I own one and like it. I have read it was designed or built by REL for Rega, but do not know if that is true. It is suppose to be more musical than many subs, but it is the only one I have owned so do not know how it compares.
I am very happy with my Rega Vulcan. I think it works extremely well with music and adds guts to movie sound tracks. I use mission 731i bookshelf/stand speakers for front and rear stereo pairs, and it made a huge improvement to music when I added it. With movies it can add guts and substance to the sound track and if you are into bass heavy movies like say the Jurassic park trilogy is extremely impressive. Using test tones it goes very deep below 20Hz in my home cinema room 114" by 169". It is also very tightly controlled not boomy. I can not hear the subwoofer as the source of any sound when it is on, but can certainly hear the difference it makes when it is switched off. I have it sitting on a paving slab in the corner with the center of the sub about 18" from one wall and 13" from the other. I use the low level input volume set at just under 1/3, just below the first marker. I have the crossover set to just below the marker seperating AV from HiFi ranges.
It could do with more numbered markings on the dial for setting the crossover roll off, and more markings on the volume contol. The high level input recommended for hifi stereo is the same as some Rel subwoofers use, so it is a good idea to buy it with the cable if you can as they are not cheap. I did not get cables with mine and have not bothered buying the cable and connecting it via the high level inputs as I think it works fine using the low level inputs.
Originally many years ago I think the RRP was $1295. But I would not pay too much for one now as they can be had very cheap, I paid £80 including delivery a few years ago. But it did not come with any cables.
Rega Vulcan Specs
Enclosure volume 13 Litres Sealed. Drive Unit 200mm Long throw magnesium chassis,
Seperate switchable high level and low level input.
High Level Input Professional Switchcraft HPC Series (recommended for Hifi stereo use). High Level Gain control 0 to 37dB
Low Level Input Gold plated phono (two, recommended for AV home cinema use). Low Level Gain control 0 to 57dB
Amplifier Power 100 Watts RMS / 200 Watts peak
Frequency Range 17Hz to 240Hz depending on frequency seting. Up to 3KHz in processor position
Frequency Control marked from 30Hz to 230Hz, also marked HiFi, AV, Full Range