Bookshelf Speakers

Axiom M3 v3 Bookshelf Speakers


On the Bench

Measurements were taken from 1 foot away at a height equal to the center of the driver or at the midpoint of the drivers for full range tests with the speaker at least 4 feet away from the nearest wall.

THD+N measured 0.67% at 1 kHz and the 3rd harmonic was the largest at 46 dB below the primary. There were some interesting residual harmonics at 2.5 kHz and 3.5 kHz, but the loudest was still 75 dB below the primary.

THD+N measured 0.68% at 10 kHz and the first harmonic (albeit inaudible to anyone over the age of 1 month), was 45dB below the primary.

Going to the speaker's low end we usually measure @ 50Hz but I got a max of 97.6dB at 50Hz before I hit 10% THD+N. Since 50Hz is below the speaker's published +/- 3db frequency response lower range of 60Hz, I retested at 60Hz where I managed 100dB with 5.8% THD+N. Not bad for a bookshelf! The fact that the M# uses a fairly "large" 6.5" driver here really helps, you'll definitely hear the bass full range or to be blown out of your seat you will need a sub.

Just for fun (okay I forgot to move the mic) you can see the in-room response at 2m vs. the response from 1ft away in the graph above. Some of the same characteristics show up at 2m as they do at 1ft but you can see (yet again - if you needed further convincing that is) that your room can be as much a factor in how your speakers sound as the speakers themselves. I got some nice in room peaks at 50 Hz and 100 Hz with a corresponding valley @ 75 Hz in the 2m test that were not present in the 1ft. An 80 Hz crossover to the subwoofer would be fine for these speakers which is great for bookshelf speakers. Often in this size speaker you can end of crossing over at 120 Hz or even higher and the directionality of your subwoofer bass is getting compromised at that point.