last night I was listening to my new M60's and I took the speaker grills off while i was listening to them and they sounded so much crisper and cleaner. Am i hearing things in my older age, or do these speakers sound better without the speaker grills on them?

I don't think there is any evidence they sound better without the grills. I've done tons of listening with and without and couldn't tell a difference. Having said all that, I still left the grills off in the off chance that there a subtle change. Your mind can play havoc with your happiness.

I'd say if you don't have kids, leave the grills off and enjoy what you hear.

I take the grills off when i really sit down to do some listening. I think they sound better with them off. A little crisper like you say. And my non scientific way of telling myself that it would affect the sound is try blowing through the grill cloth. It doesnt go through like it would without the grill cloth.

That being said, I keep the grills on most of the time now days. I was the exact opposite a couple years ago but i have become attached to the sleek, slim look they have with the grills on. who knew.

Mojo has mentioned the M80s sound less sibilant(was that it Tex?) when the grilles are on. I haven't put the grilles on mine yet, still enjoying the look of all those drivers so I really can't comment. I have noticed that the grille cloth is now thicker than in the past. When the grilles are on my M22s/VP100 I can still see the drivers through it, but on the newer M80s/VP150 when the grilles were on, ever so briefly when they first arrived, I couldn't see the drivers.

When I had Mojo toe-in, my ears objected to naked M80s. The highs were too sparkly. I haven't tried listening for a difference with my current, zero toe-in configuration. I know what Ian and Alan said about the grill being practically transparent at all audible frequencies and I have no explanation for what I heard. I suppose someday I should convince myself by taking SPL measurements with varying frequency. I only tried this once by the way so it's not a statistically significant result. I do remember however that I was listening to a native flute close to what I believe was its top end.

That's interesting about the grille cloth thickness. We should compare our grills, Jason. I'm only speculating but maybe Axiom is trying to respond to reports of brightness.

They're like sunglasses for speakers.

Oddly enough this is one thing i have not done A/B blind yet though i'm inclined to side with Alan's comments on the non-effect of the speaker cloth.
Sound is not exactly like hard wind rushing at your face. It is air related and pressure related but the speaker cloth, being as light as it is, should have a negligible effect on the sound pressure created by the drivers within the room.
That being said, i did see some heavier plastic grills with rather narrow holes on some Energy speakers. Now THAT would impede air flow immediately off the driver cone more significantly.

In subjective tests i cannot say i recall any big or noticeable difference between having the grilles on or off my Axioms. Being such a potentially subtle effect if any, i think only an A/B test could help to define it.

The blow test isn't very good for testing a grill cloth for acoustic transparency since your mouth is a poor model for a speaker driver. Now, if you can move your tongue forward and backward at 200Hz and greater, I stand corrected (and she's a very lucky girl).

I just measured at 10KHz. It's louder by 1dB...with the grills ON ! I measured three times with the same results.

My explanation is that the cloth acts as a lens.

Ok you guys. Go measure before you go to bed tonight. How can you possibly sleep without confirming it yourselves?

I also figure that because the grill frames stick out past the baffle you wouldnt get as good of soundstaging. Or something. All i know is that a set of sansui speakers in the garage that have literally a 1 inch lip around the entire front for the grille to fit into seems to really make them sound... Bad. i think is the word im looking for.

Or severely chafed.

But with music being waves of sound and you put something in front of it such as the grill cloth is it not going to change the
or manipulate the direction in which the waves are moving thus making the speaker sound slightly different?Just a thought.

I like to share major problem I found my m80 grills. Grills are starts to rattling from the middle to the top after 6 months old. I remembered removing the grills about 5 times since I have them. It very flimsy made. Soft and very flexible.
I notice the rattling noise when I watch Transformer movie at the beginning scene when the chopter frying over the desert. Another movie is the Master of the Commander by Russell Crow. The cannons going off during the last scene of the movie. I now have double side M3 tapped from middle of the grills to the top across the grills.