Well, having been inspired by Nick's mattress behind the settee and having had a chat with him and the good folks at GIK I have been playing with the conservatory furniture, stuffing duck down filled settee cushions and seats behind my mains, on the back wall and at first reflection points.
BB King Eric Clapton riding with the king album. Track 5 "three o'clock blues".
I took it all down after this track and played it again.
The result, the whole thing was Fuller and Richer (SWMBO's words) with the ad hock treatment.
The whole thing seemed just smaller on replay. The piano notes, which with treatments were hanging like large droplets in the air just fell flat.
This is a great quality track, and it still sounded good, but by comparison nowhere near as good as it was.
So it looks like some montster panels will be winging there way here soon as the start to my room treatment.
Thanks for your help Nick.
Chris smile

No 18 in the Hall of fame smile I have simple tastes; I am content to settle for the best:
GIK monster bass panels, rear wall. QNAP TVS 471i3. Roon into DSP5200SE via 210/ 218 zone... Explorer 2. Bluesound Pulse 2, Mini & Flex. 596v1, 518, Foxsat HD, Sony BDP, Pioneer 5090, 2 Chromecast's for LRB videos. MS200 to F80 for a Roon zone