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Kronos AV
Kronos AV
TRIANGLE’s philosophy is to design and build speakers reproducing a lively and dynamic sound that puts you in the universe of your favourite artist from the first tone. Always looking for innovations, our team has a genuine desire to make you feel the music intensely and find yourself at the heart of a concert.
When you really feel a «live» experience, the music is taken to a new dimension; the soundstage opens, the musicians stand in front of you, each instrument is distinguished accurately and the music gives you the chills.

Triangle Thetis 300 Subwoofer
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  • Sale
  • Regular price £750.00
  • Available Worldwide Shipping

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.


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.


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.


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.


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.


  • Type subwoofer: Bass Reflex
  • Driver diameter: 20 cm / 8,3 inch
  • Bandwidth: 32 Hz – 120 Hz (+/- 3 dB)
  • Rms amplifier output: RMS 150 W - Classe D
  • Main inputphase: 100-240V / 50-60 Hz
  • Inputs: LFE - Line IN (L/R) - Speaker IN
  • Phase: 0-180 (2 positions)
  • Dimensions: 11,8 x 11,8 x 13,4 inch
  • Net weight: 23,4 lbs

We are still delivering orders as normal. When your order ships you will still receive tracking details. For UK shipments, Our couriers have procedures in place to ensure deliveries are arriving as quickly & safely as possible. Drivers can now sign for your parcels, however will notify you that they have arrived, in order to ensure you receive your parcel. Signing for the parcel has now been stopped temporally for hygiene reasons. Drivers are also working with customer instructions, so you can ask them to leave the parcel in a safe place (doorstep etc...) if you prefer not to come into direct contact with the driver.

There has been no changes to deliveries with Brexit. All deliveries to the UK mainland, Northern Ireland and the Republic of Ireland are operating as normal. No VAT or charges are applicable. 

We have several deomonstation areas in both of our branches. Please give us a call on 03435236169 or email to enquire about hearing products at your local branch. 

Please always contact us before to make sure the product(s) are available

Express Deliveries

Express Delivery is FREE on all orders over £50. Express Delivery offers delivery in 24-72 hours from time of purchase. We use premium couriers for this service, mainly DPD & Royal Mail. DPD will offer you a one hour window for delivery to make sure someone is at home, or you can reschedule the delivery if no one is around. 

Standard Deliveries

Here at Kronos AV, we have vast experience with e-commerce sales. Making sure that your parcel arrives undamaged is a huge priority for us. That’s why at Kronos AV, we only use premium couriers for all our orders. All our parcels are shipped with DPD or Royal Mail and are always sent Signed For to make sure it gets to the right person. 

If for any reason your parcel does arrived damaged, please get in touch, and we will be happy to get everything resolved for you. We are always on hand to help!


Delivery is FREE on all orders over £50. In order to offer FREE delivery to UK customers, we use several premium couriers to ensure your delivery arrives safe.

Most large orders (over 2kg) ship using DPD or DHL courier and smaller orders (under 2kg) by Royal Mail signed for services.

The most appropriate courier will be chosen for the items ordered to ensure the quickest possible delivery.

We can offer very generous trade in offers across the majority of our product range. 

Why not ask and see how much you HiFi is worth!

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If you have any question, please feel free to call us on 03435236169 or email