how can I make the back wall transparent?

Pani, many thanks for the tip.

Everything you said in your post about energy, sound staging etc... - basically all the benefits you mentioned - is exactly what I am now experiencing.

However, I do have a couple of albums that seem to be a little bass heavy - so once I've determined that it is due to room acoustics and not the actual recording I'll definitely give them a try.

One album - Eric Clapton's "Unplugged" had some seriously bloated low frequency foot tapping going on in my room, which has now subsided to a more realistic level, but it could still do with some more "fine tuning" to get it perfect.

Cheers

Glad to hear the happy ending.

So substitute for determination and trial and error over time when it comes to managing room acoustics. So many ways to skin the cat.

I have no experience with them, but....

AudioKinesis Space Generators?

Open question...Williewonka's use of a vinyl material is resulting in diffusion of sound waves, yes?
Then shouldn't the material have folds in it, otherwise it could be reflective?

I'm thinking if used in my room, vinyl would cause deflection of sound waves.

Lowrider57 - the vinyl used - being soft like material - probably absorbs more than it reflects. Otherwise, as you stated above - it would simply reflect the sound back to the speakers just as the window did.

I do have drapes for the window, but they are very light and had little to no effect when I had them closed, so I am guessing most of the sound passed right through them.

Whereas the vinyl does not allow the sound to flow through it like the drapes.

Perhaps the sound is converted into motion?

It has to change into something and I'm pretty sure it's not heat :-)

I also tried some other thin fabric a while back - same results as the drapes

I get the roller-blind next week. It is a little lighter weight than the vinyl I used.

I will post an update once it's installed