The amplifier is a push-pull Class AB mono power amplifier with two pairs shunt-wounded EL34 output power tubes per channel. It uses little global feedback. Signal goes first to the 6922 dual triode acted as input stage, then to the 6922 dual triodes acted as double drive stage. The 5687 drive the EL34 output tubes which are transformer-coupled to the load (In this case, the speaker.).
The Consonance Opera's are a terrific deal and look and sound much like the expensive audio jewelry you see at the best salons. Audiophiles should work for top sound and a bit of tube rolling and cable matching brings out the best from the Opera's. Wonderful metal work and facilities compliment exceptional sound from such a modestly priced pair of monoblocks. The mids and highs are elegant and detailed with the kind of sound you can take home to mother. The bass is good enough to satisfy and entertain unless you have only had a diet of solid-state sound your entire life. More powerful sounding than you would expect from 75-watts per channel indicating excellent design and R&D. I liked the Opera's and enjoyed many hours of beautiful, sweet music with them. I predict that you will, too.