Can someone offer their opinion on where i should place my surround speakers in my new setup.
Pic 1 or pic 2.
I can make it into a7.1 setup by placing the speakers in pic 1 then adding in the rears on the back wall but seeing as the romm is only 3.5m wide will i gain anything from it? Also my back is to the window/wall so will have to face the rears rather down.
All advice and opinions welcomed!
Given the wide bipolar dispersion characteristic of the 78DS then you shouldn't hear a great deal of difference between either position. However, putting them on the back wall might be slightly prefered.
I'd caution against angling a surround speaker down too much as it will collapse the ambient soundfield. As well as providing rear effects, the surrounds are designed to provide ambience i.e. generate lots of reflected sound waves in the room. This is why surrounds work better if placed higher-up (there's more bare wall available generally, and the sound isn't absorbed by sofas, people etc - so you will get plenty of multi-path reflections arriving back at the listening position = ambience). If you angle them down too much they will lose their ability to energise the room.
Balancing the two requirements can be tricky - especially if you're sat very close to the rear wall, as a high position runs the risk that you won't hear any direct sound from the rears. The best compromise might be to drop the height of the 78DS to a level that you can hear direct sound from them - usually two-three ft above head height if sat on the back wall - and then keep them parallel to the ground so that ambience isn't lost. Maybe ask someone to hold one and then raise/lower it whilst you are seated to test if you can hear it properly.
If this isn't possible, then you'll have to choose between either strong rear effects and poor ambience (i.e. angling them down sharply), or weak rear effects but good ambience (i.e. not angling them down).
Ultimately it's your choice, so long as you are clear what the choices are.
HTH