SB Acoustics SB20FRPC30-8 Full Range Speaker

Firstly I would like to thank Willy Hifi for the superb service. To explain, one of the drivers had a fault (which is very rare in my experience) but a quick phone call to Will explaining what the issue seemed to be, and it was replaced straight away. Thank you.
The fault in the driver caused the top end to get very harsh and aggressive at times, however now I have two working drivers, the sound from these Voigt pipes is just fantastic.

For those interested, I had to tweak the BSC circuit and increase the capacitor from 1uF to 2uF. This brought up the top end and made these drivers really sing. Open, airy and detailed and the sound stage has become even more defined than it was before.
The BSC gives these a slightly relaxed sound that is non fatiguing, but if you want more upper mid presence, lower the 6.8R. I wouldn't go much below 4.7 though as this makes the drivers sound a bit nasally and bright.

I can highly recommend these drivers to anyone wanting a single point-source unit.

The cab for the 8" is just over 1m tall (folded Voigt pipe), can't wait to see if SB release smaller versions of this driver (6.5 / 5.25).......??

Thanks again Will.

I bought these a while back with the idea of making a Voigt pipe speaker, finally got round to doing it. I ended up with a folded duct version to keep the height down to it would actually fit in my room!
The end result was mildly surprising. With a bit of baffle step compensation (1.5mH coil + 16.8R resistor (10+6.8) + 1uf cap (to lift the top end back up), I got a pretty good response.
One thing I will say, out of the box these sound a bit harsh but give them a few days to 'burn in' and the sound becomes a lot smoother. They are capable of huge bass and a very detailed top end considering that they have a simple whizzer cone.
The response image is nearfield in room, so it will be a bit lumpier than when measured outside or in an anechoic chamber (like I have one of those available!) The slight dip between 1.8k & 3.2k is not really noticeable and actually makes these pretty forgiving and non fatiguing. They also cope with poor recordings quite well.
The imaging is very accurate, but I do have a well setup/treated room, so most speakers tend to image well in my room.
I have provided a link to a YouTube video that I based my design on. I added some additional bracing and made the cab from 18mm MDF. A bit more stuffing was needed (compared to the video) and I ended up adding some stuffing to the port and some 'dodo mat' to some areas to tame the midrange and resonances.
All I would say is, don't think you can get away with putting these is the corners of a room, they need to able out in the room at least a .5 metre, preferably 1m to get the most balanced sound, so a reasonably large room is required to get the best from them.
These drivers are well worth the price, but make sure you don't skimp on the cabinet!