need a little help. amp problem?

[51st8]

hello

i have a question and i wonder if anyone could help me.

is there any different between 4 and 8 ohms amps?

I own b&w 685 speakers and yamaha rxv 365 which has 4 ohms.
when i was in a shop in a show room they have had b&w 685 connected do the MARANTZ PM6003 AMPLIFIER which has got i believe 8 ohms. in the show room i was really impressed about quality and power from such small speakers.
i cannot get it form my yamaha rxv 365 which has got about 105 watt per channel.
so... does it matter if there is 4 or 8 ohms?

and last question:
i did buy harman kardon avr 355 and i wonder if its going to be good enough for my speakers for now? is it any good choice?
in the future gonna change it for rotel and cm7 or 9... but its just a plan.

many thanks for your advise
chris

[rickp15]

Most, if not all recievers over 100$ will do 4 and 8 ohm speakers.

[Ralph]

Not sure about your speakers but my B&W's do not fall less that 6 ohms. Just make sure that your amp will handle a 4 ohm load with out getting to hot. Some amps almost double the watts on lower ohms fust fine.