UXL-18 - The Next Level



When it came time to ramp things up, back to the drawing board we went.  The criterion for this new design was clear.  As usual, it was based on the feedback we received from you, our clients - higher power handling, higher excursion capabilities, low distortion.  We went to work.



PS Voice Coil

The new PS voice coil made exclusively by IST, combines the very best technologies available.  It starts with a special non-metallic former, used because it does not generate eddy currents in the magnetic gap like metallic formers do.  This in turn reduces distortion significantly.  Heavy coated aluminum wire is CNC-spun using glues that have temperature ratings exceeding the magnet wire coating itself.  The adhesive is then heat bonded to ensure long lasting operation - a very time consuming and expensive process.  The PS design extended length topology ensures excellent heat dissipation and reduces power compression.


Low Distortion Motor

From our machine shop comes a CNC-turned magnet structure using quality North American steel parts, high energy ferrite magnets and strong adhesives.  Aluminum demodulating rings are applied to minimize distortion and a non-ferrous shield is placed within the motor to cut down on stray flux.  We then run this motor through our magnetizer four times to ensure proper saturation of the ferrite slugs.  Like the PS voice coil, these modifications are something you may never see, but the sonic improvements will be nothing short of spectacular. 


Cone and Spider

When dealing with the stress of very high excursions you need something that will maintain conformity.  We chose a dual layer craft pulp/carbon fiber diaphragm to achieve this goal as it provides both excellent damping effects and very high shear strength.  And let's face it, the carbon fiber is pretty sexy too!





Double thickness Conex spiders are used for maintaining linear stroke.  This material is extremely resistant to tearing regardless of the stresses placed on it.  Twin-run heavy tinsel leads are fed through the spider in a way that eliminates tinsel slap.  This is yet another time consuming assembly process that is performed by hand - no China sweat shop here!


The Result

We are confident the UXL-18 will meet your design criteria for the very bottom octaves.  Regardless of room size, it will deliver low distortion, intricate yet subtle bass tones for even the most devoted music listener.  For home theater, expect the UXL-18 to provide you with sub-sonic output into the single digits with the right setup.  Use a single UXL-18 in a Bass Reflex/EBS enclosure or multiple units in an Infinite Baffle configuration.  Whichever method you decide to use, you will achieve bass so low you will literally be able to count the sound waves as they pass you!




Option - The UXL-18 is available with a plain black gloss dust cap as well (no logo).  When ordering please specify which dust cap you would like.





76mm IST PS Series low distortion voice coil
Fs (Hz)


Cast aluminum basket

Re (Ohms)


Low distortion motor with demodulating rings



Internal stray flux shielding



Heavy Craft pulp/Carbon fiber cone



Extra wide heavy foam surround for high excursion

Cms (mm/N)


Conex spiders with double woven tinsel leads

Rms (kg/s)


Large spring loaded connectors

Mms (grams)


1200 watts RMS power handling

BL (Tm)


Excellent for home audio and home theater



34mm Xmax excursion for maximum output

Sd (cm^2)


Lp (2.83v/1m)




Suggested Box Sizes

Outside Diameter - 47cm (with rubber gasket)

Bass Reflex -

Mounting Diameter - 42.4cm


Depth -   24.1cm

Infinite Baffle - *


Price - $550.00

Out of Stock