speaker doesnt seems to follow technical specs

[mARCELOCM]

Hi, i have a setup using a Loxjie a30 + Cambridge Audio SX-50 and i took a measurement from 1m apart from the speaker and looks like this:

is it normal to look like there is no bass at all? if a change the tone settings in Loxjie it doesnt appear to change anything, to my ears it has a minimum more bass but little more distortion too.

sx-50 specs:

SENSITIVITY	87dB
FREQUENCY RESPONSE	50Hz-22kHz
IMPEDANCE	8 Ohms compatible
RECOMMENDED AMPLIFIER POWER	10-100 watts
DRIVERS	5.25” (135mm) treated paper cone woofer 1” (25mm) Silk dome tweeter
CROSSOVER	2 way
PORTED	1 rear
MAGNETIC SHIELDING	No
COLOUR	Black or walnut
DIMENSIONS (HXWXD)	225 x 161 x 240mm (8.9 x 6.3 x 9.4")
WEIGHT	3.0kg (6.6lbs)

 

[voodooless]

Looks like your window size is too small.

 

[mARCELOCM]

Looks like your window size is too small.

sorry, i dont understand, my window?

i see that the speakers maximum output is at 200hz, but its supposed to be high until 63hz, in the case it roll off too much below 200hz

 

[voodooless]

sorry, i dont understand, my window?

Window function - Wikipedia

en.m.wikipedia.org

There should be a setting for this in your software. If not, try increase the FFT size (2048 in your example) by several orders of magnitude.

 

[Sokel]

Doesn't seem strange considering the specs of your speakers and the usable 18 watts @8 Ohm of your amp.

 

[sam_adams]

sorry, i dont understand, my window?

Choosing the wrong FFT length reduces frequency resolution. Choosing the wrong window type increases aliasing in the frequency domain—amongst many other effects.

Spectral Audio Signal Processing - Julius O. Smith

Spectrum Analysis Windows (same author different format)

Understanding FFTs and Windowing (white paper download on page)

Choose The Right FFT Window Function When Evaluating Precision ADCs

Window Functions in Spectrum Analyzers

 

[mARCELOCM]

Seems like its the higher window solved, the new measurement: