Magico Q7 . . . wow

""""" 04-05-12: Stereotaipei
You cannot get driver with a 10dB higher efficiency than the Q5 without significant changes of design (in particular on the magnet).""""""""""

actualy you can not get driver with with 10db diferencies (assuming one is not 4inch midrange and other 18inch PA woofer) - its against law of acoustical physic. the spekakers,how ever can be easily made for diferent sensitivity maximum what is posible for same caliber driver 8-12inch) is 5db and it definatley will be in upper octaves (higher force means more midrange not all FR equally is gained) which is not important for low frequencies anyway.

stereotaipei, could you provide to me at least two drivers of the similar size which eficiency(measured with 1w input, not 2.83v) varies more than 7db in 50-300hz range? I have measured more than 160 diferent drivers on identical conditions, so I think I know a litle bit what I am talking about.

I see we are discusing in diferent worlds. I am speaking about main part of the speaker- speaker drivers(woofers)and there is no posibility more than 6db diferencies in low FR on same size woofers. You are talking about speakers eficienty where sensitivity can vary from arround 80db to 95db (in some cases like horns vs electrostats 75- 113db) because not speaker driver(s) determine speaker sensitivity but speaker designer -enginier. he can reduce (by changing BSC etc. ) or tilt up ( by adding more paraleled drivers, changing drivers interaction etc)

so we are both right. btw In your place,I would take manufacturer specified sensitivity values with salt and grain- unfortunately there very rarely tells truth.