QUALITON A50i. Built-in 50w output tube amplifier. Based on the KT120 pentods. Own transformers.

Class A built-in tube amplifier with a power output of 2 x 50 W. The device can be connected to speakers of nominal impedance of 4 Ω and 8 Ω. The power outputs, based on KT 120 type output pentodes, were adjusted to the rated loads earlier through the company's manufactured precision wound output transformers. The bias control circuit also plays an important role in the output power operation. This circuit monitors the quiescent current of the output tubes and adjusts it to a preset value. Therefore, the four outlet tubes are aligned so that they operate perfectly the same.

Of the three asymmetric inputs and one symmetric, the desired one can be chosen with the front panel volume control and input selector. The symmetrical input has a mini XLR connector. Also in this case, the entire volume control unit and input selector is in total harmony with the polished and shiny housing of the device, which perfectly combines functionality and aesthetics.

The minimalist remote control was designed with this philosophy: unique and aesthetic exterior design was always taken into account and ease of use was enhanced. Finally, a couple of words in the set of applications used: the audio signal that reaches the selected input of the device is received by Tungsram ECC83 type valves. The driving voltage, as well as its matching, are produced by E88CC / ​​6922s. On the power output, the KT 120 output pentodes mentioned above are in action, strictly in Class-A.

Technical characteristics:

Rated output power: 2 x 50 W, stereo

Total harmonic distortion <0.75% (f = 1 kHz, rated output power)

Frequency response 30 Hz - 100 kHz (-3 dB, rated output power)

Input sensitivity 425 mV, unbalanced input

Number of input ports 3 unbalanced input per channel, 1 balanced input per channelNumber of output ports 1 output terminal pair per channel, 1 line level output per channel

Gain +33.5 dB (8 Ohm); + 25.5 dB (4 Ohm)

Input impedance 10 kOhm

Nominal load impedance 4 Ohm and 8 Ohm

Output polarity non-inverting

Signal-to-noise ratio> 95 dB output noise less, than 1 mV

Power requirements: 300 W

Tubes required 4 x KT120; 4 x E88CC / ​​6922; 2 x Tungsram ECC83

Weight: 25 kg

Dimensions: 35 x 21 x 40 cm