Audio Hungary Qualiton P200 Tube Amplifier
Overview
The P200 is a versatile, high-power amplifier, built on the KT-series beam tetrodes and our latest transformer designs. It features the latest iteration of our sophisticated Automatic Bias System for the four power tubes. The amp has two distinct modes of operation: Stereo and Bridge. In Stereo Mode, the P200 functions as a conventional stereo power amplifier with two unbalanced outputs for 4 or 8 Ohm speakers, delivering a maximum output power of 2 x 100 Watts. In Bridge Mode, the P200 operates as a monoblock power amplifier, offering a maximum output power of 1 x 200 Watts.
KT-Series Power Tubes
The amplifier's power block is specifically designed for KT-series power tubes, known for their high power, low distortion and magical sound character. This creates the perfect foundation for our amplifier, further enhanced by our custom output transformers for excellent low and high frequency performance. Moreover, our proprietary Automatic Bias System ensures seamless operation with KT90, KT120, KT150, and KT170 power tubes, so you’re free to choose your favorite without needing any modifications.
Custom Output Transformers
The transformers of our amplifiers are custom-designed and built in our in-house transformer workshop. Our output transformers are constructed using high-permeability, large cross-section toroidal magnetic cores, which undergo initial impregnation during the production process. Following this, the winding process begins, utilizing a multi-layered, sectioned, and specially arranged winding configuration. This meticulous design ensures optimal performance across both low and high frequencies. Once the winding is complete, the transformers are encased in metal shielding cans to minimize electromagnetic interference.
Custom Power Transformer
Just like our output transformers, our power transformers are also custom-designed and built in our in-house transformer workshop. We manufacture them with the same precision and attention to details: the high-permeability, large cross-section toroidal cores are also impregnated, and then the winding process follows. The parameters of the windings are designed to avoid saturation of the magnetic core and to ensure efficient operation even under heavy load conditions. It is important to note that we use double electromagnetic shielding for our power transformers. Finally, we employ the same epoxy compound used to pot the output transformers to eliminate mechanical vibrations and associated noises.
Automatic Bias System
This circuit continuously monitors the behavior of each tube and regulates the bias voltages accordingly, ensuring the smallest possible output voltage noise while guaranteeing the highest degree of linearity of the output stage. Additionally, it prevents the sensitive, high-permeability output transformer cores from saturating by precisely equalizing the quiescent currents of the power tubes. Furthermore, the bias system incorporates a built-in soft-start function, which prevents the tubes from drawing excessive current during start-up and eliminates pops and noises. The result is that no further adjustment is required once the electron tubes supplied with the unit have been installed; the Automatic Bias System takes care of everything.
Aesthetics
Stereo Mode
The amplifier has two distinct modes of operation: STEREO and BRIDGE. You can change the operating mode by reconfiguring the output connections and using the STEREO INPUT / BRIDGE INPUT selector switch to choose the input source for the selected mode.
In STEREO mode, the P200 functions as a conventional stereo power amplifier with two unbalanced outputs for 4 or 8 Ohm speakers, offering a maximum output power of 2 x 100 Watts. You can connect either an UNBALANCED or BALANCED stereo signal source to the amplifier in this mode.
Bridge Mode
The amplifier has two distinct modes of operation: STEREO and BRIDGE. You can change the operating mode by reconfiguring the output connections and using the STEREO INPUT / BRIDGE INPUT selector switch to choose the input source for the selected mode.
In BRIDGE mode, the P200 operates as a monoblock power amplifier with a BALANCED input. This mode concentrates the P200's total output power into a single channel: the two channels are fed from a monaural, symmetrical audio signal (BRIDGE input), and an 8 Ohm loudspeaker can be connected between the two amplifier outputs, bridging the terminals. The maximum available bridged, monaural output power is 1 x 200 Watts.
Input Signal Processing
In STEREO mode, the P200 functions as a conventional stereo power amplifier, allowing connection to either an unbalanced or balanced stereo input signal. These two inputs cannot be used simultaneously; if both are connected, the built-in control logic automatically prioritizes the balanced input, ignoring the unbalanced input.
In BRIDGE mode, the P200 operates as a monoblock power amplifier with a balanced input. In this configuration, the two channels of the stereo amplifier are driven by a monaural, symmetrical audio signal (BRIDGE input).
Special Components
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Tested and Selected Vacuum Tubes
The power tubes in all our amplifiers come in matched quads. The preamp tubes are selected for low noise, symmetry and minimum distortion.
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Gold-Plated Ceramic Tube Sockets
Ensuring reliable connections. -
Gold-Plated Audio Terminals
Enhancing signal transmission quality. -
Film Capacitors
We exclusively use film capacitors in our audio circuits for optimal performance. -
Ceramic Composition Resistors
These resistors are placed in critical positions to enhance reliability. -
Long-Life, High-Temperature-Tolerant Capacitors
Employed in our power supplies to withstand demanding conditions.
Tech Specs
Stereo Mode
18 Hz - 60 kHz (-3 dB, 100 Watts)
from milliwatts to rated output,
spanning 20 Hz to 20 kHz.
20 Hz - 22 kHz bandwidth, without weighting filter
> 110 dB below rated output
with A-weighting filter
1 Balanced STEREO IN
(for rated output)
0.48 Volts Balanced
40 000 Ohms Balanced
+35.4 dB @ 8 Ohms
Bridge Mode
20 Hz - 55 kHz (-3 dB, 200 Watts)
from milliwatts to rated output,
spanning 20 Hz to 20 kHz.
20 Hz - 22 kHz bandwidth, without weighting filter
> 110 dB below rated output
with A-weighting filter
(for rated output)
General
2 x 6922
4 x KT120 (KT150 / KT170 optionally)