MartinLogan Motion 8i vs. Monoprice Monolith THX-365C

MartinLogan Motion 8i Center Channel Speaker Monoprice Monolith THX-365C Center Channel Speaker
$450 $500
Dimensions (H × W × D)
5.60” × 22.00” × 5.20”
142mm × 559mm × 132mm
9.70” × 22.90” × 10.80”
246mm × 582mm × 274mm
Power Type
Passive Passive
Frequency Response
70-23,000 Hz 65-24,000 Hz

Key Takeaways

TLDR Summary: In the realm of center channel speakers, audiophiles pit the MartinLogan Motion 8i against the Monoprice Monolith THX-365C. The Motion 8i exudes elegance with its Folded Motion tweeter, delivering crisp, articulate highs, and its compact form factor is a décor-friendly choice. In contrast, the Monolith THX-365C, THX certified, brings a hefty, cinema-grade presence to the table, with its controlled directivity and authoritative bass response. The decision between the two often hinges on whether one prioritizes the Motion 8i's nuanced soundstage and aesthetic or the Monolith's raw power and immersive sound that's engineered for a dynamic home theater experience.

Speaker Comparison

When it comes to creating an immersive home theater experience, the center channel speaker holds the key to unlocking clear dialogue and precise on-screen sound effects. It's the cornerstone of any surround sound setup and its importance cannot be overstated. In this quest for sonic perfection, two notable contenders stand out: the MartinLogan Motion 8i and the Monoprice Monolith THX-365C. Both of these speakers promise to deliver outstanding performance, but they approach sound reproduction in different ways, and each has its own set of strengths.

Design Philosophy and Build Quality

The MartinLogan Motion 8i exudes a sleek, modern aesthetic, with its distinct curved design and the iconic folded motion tweeter. This piece of engineering not only adds to the visual appeal but also contributes to the speaker's sound characteristics. The build quality is robust, with precision in every aspect, from the speaker grille to the binding posts. The folded motion tweeter, a hallmark of MartinLogan's design, offers a unique take on high frequency reproduction, delivering clarity and detail without the harshness sometimes found in conventional dome tweeters.

MartinLogan Motion 8i Center Channel Speaker
MartinLogan Motion 8i arrow (at

On the other hand, the Monoprice Monolith THX-365C is a beast built with one goal in mind – power. It has a more traditional boxy shape, but don't let the utilitarian design fool you; the build quality is just as solid and purposeful. The cabinet's construction is engineered to minimize resonance, thus ensuring that the sound remains untainted by vibration-induced coloration. The Monolith is THX certified, which means it meets stringent performance standards and is capable of reproducing movie soundtracks as the audio engineers intended.

Sound Performance

The MartinLogan Motion 8i, with its folded motion tweeter, provides a sound that is fast, detailed, and articulate. The high frequencies have an airy quality that brings a sense of space and dimension to recordings. Additionally, the Motion 8i's midrange driver is designed to deliver a balanced and natural sound, ensuring that dialogue cuts through even the densest of soundtracks. This center channel speaker is great for those who appreciate nuance and detail in their audio experience.

The Monoprice Monolith THX-365C, featuring its controlled dispersion and dynamic range, is meant for those looking for impact and consistency at high volumes. It's a speaker that can handle the roar of an explosion and the subtlety of a whisper with equal aplomb. The dual midrange drivers and tweeter work together to produce a coherent and focused sound that anchors the action right in the center of the screen. With the THX certification, you can expect cinema-like sound that is both expansive and precise.

Integration with Home Theater Systems

The integration of a center channel speaker into a home theater system is critical, and the MartinLogan Motion 8i is relatively forgiving in terms of placement. Its sound dispersion is wide and even, which means you'll get a consistent sound experience across a broad seating area. This flexibility is valuable in a home environment where the seating arrangement might not be ideal. Additionally, the Motion 8i's sound characteristics blend well with a wide range of other speakers, making it a versatile choice for various systems.

In contrast, the Monoprice Monolith THX-365C demands careful placement to truly shine. Its dispersion pattern is designed to match the stringent THX standards, which means you'll get the best experience when you're directly in the center of its sound field. This can be a double-edged sword: on one hand, you'll get a very focused and immersive sound for the primary seating position, but on the other, off-axis listeners might not experience the same level of clarity and balance.

Value for Money

The MartinLogan Motion 8i might come with a higher price tag, but for those who value precision and detail, it might be a worthy investment. The unique qualities of the folded motion tweeter and the overall build quality justify the expense for audiophiles who demand the best from their audio equipment. Furthermore, the investment in a MartinLogan is also an investment in a distinctive design that stands out in any room.

The Monoprice Monolith THX-365C offers a no-nonsense approach to sound that delivers on performance at a more accessible price point. Its THX certification means that you're getting a product that adheres to high standards of audio reproduction. For home theater enthusiasts looking for robust, cinema-like sound without breaking the bank, the Monolith THX-365C represents excellent value and proves that outstanding performance doesn't always have to come with a premium price tag.

Check Current Prices:

MartinLogan Motion 8i Center Channel Speaker
MartinLogan Motion 8i Center Channel Speaker
Monoprice Monolith THX-365C Center Channel Speaker
Monoprice Monolith THX-365C Center Channel Speaker

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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.