well, Infinity speakers like power... and I KNOW that 3de isnt putting out very much of it... the 7894's built in amp is a tank... the best deck amplifier ive ever seen or heard... I wouldnt starve the speakers for very long (if at all), i'd say get the new deck first... you'll be able to play your music at a louder volume, with less distortion and more overall clarity and punch. Plus I remember you saying something about the 3de not playing recorded CD's well... so I definatly say go for the deck...