RobinKidderminster:
Thanks for the suggestions. I think room acoustics are paramount. Maybe the settee against the back wall though it can't be changed. Soft furnishings are probably average for a domestic lounge.
I think there is room for expert discussion on room acoustics though at the same time few can alter them significantly. Especially those with wives !
Hopefully I will get some more discussion - even if my particular problem remains unresolved.
Thanks everyone - I'm not gonna give up !
Cheers
First off great that your not going to give up
Also that you realise the important of room acoustics and the effect that they have ,which is 50% + of the sound you hear.
Your speakers should be firing down the 18ft length of the room if possible, is there anyway that you can temporarily try your speakers like that to hear the difference it makes ,even if it is not practical permanently .
You also mention 11ft X 11ft ,square rooms are the worst dimensions to have ,although I suspect you mean that you use 11ft of the 18ft lenght of the room , this will unbalance the sound from the first acoustic reflection point of your room as well.
Correcting speaker position and room issues will give far better results and be cheaper than blaming the equipment.
You can demo a new amp and like it in the store but if you put it in a system that has bad positioning you might still be disappointed ,and more frustrated ,so a home demo sale or return would be essential in your position.
There is probably other things that may help , new speaker cables with silver apparently make systems brighter , moving the speakers ,even where they are by just a few inches , away from the back wall or corners can make big differences (don't have any speaker right in a corner though)
So many variables I know ,but please ensure you have maximised the positioning of what you have before spending money thinking a new amp or speaker will help, sure it will sound different , its bound to.
P.S As suggested by others consider setting up with a sound pressure meter and a test disc , especially speaker phase would be a good move and could show up any issues.
A meter is an essential piece of kit IMHO