While Opera audio has remained loyal to tube amplifier, analog source and high-efficiency loudspeakers, that listener experiences sound as very coherent and natural as the good old days.
Fifteen-inch horn loudspeakers remind of days gone by - the period before transistors ruled and tube amplifiers of a handful of watts had plenty of power to drive high-efficiency loudspeakers. With an output of 98dB at 1 meter from a single watt, M15's the sensitive type. A humble 300B-based 8-watt amplifier has enough oomph to party.
The M15 is a two-way speaker equipped with a massive 15-inch/ 38cm paper-cone woofer with a cloth surround and an extra ring forth the load . It uses a large wooden horn tweeter crossed over at 1000Hz to a 15" cone woofer. A 3" dome compression driver at the rear drives the pressed-wood horn that sits on an castanet woofer module, both with matching fine-furniture-grade walnut veneers. Similar as Altec but better than their metal horn design , the horn is not physically attached to the woofer module.
his construction design improved the direction character and the response off leaving the axis. M15 SE have also modified the part of woofer by creating an extra ring forth the load and gives mass weight to the bass.
The modified tweeters bring better frequency response. Both linearity and stability are improved by using a specialized cone imported from UK . The voice coils are also tailored and imported from UK as well, of which both copper and alum enlaced together, smaller space required, and can move in a smaller magnetic field to gain a higher magnetic energy as well as efficiency, the withstanding power has also been increased too.
Even though construction design is capable of excellent integration, a crossover remains necessary to define the transition between both drivers. For M15 line, opera audio relies on the simplest possible network design. A pure copper gilded 75uf circuit board and SCR capacitor and an oversized coil are all that separates the big unit from the tweeter. Simplicity and quality are the leitmotif. The wires of crossover are made of highly-pure, tailor-made copper wires, virtually oxidation free. This design reduces the internal impedance greatly and improves sound quality considerably.
With above improvement, the high frequency of M15 SE is more complaisant, the mid frequency is fuller and the low frequency is deeper. At the same time, It has possesses a better analytic and more detailed sound.