Systems ListJTR SpeakersOrbit Shifter LFU

ManufactureJTR Speakers
System typeHorn
Driver Size18 "
Number of drivers1
External volume23.44 ft3
Dimentions (Width × Height × Depth)36 " × 22.5 " × 50 "
Weight225 lbs
Power4000 W
Aprox. Price$3499 USD


The Orbit Shifter LFU is a large front loaded horn design measuring 50 inches high, 36 deep and 22.5 wide. The design uses a single American made 18 inch driver with a 3 inch diameter voice coil, 30mm xmax and a very high motor strength of 256 (BL^2/Re). The moving mass is also said to be around 340g which is lower than normal for a driver with that type of motor force and excursion. The horn path is said to be about 14ft in length. The driver is installed under a hatch panel in the mouth of the cabinet. The horn mouth is huge and fires from the bottom of the front face of the cabinet. The cabinet construction is 15mm Baltic birch ply which is strategically braced. Total weight of the system is 225lbs. The internal amplifier is a Speakerpower Torpedo unit with a custom faceplate and control scheme made to JTR’s specs. It is mounted into the back of the cabinet towards the bottom. The amplifier is a highly efficient class D, full bridge module. The rating is 4000w into a nominal 4 ohm load and 7200w short term burst. The amplifier offers both XLR and RCA type inputs, a gain control, delay or phase control, detachable Powercon AC cable, a low pass filter adjustment and a low frequency adjustment. A 240 volt version is available for a $200 upcharge over the JTR direct price of $3499.

The LFU is a similar design principle to the similarly named, passive, professional version of the Orbit Shifter but other than sharing the Orbit Shifter name the two are quite different. The LFU version is “tuned” much lower and has the bigger cab required to reach lower. The OS-LFU matched or exceeded the JTR specs in most cases. The frequency response spec is a very tight 22-110Hz +/1dB. The measurements showed a response of 22-126Hz +/-1.7dB which is quite close. The “useable output” is rated at 133dB. The OS-LFU was able to produce 125-130dB at 2 meters during the long term output testing. A 1 meter result is typically what is reported and that would add 6dB to the results which would put 133dB right on the money if not a bit conservative. If the OS-LFU was driven all of the way to its limits it could be made to produce some distress noise from the driver. This happened below 25Hz only. The amplifier does not seem to have enough power to damage the driver mechanically though so the system should be safe from that aspect. However the headroom on this system is so great that it would be hard to imagine a pair or even a single of these being driven very hard in a domestic setting with a single OS-LFU likely being able to produce 120dB or more at 20Hz with the addition of only a bit of room gain. This is easily the most powerful active, commercial subwoofer that has been tested to date. In fact it is among the top handful of most powerful systems period. Of course the OS-LFU is also the largest and heaviest commercial system that has been tested but that is what it takes to make big bass