Someone mentioned paper cones. I'd just like to remind you that paper cones were used with considerable success by AR and many others, and in fact, some argue that's the best material for bass drivers.
The fact that Frank's speakers use paper is not a problem, as I see it, what probably is a problem is that those paper cones are paper thick ("thick" is being generous). I dug up two woofers from my Korean made car some years ago and was astounded at their "thickness". But it sure explained why they sounded paper light.
Out they went and in came some JBL gear, and lo and behold, the sound improved no end.
On Belgian Frank's 2 1,500 VA transformers in two monoblocks. I am not really impressed because, as you said yourself, you use what is probably one of the most inefficient topologie around, meaning that you need them big and hefty for it to work properly. But respect to you for taking the time and trouble to use some high quality items, not just any old big transforemrs. That was, in my view, an excellent decision, if transformers are what our hearts are to us, it seems reasonable to me that you would not ask a man with heart problems to run a marathon.
On Australian Frank's PC speakers. I note that now they have problems not just up to 100 Hz, but up to 200 Hz. Over the next 10-15 pages of posts, I expect to learn that they are not so hot up to 500 Hz, and that there are some problems above 10 kHz as well. That reminds me of how my wife reports of expenditures after a trip. First report, oh, just a blouse. Second report, well, there was that pair of shoes as well, and the next day, yes, there were those T shirts too. She returned from Barcelona on Tuesday, and just yesterday, I was informed that she bought two pairs of shoes and two shirts for my son who was with her, as well. I expect to discover the actual damage done by Sunday.😀
You can't fool me, Aussie, I'm a made man who's seen the whole shebang many times. 😛
