Reviewed in the United Kingdom on 1 February 2023
As other reviewers have stressed, it is important to spend the time and attention adjusting the low pass filter (the frequency response level [crossover point] at which the subwoofer cuts in with the 16' sounds) and the volume. As generally directed, it is sensible to set the bass on your amplifier to a neutral (0) level, i.e. no + or - adjustment to bass, as a starting point for calibrating the subwoofer, so that it works properly with the full available range.
The cables supplied might work with other people's installed system/amp., but in my case I had to buy a separate 1 RCA male to 2 RCA male cable to make it work properly. The 3.5 mm [vs. an RCA] to 2 RCA male cable supplied was not usable in my case as there is no suitable 3.5 mm socket on my amp., which does, on the other hand, have a dedicated subwoofer OUT socket, to which my new cable is correctly connected, and working well.
The other (2 RCA to 2 RCA) cable supplied with the unit generated feedback and distortion, although it sort of worked on some types music, but definitely not on others - and I was almost thinking of returning the unit altogether, if the replacement cable I obtained had not worked, but it does, and perfectly so.
Phase control is set at 0 ('normal'), unless you have a long cable and the subwoofer produces sound other than from the same plane as your main speakers.
Now that it has the right cable, and despite having been initially a little concerned about it with the 2 x 2 RCA plug cable, the system is working very well, and the gradual, proportionate response is very controllable, with a natural take-over of the lower bass registers from the main speakers, and the speaker and system as a whole is entirely free of background hum or noise. People who do not like music as much as I do have also commented that the effect is quite subtle, and can also be impressively powerful.
There are of course very detailed (11+ point...) subwoofer set-up instructions available online, but so long as one starts with everything set as above, and on low/zero levels and works up, a very good set of levels can be arrived at. I recommend also using feel - i.e. the levels at which your hand feels the subwoofer starts to vibrate - it is (pleasingly) a very fine tuning to set this point, and then just above that, for the required 16' bass effect.
As an analogy, anyone who plays an orchestral double bass, when doubling the cellos will know that it is a very subtle volume and level of precision that "tracks" the bass line an octave below, which is the most rewarding sound (the feeling of 'latent power') - simply enabling the octave to resonate almost with a life of its own, even at the softest levels, and which is a very wonderful thing.
It is also very possible to achieve a good level of (non-boomy) precision in the bass notes with this unit, as well as the different sound textures (i.e. the difference between a baroque string bass, tuba/bass trombone, synth bass, and bass guitar, for example.) One can of course turn up the bass volume on the subwoofer for specific pieces of music, as required....!
The music on which I want to hear more bass, is basically everything, ranging from rock and prog, to classical, big orchestral sounds, organ music, and electronic music. And so far, I am pleased to say that this subwoofer can handle all of it.
It is also important of course to test and adjust your system using a selection of music that actually does have a range and variety of proper recorded 16' sounds, and to start from very low volume and pass filter settings, and work up to the level that sounds right for you. (Generally: "less is definitely more"...!)
I have the volume on 1/4 of the max., and the pass filter (crossover) is set 1/2 way between 30 Hz and the max 160 Hz on the control knob dial (although the spec. suggests the range is 38-200 Hz.) but these settings adjustments will of course vary for everyone's different equipment, set-up, and personal tastes.
The sleep mode mentioned by some is not an issue for me as I would simply switch the subwoofer off when not in use... In any case the sleep mode seems to work/wake up completely correctly.
There is a sense of having a 'powerful, slumbering beast' that always has comfortably much more capacity in reserve than is being used, and could cope very easily with any levels of bass sounds one might wish to throw at it, and more.... if required.
In general, I would recommend the acquisition of a subwoofer, as a very cost-effective way of getting more out of an existing sound system, without massive, expensive upgrades of amplifier and speakers.
The unit actually measures approx. 25 cm (width) x 35.5 cm (depth, including space for the jacks and vol. / pass filter control knobs) x 28.5 cm (height) which is not as stated - I think the dimensions given online are the packaged size. It initially looked a little bigger than I expected when I picked up the box in which it was shipped, but it tucks away in a corner, effectively just about a square foot box, without taking up too much space, and the understated black design is very unobtrusive.
RE: auto standby, after a month or so, I also take the point made by other reviewers. I had the unit once switch to standby [the standby timing is set at 20 mins, with no bass signal] with low recorded volume and a passage of music with little/no 16'. I agree, it would have been better to be able to turn that function on/off manually. However, I actually don't mind turning the subwoofer on again to get the 16' back under such (fairly rare) circumstances. It may also be a question of adjusting the crossover point, so that the unit does not miss out on receiving a signal.
