MartinLogan Motion 20i vs. Monoprice Monolith THX-265B

MartinLogan Motion 20i Tower Speaker Monoprice Monolith THX-265B Bookshelf Speakers
$2000 $800
Dimensions (H × W × D)
36.60” × 6.80” × 11.70”
930mm × 173mm × 297mm
15.40” × 9.70” × 11.40”
391mm × 246mm × 290mm
Power Type
Passive Passive
Frequency Response
46-25,000 Hz 65-24,000 Hz

Key Takeaways

TLDR Summary: In the arena of high-fidelity audio, the MartinLogan Motion 20i stands as an elegant tower speaker, boasting the brand's acclaimed Folded Motion tweeter for crisp highs and a dynamic duo of aluminum cone woofers for articulate bass. It offers room-filling sound with a sleek footprint. In contrast, the Monoprice Monolith THX-265B, a compact bookshelf unit with THX certification, promises cinematic sound with a controlled directivity waveguide for detailed treble, and a robust driver for potent midrange and lows. While the Motion 20i is a statement in both aesthetics and sonics, the Monolith excels in delivering authoritative, immersive audio in a smaller package.

Speaker Comparison

When we immerse ourselves in the lush landscapes of high-fidelity audio, it's essential to consider how the design and engineering of a speaker influence our listening experience. Both the MartinLogan Motion 20i Tower Speakers and Monoprice Monolith THX-265B Bookshelf Speakers enter the fray with their unique philosophies of sound reproduction. The Motion 20i, part of MartinLogan's esteemed Motion Series, stands tall – quite literally – as a floor-standing speaker that exudes elegance and a penchant for detail. On the other hand, the Monoprice Monolith THX-265B, a THX-certified bookshelf speaker, promises to deliver a cinematic experience wrapped in a more compact form factor. But how do these two approaches impact the auditory narrative they sculpt?

Design and Build Quality

MartinLogan's Motion 20i boasts a sleek, modern silhouette that's bound to catch the eye in any room. The aesthetic is not mere window dressing – the build quality exudes sophistication, with the Motion 20i featuring a reinforced baffle and a clean, tight construction that reduces resonance. While the Monoprice Monolith may have a more understated appearance, it is robustly built as well. The THX-265B's cabinet is designed to meet the rigorous THX standards, ensuring minimal distortion and a focus on pure sound reproduction. Although the Monolith's look is more utilitarian, it is no less serious about delivering quality build and performance.

MartinLogan Motion 20i Tower Speaker
MartinLogan Motion 20i arrow (at

Sound Performance

When it comes to sound, the MartinLogan Motion 20i impresses with its Folded Motion tweeter, which provides a lightning-fast response and a broad soundstage that is hard to find in other tower speakers at its price point. The bass response is precise and articulate, thanks in part to the dual woofers whose performance is enhanced by the larger cabinet volume that tower speakers afford. Conversely, the Monoprice Monolith THX-265B is built to bring the theater home. The bookshelf speaker may not match the sheer size of the Motion 20i's soundstage, but it compensates with a focused and immersive surround-sound experience that adheres to the stringent expectations of THX certification. Its controlled directivity means that sound dispersion is meticulously managed, creating an enveloping field of audio where details are not lost to room reflections.

Application and Versatility

The MartinLogan Motion 20i towers are inherently versatile and capable of filling larger spaces with their expansive sound. They lend themselves well to both audiophile music listening and as part of a high-end home theater system. In contrast, the Monoprice Monolith THX-265B offers an excellent solution for those with limited space or who seek a speaker that can be integrated into a multi-channel setup without dominating the living area. Its bookshelf size makes it suitable for tighter spaces or as a dedicated surround speaker in a larger THX-certified home theater setup.

Ultimately, choosing between the MartinLogan Motion 20i Tower Speaker and the Monoprice Monolith THX-265B Bookshelf Speaker comes down to evaluating one's space, listening preferences, and the intended use. The Motion 20i offers a sumptuous and detailed sound worthy of the audiophile's ear, with a physical presence to match. The Monolith THX-265B, while more compact, delivers a no-compromise surround-sound experience that brings movies and music to life in a way that belies its size. Whichever path one chooses, both speakers stand at the vanguard of their respective categories, promising a transcendent journey through the world of high-fidelity sound.

Check Current Prices:

MartinLogan Motion 20i Tower Speaker
MartinLogan Motion 20i Tower Speaker
Monoprice Monolith THX-265B Bookshelf Speakers
Monoprice Monolith THX-265B Bookshelf Speakers

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Disclaimer: the speaker data listed on this website are correct to the best of our knowledge, but we do not guarantee the accuracy of the data. Please double-check any measurements with the manufacturer before making a final purchasing decision.