Bring your LFT-8 up-to-date

The LFT-8c is the latest iteration of the LFT-8. This woofer update converts any older LFT-8 to the newest version of the speaker system.

This update adds a powered dipole woofer with DSP and the ability to smooth the low frequency response of the speaker in any listening room, time align the woofer with the midrange/tweeter, and improve the blend between the midrange/tweeter assembly with the new woofers.

The 8c woofer enclosure has both forward and rear radiating low frequency sources in isolated chambers.

DSP provides signals for the forward firing 8 inch woofer and the rear firing dipole woofer. This arrangement creates a gradient dipole radiation pattern which minimizes room modes for smoother bass response at the listening position and allows the user to tailor the frequency response and bass level for optimum performance at the listening position.

The DSP controls both a high pass filter for the front and rear woofers and a signal delay to the midrange panel to correct impulse and phase response.

While the woofer is self powered with an adjustable level setting, you continue to use your existing electronics to power the LFT-8’s midrange and tweeter through an updated crossover included in the new enclosure. The level controls allow low frequency tuning to your room size and listening taste.

This is a "bolt on" update which replaces your existing woofer enlosure, you will need interconnect cables, either XLR or RCA to connect between your preamp and the new powered woofer. Your existing amplifier and speaker cables continue to be used, remain connected to power the LFT-8 midrange and tweeter.

What is this update and why is the gradient dipole woofer significant?

The LFT-8 woofer has previously been a monopole and the LFT-8 midrange has always been a dipole. Dipoles naturally remove acoustic energy radiated to the side walls, which reduces early reflection arrivals at the listener improving clairity and detail.

The LFT-8c woofer update is called a gradient dipole, this woofer update is a dipole and gradient refers to the relative amount of low frequency energy radiated in the front direction toward the listener relative to sound radiated rearward which is out of phase creating a dipole low frequency source. This approach limits the, floor, ceiling, rear, and side wall bass radiation which minimizes low frequency room modes. The result is both smoother frequency response in the bass range where the woofer operates below 200Hz and tighter bass.

The goal is to direct the low frequency energy toward the listening position while reducing radiated energy to the sides and behind the speaker.

Three polar plots are shown below, 80Hz, 125Hz, and 200Hz. The hashed area represents out of phase sound radiated to the back, behind the speaker. The black outer line is with the gradient woofer disconnected for comparison. Notice in all cases below, side radiated energy is reduced and rearward directed energy is out of phase, some of which is cancelled. You are left with low frequency energy directed at the listener position. This method of reducing low frequency room modes is far more effective than almost any amount of bass traps you could install in your listening room.

The LFT-8’s modular construction provides owners of early versions of the speaker an update path to the existing production version. The new production version of the LFT-8 becomes the LFT-8c, and any LFT-8 existing owner can update earlier versions of the LFT-8 to the 8c without a cost penalty.

The LFT-8 update price is $1600, which includes shipping in the U.S.