Anniversary
Maestro
Integrated amplifier
The Maestro Anniversary was born in AIRTECH laboratories following the experience gained with the development of the Puccini Anniversary. The basic scheme is very similar, but with one important difference: the amplification chain is completely balanced by the input to the power stage, which is again unbalanced to connect to the speakers. This resulted in a doubling of the amplification and attenuation stages.
Even in the Master Anniversary all stages are zero global feedback. Feedback is also not used in preamp stages (as in the Puccini). The output power has been increased to 150W on 8Ω resulting in the downsizing of all driver and power stages that now use four transistor pairs per channel. However, the basic configuration remains as inverted cascode that is similar to a single gain stage followed by the output buffer.
The working point stability is maintained through a DC Servo that begins to work only at frequencies lower than a few tenths of Hertz (therefore totally out of the audio band). Such a refined circuitry, together with the selection of high quality components (military standard resistors, polypropylene audiograde capacitors made under AIRTECH specification, internal wiring with 7N OCC pure copper, pure copper gold plated output connectiors) helped to create a device that has the honor of being the heir of the glorious Maestro Integrated.
The Maestro Anniversary is a unique device, its remarkable power that always doubles as the impedance decreases and its extraordinary driving skills, are accompanied by a unique musicality and refinement and not easy to find in a so "muscular" amplifier.
The Maestro Anniversary is a unique device: its remarkable power and its extraordinary driving skills go hand in hand with exceptional musicality and refinement.
Anniversary
Maestro
Integrated amplifier
The whole amplifier is designed as if it made of three separate elements.
1- Power supply: made with a 600VA transformer for each channel. The bridge rectifier is made with ultra-fast discrete diodes of 50 A each. The filtering capacity is 16800µF per branch so the amplifier has a total of 67200 µf filter. At switch-on the current is limited by resistors variable with the temperature that after swoth-on are excluded from the signal path.
2- Amplifier: fully dual-mono also for ground connections and power supplies. The digital stages to control the volume chips are also optocoupled. The PCB copper tracks have a thickness double the standard to ensure the passage of large currents. The PCB routing has long been studied to optimize the signal paths and maintain the symmetry of the stages.
3- Preamplifier: as for the amps, the preamp stages are dual-mono. Immediately behind the input connectors were placed the channel switching relays followed by a discrete component buffer to isolate the amplifier from the source. The maximum acceptable input voltage is about 6VRMS. The buffers, balanced on both inputs and outputs, drive in class A the four chips (for each channel) of volume. The latter, as in the case of the Puccini are simply strings of resistances without any operational in them. This choice was made to not have any kind of global feedback inside the Maestro. After the volume control we have the real preamp stage that amplifies up to about 12db.
The three elements described above are physically housed on three separate boards so it’s like having a separate power supply, preamp and power amp.
The Maestro Anniversary is also available in RR version with analog volume attenuation based on relays and resistors for a further increase in sound performance.
Available in natural aluminium and satin black.
Nominal output power @8Ω
Attenuation 0dB, Bandwidth -3dB
Nominal output power @2Ω/1kHz
(Bandwidth limit 0Hz-80kHz/A weighted)
(230VAC)
(HxWxD)
