More power for moderate listening levels?

86 db sensitivity 25 wpc amp? LOL Do you have a buddy with Parasound, A21,23.  Something like that. Krell 100 or 250 wpc, Mark L will push those puppies.. If you want a pitch black background, some type of class d. They are 1/3 the cost of the Pass but 25 X the power.

Not only will they power your speakers, you can see for yourself, without all the bluster about less efficient speakers. BLA BLA BLA...

NOT twice as much 25 times as much..... BUY a bigger amp..

25 watts per channel is 25 watts per channel

If you you want to one up that, Treat as much of the room as you can stand.  I like as little room treatment as possible.

Those are great sounding speakers, with accurate factory measurements.  86 is just fine with todays amps that are from 2-2000 watts, EASY 2-3-4000 WPC not uncommon. No need to scrimp..

So were are clear, I own Pass, First Watt, and two kits I built... and at least 3 pairs of speakers that are 84%.. They can sound up
50 X 50 X 15 dance floor to over 100 db... CLEARLY... Zero floor noise zip nada..... That's with an old vinyl rig too (Russco) and a C20 Mac.

25 wpc? At least it's a good 25 watts... NOW 250 or better...

Regards

Hello,
I agree with so many of you it is hard to keep track. I have had the exact same issues all corrected by the things said in this thread. 200 watt class A to crank up the volume. A used pass 250, you are talking some serious money. I have tried the Ayre, Mark Levenson, Hegel. It’s not the amp it’s the speakers. You can pull 45,000 pounds of freight with a semi-tractor/trailer but only go about 75 Mph or pull practically nothing in a Porsche and go 200 mph plus. To get something to cover it all it’s tough and very expensive. That’s why Porsche doesn’t make semi trucks and Mack doesn’t make sports cars. 
 It’s very simple. For the dance parties get a different pair of speakers like very efficient Klipsch RP-600m maybe with a separate amp. You need a very efficient speaker with a horn or horns in it. Maybe upgrade to the Cornwall. A lot of people put them on the wall so they can be out of the way or maybe on a completely different wall. I say leave your nice sounding system alone and create a second system. You might be able to get away with a BlueNode Powernode 2i $899 with the Klipsch RP-600m on sale now for $450. All the home theater guys love Klipsch speakers and ported SVS subs for home theater because they play loud very well. Everyone who watches a movie in my theater says it’s the best sounding home theater they have been in. That’s because my system is setup for quality not quantity. It will play loud enough for it to be a little uncomfortable which I don’t do.  This can be a rabbit hole you don’t get out of and can be very expensive. Better to avoid the rabbit hole all together. Concert speakers are not audiofile speakers. They consist of an array of horns with humongous bass drivers. If you need the bass to go with your face party add an inexpensive ported sub. 

In my opinion the most overlooked spec when choosing an amp is the reserve amps or instantaneous amps. This is a power reserve that helps especially in the midrange and lower end. It will also improve dynamics and overall sound at all levels. This is a simplified explanation but I don't want to right a whole book here.

Here's the thing.. That  Mack and that Porsche both have close to the same horsepower, and torque.. Look them up you'll see. 2-500 hp with
1-2000 foot lbs of torque..  The difference is the size of the parts..... 
Foot lb of torque... BIGGER

Same thing with speakers, it's where the speaker starts to distort not how efficient it is. The E factor is rather arbitrary, IF the distortion is LOW and reproduction is correct, Audiofile or not.... That is my end of the line goal.

If I can reproduce quality sound from 40db to 115db, I'm a pretty happy soul.  I don't use my ears either.  I've found if you don't run sound test, and collect your own data, your wasting your time..

When I mentioned the 84% speakers, the factory was 89 or 91.. THEY aren't usually accurate, and it's REAL easy to fudge the measurements.

Bigger amp, treat the room... You want to make sure to run some test and see if its running out of gas, and distorting... Pass is not the end all amp it's made out to be.. It is a great amp though.. I like Ampzilla, Serious amp, there. Hook a single 2000, up.. You'll see.. Compare the two..
Wish I would have never sold them...:-( You could have turn them up until your ears bleed, with those speakers... 25 watts is 25 watts plane and simple.

Regards

Brian, I think you answered your own question. If you are straining at times you either need more power, more efficient speakers or add subwoofers and a 2 way crossover. 
I am of the camp that there is no such thing as too much power. XA100.8s would be the minimum IMHO. For that money I would get JC1+'s. Good high powered amps have an effortlessness missing in smaller amps(unless you have very efficient speakers.) Before you notice the harshness the amp is already clipping on transients "stressing the sound."  I tend to go for speakers on the less efficient side, 89dB or so and would never consider an amp less than 200 watts. I also have a tendency to gravitate towards class A amplifiers and I also use subwoofers crossed at 125dB which increases the headroom of my system 10 dB. With all this I can get 110 dB out of ESLs. More than enough to give you a headache. 
With your system I would (and this is me) get a Trinnov Amethyst preamp, XA 100.8's and at least two passive subs. With the Harbeths this would give you a SOTA point source system for sure which should do an easy 105 dB probably more. It would be totally effortless at lower levels and for sure put a big smile on your face whenever you light it up.

Mike