MartinLogan Grotto [17/24] Grotto advantages

All dynamic drivers generate distortion caused by spider

and surround nonlinearities as well as voice coil inductive

disturbances and variant motor strength during massive

woofer excursions. These challenges plague all subwoofer

designers. The result? Induced harmonic and intermodulated

distortions causing dramatic disturbances at high excursions.

This occurs significantly in almost all non-servo controlled

subwoofers.

To dramatically reduce these phenomena the Grotto utilizes

servo monitoring and control via an advanced circuit that

corrects for any acoustic deviation from the pure audio

signal, resulting in a 3 to 10-fold distortion reduction (depend-

ing on SPL) over traditional dynamic driver technologies.

The Grotto's low-pass filters achieve extremely precise cross-

over points in both amplitude and time domain resulting

in seamless blending with both MartinLogan and non-

MartinLogan products. By tailoring custom filters to the main

speaker roll-off characteristics, minimum group delay results

in cohesive integration and musical results.

25Hz Level Control

The Grotto 25Hz level control allows custom sound tailoring

capabilities found in few subwoofers. A room, especially

when small, can greatly exaggerate bass in the 20–30Hz

range. The Grotto’s 25Hz level control knob increases or

decreases lower bass to compensate for these room anom-

alies. The 25Hz level also allows increased deep bass if you

desire a sub-sonic sense of energy at the lowest frequencies.

GROTTO ADVANTAGES

Grotto Advantages 17

Servo-Controlled Dynamic Driver Low-Pass Filters Maximize Blending