EI6GXB:

Valid point - Foster and Fostex are essentially the same company and confirmed suppliers of B&O's drivers...that's a good thing!

Although it will require some digging, I believe I'm onto something! I'll be measuring the exact thiele-small over the next few days though

If these turn out to be a match then we have a replacement for our CX units that will almost certainly be cheaper than B&O supplied ones, and is hopefully not about to be discontinued - top work!

yes, a lot of people think the CX100 drivers are 4 inch, but in fact they are slightly less in diameter, and are Foster 10cm jobs ( or 100mm ) as shown on the website

the VAS on model  434126 is 2.2L

the VAS on model  434127 is  3.2L

which ones do you have Liam ??