Axiom Home Page Forums General Discussion Technical Questions Question about comparing two speakers

I am a newbie, non-audiophile comparing speakers and have a couple of questions I was curious about.
I have a pair of axiom M22 I was comparing with CSW M80 speakers. I have one pair on the "A" speaker connections and the other on the "B" with the receiver set to Stereo. When I switch from one to the other, the CSW are noticably louder, confirmed via an SPL meter, roughly 2 db. What technically accounts for that? Is that a measure of "sensitivity"? Looking at the specs, the Axiom is rated at 93 db with the CSW at 86 db. I don't quite know if "louder" is "better" though. The axiom do seem "clearer".
Next question, I was playing the Who's Next CD. A couple of the songs had introductions where a single instrument was playing (guitar, organ, etc,). I noticed the sound seem to originate from the opposite side as I switched speakers. E.g with the Axioms the guitar sound would appear to be coming from the left speaker, then after switching to the CSW, the sound appeared from the right side. Then when another instrument or vocal came in, they also appeared to be imaged a little differently. What accounts for that? the speakers were about equal distant apart and i was in the middle between them (like a triangle).
I anyone has any other tips on what I should look for when comparing speakers, I'd appreciate it.
thanks

Hi emiburke,

Welcome to the Axiom boards. There are various ways to measure and state speaker sensitivity. Sensitivity has nothing to do with sound accuracy, fidelity or overall quality.
The most common standard is to measure the speaker's output sound pressure level (SPL) in an anechoic chamber at 1 meter with 1 watt of input power, using a contoured noise signal. That's called anechoic sensitivity, and for the M22ti, it is 89 dB SPL. Axiom also quotes room sensitivity (93 dB for the M22ti), which indicates the speaker's acoustic output in a typical room, where room surfaces reinforce and increase the speaker's output. (An anechoic chamber has huge absorbent baffles to absorb all reflections and echoes, hence "anechoic").

I don't know how B&W arrived at their sensitivity measurement. In any case, other things being equal, if the B&W is louder, then it has greater sensitivity and their rating is too low.

If you are comparing speakers, you should make sure that the volume (SPL) measurements are identical when you switch. In double-blind listening tests in which I participated for many years at the National Research Council in Canada, even a tiny difference in volume when comparing speakers causes listeners to often choose the louder speaker as sounding "better," so it's essential to equalize volume levels to get meaningful results.

It's no surprise that the Axiom M22ti sounds clearer than the B&W. B&Ws tend to be somewhat muddy and rolled-off in the midrange. While some B&Ws can be quite pleasant, they tend to be a line that's quite inconsistent from one model to the next, the latter likely a result of lack of scientific controls and double-blind procedures in their listening comparisons.

Are you sure you don't have the channels reversed in your hookup of the Axioms and the B&W? That would explain the switch to opposite sides when you switch.

The two speakers will certainly image differently because I suspect the B&W is very non-linear through the midrange, which would create quite different imaging. You should also try comparing the two speakers in mono (just one speaker of each) to isolate tonal differences very precisely. Comparing two different speakers in mono is a very rigorous test.

Regards,

one thing i have noticed is that regardless of what the sensitivity rating is for a speaker, what makes to seem a speaker loud or not is its bass. If the other speaker you tested has more pronounced bass, it may seem louder.

All you really have to do though is turn of the volume or adjust the bass managment and it should be fine.

thanks for the replies

Doh! yes, I had the cables mixed up on the B side.

The other speakers are Cambridge Soundworks, not B&W.

They are a 3-way with an 8-inch woofer, so yes they do have more low end. I tried to compensate for this by putting them on the B side, which doesn't use the subwoofer on my receiver. Then the Axiom M22 was on the A side, using the subwoofer (I have a pretty basic onkyo 150 watt sub). Crossover is set at 80hz. In this configuration the Cambridge still are louder and "fuller", about a click or two on the volume different. so, maybe it's the two larger woofers making the difference.