a steal if they are in good condition..the 2+2 and 1+1 models are very good, too, but stand 8' tall
your amplification is adequate at best is my guess. I can a pair of Acoustat 2 speakers with a modified Hafler DH200 (110 watts) years back; did not work very well. In fact, a Bedini 25/25 played louder and with better bass than the Hafler..go figure.
I would want something more along the lines of the Levinson ML9 (25wpc@8ohms, 400 watts @ 0.5 ohms) or a more recent Krell/Threshold/Levinson/Plinius type of amplifier with a monstrous power supply. Or a really powerful valve amplifier like one of the older VTL pure triode monoblocks.