As above, ideally need to be less than 6″ deep, any advise or ecperience

i’ve got a pair of arcam muso’s that push out a rather good sound for their diminutive size.

Got some wall-mounted B&O’s for sale if you’re interested.

APF

I have a little pair of Monitor Bronze BX1s in my study.

Small, but punchy! Not in a massive room, though.

Can’t go wrong with Tannoy bookshelf speakers, might just be small enough.

Just checked..10 inch deep.. Bargain though

Tannoy

audio engine A2’s, tiny and sound great.

Mordaunt short m10 under 7 inch deep.

M10

The slightly bigger m20 is 8.5 inch deep

M20

Or another option which will definitely be small enough, it’s a pc speaker though but very good and has built in amp and auxiliary input

Creative t20 or t40

T40

Those Tannoys look very good at that price…

+1 monitor audio

Not made any more but if you can find some secondhand AVI Neutrons they are superb.

I was also going to suggest AVI Neutrons, but they will be difficult to find.

Ophidian make some good small loudspeakers.