QUALITON A50i – $7,500
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.
Out of three asymmetric and one symmetric inputs, one can choose the desired one using the front panel volume control and input selector rotary switch. The symmetric input features a mini XLR connector. In this case too, the entire volume control and input selector unit is in full harmony with the shiny polished casing of the appliance, bringing together functionality and aesthetics perfectly.
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 Tungsram 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.
Warranty: 2 years
QUALITON A20i – $4,750
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.
Warranty: 2 years
QUALITON PHONO – $4,499
A premium category vacuum tube phono stage with extreme low noise and distortion level, made for complementing the series Qualiton. On its input, the appliance can receive low level signals coming from moving magnet cartridges. Optionally at extra charge, with the help of the changeable card at the rear panel, the circuit can be re-configurated, this way, the appliance will be able to process signals coming from moving coil cartridges. In the signal transmitting circuit, signal processing is done by Tungsram ECC83 as well as Tesla E88CC double triodes. The standard RIAA correction is realised by a classic passive network between the amplifying stages. In this case, we did not use a negative feedback. The nominal input sensitivity of the appliance is 5 mV. In response to an input signal with an effective value like this, at the output ports an effective output signal value of the nominal 500 mV can be measured.
In order to achieve the lowest possible noise level, we have designed an external, stabilised power supply unit for the appliance with high capacity filter capacitors and high quality connectors. In this respect, we were not willing to settle for any compromises either, considering that this construction is much more advantageous than a usual configuration. In the case of the latter, the scattered magnetic field of the power supply transformer has a significantly adverse effect on the signal-to-noise ratio of the signal transmitting circuit, directly deteriorating the musical experience.
Warranty: 2 years
In January 2016, the impedance matching transformer of Audio-Hungary Ltd., specifically developed for moving coil cartridges of record players, was launched and prior to that, in November 2015, it was officially presented.
This passive device named Qualiton MC features a fairly aesthetical, shiny polished stainless steel outer casing. Inside of this casing, a pair of transformers is placed. Each transformer features a permalloy cover and the special winding, placed on the bakelite coil former makes it really unique. The high bandwidth is ensured by using quality winding and a special plastic, thus offering low distortion transmission of signal components, fed into the input of the matching transformer. The nominal amplification of the appliance is +24 dB. Having mentioned the input of the impedance matching unit: while designing this device we strove for the shortest possible signal paths, and among the input and output RCA sockets there is a highly accessible ground point.
Basically, the position, most appropriate for the actual cartridge, can be chosen out of three source impedance ranges: 2-10 Ohm; 10-50 Ohm. This solution proved to be far better than so-called ‘universal’ solutions using switches and parallel resistors. Important to know: as a special service of our house, the device Qualiton MC can be tuned to any cartridge type indicated by the customer ex works, as needed.
Warranty: 2 years
APR 204 – $1,999
The launching of the vacuum tube stereo power amp Qualiton APX 200 entailed the demand for developing a thoroughly classic vacuum tube preamp. The vacuum tube preamp Qualiton APR 204 is meant to meet this demand by not wanting to seem to be more than it is: it is in fact one indispensable element of the sound chain which was developed based on clear guiding principles and is able to evoke the classics of tube electronics.
At the same time, three audio sources with line level output signals as well as one signal source with MM phono output signal level can be connected to the RCA connectors at the rear panel. With the help of the audio source selector switch at the front panel, the user can determine, out of these four audio sources, which one of the relay-switched, volume-controlled signal should reach the output RCA connectors.
If the input selector unit is in ‘P’, i.e. PHONO position, the signal to be processed gets on the grid of the first voltage-amplifying vacuum tube through RCA connectors marked PHONO – thus, through the shortest possible signal paths. From here, in the before-mentioned classic way, the signal component gets on the grid of the second voltage-amplifying stage through a passive correction network between stages according to RIAA standard, realised exclusively with passive elements. We use both in the first and in the second voltage-amplifying stage double triodes ECC83/12AX7. Through an appropriate tuning circuit and volume control potentiometer, the output of the PHONO stage is connected to LINE stage, consisting of double triodes E88CC/6922.
Warranty: 2 years
APX 200 – $4,499
As the successor of the former amp BEAG APX 100, we have created the vacuum tube stereo power amp Qualiton APX 200 which is able to operate low impedance speakers. As opposed to the previous model, in the case of the Qualiton APX 200 we did not insist on the monoblock design. Instead, we regarded it as more favourable if we used a more compact and economical stereo version compared to the previous design.
The power of the appliance was set as 2 x 100 W, consequently it is able to dynamically operate even more insensitive speakers. The frequency response of the power amp is fully linear in the audio-frequency range, at nominal, i.e. 100 W output power, measured with sinusoidal waveform. The low frequency breakpoint of the frequency response is 15 Hz, the upper cutoff frequency is 100 kHz (-3 dB points). In the entire audio-frequency range, the total harmonic distortion is less than 1% and the signal-to-noise ratio of the appliance is typically higher than 101 dB. While developing this product, the listed technical parameters were attained due to carefully designed circuit arrangements, a selected set of vacuum tubes and an accurately dimensioned and a manufactured output transformer.
The protection of the vacuum tube set is handled with special care. The lifespan of the tubes can be drastically reduced by uncontrolled transient surges of current at the moment of power-on. Similarly, suddenly switching high anode voltage on non-preheated vacuum tubes can have an adverse effect on the lifespan. In order to eliminate those effects, the appliance is equipped with a slow-start circuit and an anode voltage delay circuit.
Warranty: 2 years (6 month for tubes)