Axiom Home Page Forums General Discussion Technical Questions Maximum usable dB for each speaker model?

I was wondering, more out of ignorance, the following:

When the manufacturer states, for a given speaker, 150W max amp power and a frequency range of 60Hz to 22kHz, given a "pure" unequalized signal, that the speaker will perform distortion free (or even port noise free) at that wattage or does that mean the max wattage before the speaker will start experiencing some sort of permanent damage?

The reason I ask is that I suspect, for a dedicated and modestly sized Media Room that "contains all the sound energy", I will not need large speakers like someone with a listening area open to other rooms. I have already been down that road with HUGE speakers for exceptional sound. In the past it has typically been the bigger the speaker (in a given line) the better the sound quality. Current market demands for small speakers have seemingly pushed manufacturers to offer the same quality in a smaller speaker but with less output (be it sound or low frequency...there always has to be a trade-off).

I know it is possible to order Axiom speakers and if you are not happy to return them and upgrade but my wife has little tolerance for that and expects me to get it right the first time.

I have been considering the M2i but even Doug Schneider had it crossed over at 100Hz, seemingly to prevent port noise (he did not say at what level he was listening). I'd prefer 80Hz.

I have decided to mount speakers on wall brackets below the screen to 1)avoid being too close to the side walls to prevent/reduce boundary effect, 2)allow for better speaker positioning and 3)not to compromise the integrity of my vapour barrier by using inwalls.

M2i speakers would work best size-wise as I would like to avoid m22ti speakers mounted in a horizontal arrangement. If all else fails I may have to use M22ti speakers mounted lower vertically and try to keep the tweeter as close as possible to ear level.

I will also be using the identical speaker for all three fronts to get the "best" sound (thanks to Axiom for the Factory Outlet where I can have the option of ordering a single speaker).

Anyone?

Bruce, at least in theory, the published maximum power spec is supposed to be power that could be input continuously without the speaker being permanently damaged. It doesn't directly relate to any considerations of distortion or port noise. All speakers have considerable(compared to electronics)distortion at far less than that maximum power number, which is unlikely to be used in typical home listening, since it would be equivalent to about 109dB for 150 watts at the listening position, considering the 87dB sensitivity rating of the M2.

I didn't note that Schneider gave a crossover number in his review of the M2, although he did comment that the usable bass was to about 70Hz. A 80Hz crossover for the M2s should work well, judging from the NRC graph. The M22 did show lower distortion at high levels in the NRC tests and might be preferred for that and its slightly higher sensitivity. My M22s worked just fine right on the floor and tilted slightly backwards(the tweeters don't necessarily have to be at ear level if they point to ear level)when I experimented with them when they first arrived. I would think that you could do the same if you had about 20" of room below the screen and wouldn't even have to bother with wall brackets.

You can order single speakers through the main page and not just the factory outlet, unless there's some secret rule I don't know about. Right under the picture on the product page it has 'add pair' and 'add single' options. Just a heads up if you don't want to wait for the factory outlet.

And Bruce... if you and the missus want to give a listen, let me know... I can at least give you an audition of M3s... which, with their lower stretch into the bass, might be an option.

Seriously, no trouble at all.

Bren R.

Brens' suggestion of at least looking at the M3s is a good one.

I ran three M3s across the front with great success until we moved into a larger place and I had to go to floorstanders for mains.

Still running the single M3 as center though!!

I cross my M3s at 60, so 80 is absolutely no problem!


Note: I also like to run M3s as surrounds as well as center, all inverted for tweeter location.

I also like mustard and wasabe on waffles; so.....

Thanks Bren. I will definitely take you up on that offer at some point. It is probably better that my wife sees and hears speakers closer to the size I am actually going to purchase (unless of course I end up purchasing the M3s as they are close to the same size and price).

I figure the wall brackets will save the speakers from the vacuum.

Bren, did you audition the M2s or just went straight for the M3s?

In case it helps, here are my notes from comparing M2 with M3. This was more in the context of standalone use w/o sub but there may be some useful points. For what it's worth, if I was putting together a system for a medium sized room and was concerned about SPL I would happily go with M3s over M2s. For a small room where I know the M2s would be loud enough I would probably stay with M2s since the mid-bass is a bit flatter. The "M3s are more laid-back" point is true but more subtle than you might expect.

http://www.axiomaudio.com/boards/showflat.php?Cat=&Board=ST&Number=86248&page=&view=&sb=&o=&vc=1

>>I have decided to mount speakers on wall brackets below the screen to 1)avoid being too close to the side walls to prevent/reduce boundary effect, 2)allow for better speaker positioning and 3)not to compromise the integrity of my vapour barrier by using inwalls.

One concern with this approach is that the sound is not going to appear to come from the screen, ie voices won't appear to come from people's mouths. I find this disconcerting although not everyone does.

Best approach seems to be to have mains and center "averaging" to the centerline of the screen, eg if your center is above the screen then have the mains below the centerline so with a typical mix the sound will seem to come from near the center of the screen. Just a thought...

I would dearly love to see the sensitivity and power handling numbers combined into a single "this is how loud they will comfortably play" ranking but you would need to be a lot more nitpicky with the power handling -- today it is never totally clear whether the number is "this is the amount of power required to play average content at the loudest level this speaker is happy with", or "this is a good size of amplifier to match with this speaker", or "above this power level you're gonna be melting voice coils, buddy !!"

I'll second the M3's.I also run them as surrounds mounted on my back wall about 7ft high with fmb's.Sometimes I play them and my M60's in 4 speaker direct or just turn off the 60's and kick back and enjoy the M3's.Love them so much I am going to get a second pair for another room

I definitely like the sound of the M3, even though I am using them as centers. I may have to get another set for the computer room to run as mains.

In reply to:

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Bren, did you audition the M2s or just went straight for the M3s?

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I've heard the whole line of bookshelves now. And exactly as you think they'll sound... they sound... the M3s with the bigger woofer extend a bit deeper and stand alone without a sub fairly well (in fact if not for the S.O. I'd probably be happy enough without a sub)... the M22s (even as an M3 owner) are clearer (more detailed as the audio fan vocab nazis would say) but I'd say a bit thinner... one of those cusp things... the M22s are more accurate, absolutely... but the M3s sound fuller to me. Having said that, I've had the M3s since we moved in, and I listened to the M22s for a grand total of 2 movies I think. While I technically haven't heard M2s, the M22s with the bottom driver taken out of circuit's a close approximation. Not perfect, since the enclosure's the wrong size, then... and I really wasn't too impressed... don't get me wrong, they're better than Paradigm Mini Monitors to my ears, and I'd use a pair for a living area stereo or my office or something, but I much prefer the M3s.

And I just took a flyer, guessed at what I'd be happy with, and think I nailed it... eventually I will probably move to M60s just because in hindsight, I don't really like the look of bookshelves on stands, not due to performance issues.

And seriously, the door's open anytime you want.

Bren R.