Here are some measurements of Monacor Sound-4BT.
It's a powered bookshelf speaker manufactured by Vistron (Dong Guan) Audio Equipment.
A slightly modified version is sold in Sweden, by "Intelligent Sound" (IS Monitor 4e). You've probably never heard of them, but it's a controversial manufacturer, claiming that the only thing that matters in a speaker is the crossover. Thus, they take inexpensive/bad speakers, replace the crossover with a secret one (hidden in epoxy glue) and sell them at 5x the price (or more).
Anyway, the speaker tested here is the original version. I measured the passive/right speaker, connected to the powered one.
My measurements are quasi-anechoic, with near-field port+woofer, combined and corrected for baffle edge diffraction, merged with gated outdoor measurements at 1m distance (5ms window).
A massive port/cabinet resonance and uneven woofer response. The tweeter peak at 9 kHz can also be seen in the 1m measurements (resonance or breakup).
Horizontal directivity:
0-90 deg for comparison with Stereophile measurements:
Vertical directivity:
Distortion:
I don't know why, but distortion at ~500 Hz - 4 kHz is lower at 90 dB SPL, while bass distortion is much higher (as expected). I measured three times (and the results above are with another power amplifier), but it made no difference. The mic was not clipping.
Here's a zoomed out view. 200% distortion at 50Hz.
I have attached a recording of the bass distortion. It's a combination of port noise and woofer distortion. The volume was low, and the woofer wasn't bottoming out.
It wasn't bottoming out during the distortion measurement either, but the port made a lot of noise.
The speaker isn't broken, and it hasn't been abused. It was just as bad when it was new.
My thoughts:
It's a powered bookshelf speaker manufactured by Vistron (Dong Guan) Audio Equipment.
A slightly modified version is sold in Sweden, by "Intelligent Sound" (IS Monitor 4e). You've probably never heard of them, but it's a controversial manufacturer, claiming that the only thing that matters in a speaker is the crossover. Thus, they take inexpensive/bad speakers, replace the crossover with a secret one (hidden in epoxy glue) and sell them at 5x the price (or more).
Anyway, the speaker tested here is the original version. I measured the passive/right speaker, connected to the powered one.
My measurements are quasi-anechoic, with near-field port+woofer, combined and corrected for baffle edge diffraction, merged with gated outdoor measurements at 1m distance (5ms window).
A massive port/cabinet resonance and uneven woofer response. The tweeter peak at 9 kHz can also be seen in the 1m measurements (resonance or breakup).
Horizontal directivity:
0-90 deg for comparison with Stereophile measurements:
Vertical directivity:
Distortion:
I don't know why, but distortion at ~500 Hz - 4 kHz is lower at 90 dB SPL, while bass distortion is much higher (as expected). I measured three times (and the results above are with another power amplifier), but it made no difference. The mic was not clipping.
Here's a zoomed out view. 200% distortion at 50Hz.
I have attached a recording of the bass distortion. It's a combination of port noise and woofer distortion. The volume was low, and the woofer wasn't bottoming out.
It wasn't bottoming out during the distortion measurement either, but the port made a lot of noise.
The speaker isn't broken, and it hasn't been abused. It was just as bad when it was new.
My thoughts:
