AUDIO HUNGARY
QUALITON CLASSIC
A20i
Stereo, Class-A integrated amplifier featuring push-pull circuitry. The rated power output of the appliance is 20 W at the most, each side. The outputs at the rear panel can be connected to 8 Ω nominal impedance speakers. The design of the output transformers of the power amp enable to connect the amp with 4 Ω nominal impedance speakers as well. This entails a slight deviation from the parameters indicated in the technical data sheet.
At the front panel, the volume control potentiometer and the input selector rotary switch are connected to the same shaft. Indicators informing about the actual state of the amp are located at the front panel too. It can be monitored whether the appliance is ready for operation (if so, the LED next to the volume control turns from red to white light). The user is also informed about the actual position of the input selector unit. The amp is made of solid, 1.5 mm thick, polished stainless steel sheet.
A50i
This amp and its baby brother were reviewed by a very experienced audiophile as coming very, very close to a world famous $20,000 amp. Yes, the sound that good.
The A50i is a Class-A integrated vacuum tube amplifier with an output power of 2 x 50 W. The appliance can be connected to 4 Ω and 8 Ω nominal impedance speakers. The power outputs, based on output pentodes type KT 120, were tuned to the before-mentioned nominal loads through our in-house manufactured, precision winding output transformers. The bias control circuit plays an important role in the operation of the power output too. This curcuit monitors the quiescent current of the output tubes and adjusts it to a preset value. Thus, all four output tubes are in perfectly equal operation states.
The clearly arranged, minimalistic remote control was designed with this philosophy as well: the unique and aesthetical exterior design was always kept in mind and the usability was improved. Finally, a couple of words on the set of tubes we use: the audio signal arriving on the selected input of the appliance is received by vacuum tubes type ECC83. The driving voltage as well as its matching are produced by E88CC/6922s. In power output, the before-mentioned output pentodes KT 120 are in action—strictly in Class-A.
