will my old marantz sr18 hard to push the b&w 684's?

my dad just gave me his old ATI four channel amp. Will this solve the problem? I heard the b&w speakers are harder to push at the same volume. ( will this increase my basee performance once I hook it up with the amp? )

Actually the 684s have a sensitivity of 90dB and are rated at a nominal 8 ohms with a range of 25W to 150W recommended amplifier power. So no, they are not difficult to drive. You get down around 85dB with a 4 ohm rated loudspeaker and yes, they need a lot more power. I believe the B&W line of speakers are relatively easy to drive with lower power if that's what you have. But you would probably get more out of them at higher driven amps. Much also has to do with the quality of the amplifier over just pure watts from mass maket receivers and amps. Just my opinion.

Yeah I would think that the SR-18 would be more than adequate to power the 684's. Unless you've got these things in a huge room i think any improvement with using the ATI amp will be negligible.

is about 50 clean watts if i remember. this is the one with the oscilloscope, right? if it was made in japan, its better, the usa made one was slightly less good.

anyway, that 50wpc is likely fin unless youre going to play VERY loud.