SAM and its troubles

[beerman]

Hi,

Kef LS50 were one of the first speakers got SAMed by Devialet, and whoever heard the combination knows why Devialet had chosen to do this.
Actually, the LS50 benefits from SAM: I noticed expanded bass, wider soundstage and transparency. Improved Dynamics. If you have a suitable room, this could be the end of a journey.
Unfortunately I have some room modes, when I play the Kefs solo.
So I configured a high-pass at 70 hz, 2.Order for the Kefs (unfortunately you can't do that with SAM) and configured the Devialet's mono subwoofer output full frequency range into the DSpeaker Antimode 8033IIs for room correction and then to my Linn Melodic subwoofer with a intern lowpass of 79 hz.
I chose this configuration because of measurements and listening tests.
This relieves the Kefs from the deeper bass frequencies, what has a very good effect on music reproduction. I think this is a result of the smaller movements of the LS50's loudspeaker diaphragm.


Kef LS50 with SAM


Kef LS50 with dap-corrected subwoofer (no SAM)

The measurements are with 1/24 Octave resolution.

Beerman: that's an interesting comparative graph even though they cannot be directly compared. First, they confirm that SAM is (of course) not about room correction (this idea pops up now and then) but impulse correction. Otherwise it should have eliminated the room modes at 40, 65, and 100Hz. The room correction that you use to tame your modes, however, acts on the non-SAMed speakers.

Do you think you could provide a measurement using SAM and the DRC simultaneously?

By the way, what measurements were these: Which microphone, which program, which distance or location of the microphone relative to the speakers?

Hi Mohmm,

I made the measurements with the Analyzer App for iPad. The Mic was a calibrated MicW i436. The measure point was where my head was in listening position. The distance to the speakers was ca. 3 meters.

Here is a measurement with active SAM plus dsp-corrected subwoofer: