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Triangle Thetis 300

Name: Triangle Thetis 300
Brand: Triangle
SKU: caisson-de-grave-thetis-300
Rating: 3.7 (6 reviews)

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Subwoofer - Thetis 300

The Thetis 300 subwoofer is the essential part of your home theater set-up. Versatile, it will also be an ideal addition to your stereo system, for example to accompany smaller speakers. Equipped with a 20cm, downward-facing driver and an amplifier of 150W, this subwoofer in a compact format allows your set-up to considerably extend the bandwidth in the low frequencies. Using a bass-reflex principle, it keeps a limited volume while offering surprising performance.

The Thetis subwoofers feature numerous inputs, allowing them to be associated with all types of amplifiers. They include a direct LFE input, standard RCA, and high-level inputs for amplifiers with no suitable output. You can adjust the volume, the phase, and the frequency roll-off for a perfect fit with your main speakers.

Each Thetis subwoofer is supplied with a remote, an LED display on the front panel providing visibility of the sound setting.

It features an automatic power ON. Automatic STANDBY is also possible by activating the AUTO function of the subwoofer.

BASS-REFLEX CONFIGURATION

The Thétis 340 and 300 operate using a bass-reflex principle, extending their bandwidths even at low volume.

With a laminar port, airflow noise is significantly reduced compared to a classic tubular port.

SUCCESSFUL DESIGN

The transducers use composite membranes made of cellulose and carbon, that ensure high rigidity. Combined with oversized engines and controlled suspensions, the speakers have excellent power handling, reproducing all types of dynamics without any difficulty.

Equipped with the latest generation of Class-D amplifiers, the Thétis 340 & 300 respectively have a power of 250W/150W RMS, with a 400W/250W peak power. With steep crossover slopes, matching the Thétis subwoofers to your main speakers is easy.

The design of the cabinets is the result of a thorough vibrations study, conferring the Thétis 340 and 300 a remarkable sound.

PROVEN COMPATIBILITY

The Thétis subwoofers feature numerous inputs, allowing them to be associated with all types of amplifiers. They include a direct LFE input for home theater set-ups, the settings will then be made from your dedicated amplifier. They also feature standard RCA inputs for Hi-Fi set-ups, and high-level inputs for amplifiers with no suitable output.

You can manually adjust the volume, the phase, and the frequency roll-off for a perfect fit with your main speakers.

COMFORT OF USE

The Thétis subwoofers include a remote control for volume and standby. An LED display on the front panel provides visibility of the sound setting.

To save energy, an automatic standby is enabled after 20 minutes if there is no signal. As soon as a new signal is received, the subwoofer is automatically reactivated.

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Overall Score 74/100

Just Okay

Controlled, punchy low end gives the Thetis 300 surprising weight for a compact sub, its 20 cm driver and 150 W Class D amp reaching down to 32 Hz with tight dynamics and satisfying impact. Triangle pairs this with flexible connectivity (LFE, RCA, high‑level, crossover/volume knobs, remote) and a solid build that belies the compact footprint.

Pros

Strong low‑frequency extension and punch for an 8"‑class sub (20 cm driver, specified down to 32 Hz; 150 W Class D amp).
Extensive, hands‑on tuning and hookup options — LFE, RCA, high‑level input, crossover and volume knobs plus an IR remote — for flexible placement.
Well‑built, compact cabinet and respectable mass (10.6 kg) point to solid build quality for the class.

Cons

Pricey for a compact 20 cm‑driver subwoofer, which reduces perceived value versus rivals.
Limited evidence from independent reviews about how seamlessly it integrates with main speakers in-room.

Sound Quality

77/100

Bass

78/100

Based on the spec'd 20 cm driver in a bass-reflex cabinet and a specified bandwidth down to 32 Hz, expected extension and output are good for a compact 8"-class sub but not reference-level. No reviewer measurements provided, so score reflects likely real-world performance given size and 150 W amp power.

Dynamics

74/100

150 W Class D power and a compact sealed/ported design imply reasonable transient response and headroom for room-facing nearfield use. Without listening reports or measurements, dynamics are rated conservatively above average for this size.

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Integration

68/100

No review outcome language available about how it 'disappears' or blends with speakers. Spec list (crossover knob, volume, high-level input, LFE) supports easy tuning, but Features ≠ Integration; add outcome evidence or lower Integration.

Build Quality

80/100

Triangle is known for solid finishes; the unit's 10.6 kg mass and compact dimensions suggest a well-built cabinet and driver for its class. No review comments provided to confirm long-term durability.

Features Connectivity

82/100

Includes LFE, RCA, high-level input, crossover knob, volume knob and IR remote — comprehensive physical controls and connections for flexible placement and tuning. Passive baseline applied (no app/room EQ reported).

Value for Money

62/100

At the listed price (~749), the Thetis 300 is relatively expensive for a compact 20 cm driver subwoofer; without review praise calling it a 'no-brainer' or 'best in class,' value is modest. Lack of review-based performance endorsement lowers value score.