Garylim you will hear many things from audiophiles about the 801s. Some are true some are not. I would listen to actual owners and ask about their setups.
One thing true IMO is that this 801 is not a plug and play speaker. This means you will need experience and time. The first will come with the latter but patience is needed. Many audiophiles lack patience if I look at my friends. With me its not that I have a alot of patience but I am more stubborn.
For this reason alone I would skip on them unless you have patience - it could become a slippery road.
I have no experience with the Yamahas.
I have known around 12 - 801 owners personally. Half from this group made the speaker their last, some with modifications. The other half moved on. Of the remaining ones many are now running a tube pre and amp/s. This was all that was needed for a few of them to eliminate the ESL speaker setup in the other room.
You will not get what this speaker has to offer unless it is mated to a high current ss amp.
Zenblaster what amps have your tried other than a 4b?
The 4bs had one good trait with me. Control of the woofer.
But they lost it on the mid/tweeter. And I am a Canadian that does not want to bad mouth another Canadian company.
Based on my experiences I would rephrase your statement to say "quality power" amp instead of high current SS amp. It covers more bases IMO. I know some that listen at low db with their 801's. This is possible with a tube amp too.
So 801s need quality power whether SS or tube. The better the power quality gets - the better they keep sounding. I have not hit their limits yet in my room.
Based on my experience they sound really good on a quality 75-100 watt tube amp that is capable at 4 ohms.
I have owned my current S3 since 94-95 and 801fs prior to that.
A good reference site I can recommend.John Bowers BAF
It will make you understand how the 800 matrix series were designed by John Bowers to be run in a sixth-order Butterworth alignment.
Some owners have chosen other BAF's. Krell, Northcreek, custom. I am considering the third option as a final step for me.
I have also provided a number of observations on my 801 ownership on my virtual page if you do choose them.
Look for Winnie the Pooh.
Cheers and Good luck.
A big Hello to other 801 owners here. I think its time we were more vocal guys. Someone start an 801 owners thread I would participate ? I have yet to find a speaker that brings this kind of energy into my room that wont cost me a second mortgage.