Speaker levels

[arix]

Hi guys I thought I'd try and set my speaker levels manually I have read that 75db is the 'sweet spot" however I was unable to get my front presence speakers to 75 66db was the highest I could get with the master volume at 0db. So I decided to set all my other speakers to 66db in order to matain balance. Is this the right thing to do I have set the centre speaker a little hot to get clarity on vocals. My system is
Yamaha rx-a6a
Monitor audio silver 50 7g front
Monitor audio radius 90 rear
Monitor audio radius 200 centre
Monitor audio mass satellite x4
Svs pb-1000 pro

 

[arix]

It's the mass front height speakers that I can't get any higher than 66 they are 3.5m away for the main listening position and in the top corners of the living room