C7ES3 designed in a small bedroom....
I'm certain I've answered this before but stumbled across the images yesterday during a server tidy-up so here they are again.
Originally Posted by Kumar Kane
Attached are some pictures from 2006 of the back-bedroom in which the C7ES3 was 'voiced' i.e. the crossover optimised for the best bass/mid/top balance after the theoretical crossover work had been undertaken. They show what was to become the C7ES3 (I'd used some old tatty C7ES-2 cabinets as the prototypes for the C7ES3) and you can clearly see that the speakers are both backed up against the wall, and the left speaker near a chest of drawers. This is a real-world far from ideal purist situation, but it allowed me to complete the design of what has been a hugely successful model. And especially in Japan where the rooms are small and the C7 is beloved.
You will see the white box with many red/black binding posts. This is the instantaneous switch-over box. On the floor (very unprofessional, but that's how it was) are not two crossovers but four. That's because I had designed two entirely different crossover topographies, both theoretically good. I couldn't decide which would sound best from the measurements alone. So I had to build two for each speaker and make an instantaneous change-over between them.
Even then, the sonic differences were very subtle and needed careful concentration until one (pair) emerged as sonically superior.
Alan A. Shaw
Harbeth Audio UK