Интегральные усилители — Rotel A11MKII

The Rotel A11MKII is a two-channel integrated amplifier combining a Class A/B power stage with digital and wireless connectivity. Its linear power supply is based on a large toroidal transformer built by Rotel, and the unit accepts analogue line sources, a turntable through a moving magnet phono stage, digital sources through coaxial and optical inputs, and phones or tablets over Bluetooth. Black and silver versions are made.

Key specs that matter

Rated output is 50 W per channel into 8 ohm and 62 W per channel into 4 ohm. THD and intermodulation distortion both stay below 0.03%, and the damping factor is 120. Line response runs 10 Hz to 100 kHz within -0.5 dB and +0.05 dB, the phono stage covers 20 Hz to 20 kHz within -0.5 dB and +0.3 dB, and the digital path spans 20 Hz to 20 kHz within -0.15 dB. A-weighted noise performance reads 90 dB at maximum and 95 dB at minimum volume on line inputs, and 85 dB on phono. Line sensitivity is 130 mV at 45 kilohm, MM phono sensitivity is 1.6 mV at 43 kilohm, and overload points are 4 V and 50 mV.

Engineering and use context

A Texas Instruments 32-bit/384 kHz converter serves the digital section. Coax and Toslink sockets take LPCM up to 24-bit/192 kHz at -20 dBFS sensitivity and 75 ohm impedance, and Bluetooth supports aptX HD and AAC. There are three line-level RCA inputs. On the front sit rotary bass, treble and balance controls with plus or minus 6 dB of range at 100 Hz and 10 kHz, source selection, and a 3.5 mm headphone jack driven by a dedicated headphone circuit. The supplied IR remote moves a motorised analogue volume control, and an RS232 protocol is published for system control. A multi-tap transformer powers the delicate signal circuits apart from the output stage, with physical and electrical separation in the layout. Rear panel details include a detachable IEC mains cord, heavy 5-way speaker posts and signal sensing auto power on and off. The case measures 430 x 73 x 347 mm, with a 60 mm front panel, and weighs 6.8 kg. The 120 V, 60 Hz US model draws 150 W, stays below 0.5 W in standby and its heat load is 450 BTU/h at 1/8 power.

Pairing

Digital outputs from a television or a disc transport go to the coaxial or optical socket, vinyl from an MM cartridge runs through the phono section, and phones stream over aptX HD without an extra receiver. Two 12 V trigger outputs can switch connected Rotel components.

Alternatives

Buyers wanting a USB input for a computer and 60 W per channel can look at the Rotel A12MKII integrated amplifier.