DENON POA-2200

Commentary

A stereo power amplifier with dual super no-feedback amplifier.

DENON's original dual super non-feedback amplifier is used for the circuit method, and the essence of amplifier technology such as complete DC configuration and non-switching method is put into it.

The dual super no-feedback circuit is designed to eliminate static distortion and inherent noise caused by nonlinear characteristics of amplification elements such as power transistors.
The structure consists of three servo amplifiers : a distortion servo circuit in which the N-channel and P-channel transistors in the power stage cancel each other's distortion, and a distortion servo circuit in which the total distortion appearing in the output stage of the speaker is eliminated. The main signal is transmitted to the speaker terminal without feedback, and because there is no NFB circuit, it is not affected by the back electromotive force from the speaker, and there is no increase in distortion when the speaker is connected.

F for pre-driver stage_TIt uses a 150 MHz high-speed transistor and a direct DC servo circuit with a fully capacitorless signal path (fully DC configuration) for higher slew rate.

The output stage adopts a 4-parallel push-pull configuration using a high-capacity high-speed power transistor of Pc130W.
In addition, DENON's original bias circuit is used to eliminate switching distortion and reduce crossover distortion.

The voltage amplification stage employs circuits and devices designed for high speed and wide dynamic range. In addition to three stage differential amplification using low-noise and low-feedback capacitance FET at the first stage, a Pc25W large-capacity transistor is installed at the final stage.
In addition, the Unity Current Interface (UCI) circuit is adopted to emphasize the interface characteristics of the amplifier stage and power stage. This circuit is a system in which the load of the voltage amplifier stage is always constant regardless of the operation of the power stage. By driving the power stage only with voltage, higher speed and lower distortion are realized.

The power supply employs a unique pure dynamic power supply system to effectively reduce dynamic IM distortion (intermodulation distortion) caused by interference between input signal and ripple current generated in the power supply.
It is also equipped with a 800 VA class large toroidal transformer and 8 10,000 μ F large-capacity block capacitors, and combined with a high-output power transistor to realize a drive that does not fluctuate even when the speaker impedance drops to 2 Ω instantaneously. In addition, the secondary winding and subsequent parts of the power transformer are made into a complete monaural configuration. After the left and right parts are taken out separately, they pass through independent large-capacity smoothing circuits and rectifier circuits, and are supplied to the predriver stage and power stage. This improves static and dynamic crosstalk characteristics.

The internal layout is twin monaural construction. The left and right channels are perfectly symmetrical with the power transformer at the center. The pre-driver / power stage, block capacitors, rectifier circuit, volume and input / output terminals are symmetrically laid out.
This eliminates the mutual interference between the small-signal line and the large-current line and between the left and right channels, as well as the non-uniform characteristics.

Equipped with two input terminals.
In normal mode, it is input to the voltage amplifier stage via the volume. In direct mode, it jumps to the volume and is directly connected.

A bar line multi-display is adopted in the center of the front panel. When the power is turned on, it blinks for a few seconds until normal operation is achieved and then falls. In addition, when an error occurs in the set, one of the four divided bars blinks to indicate the abnormal operation of overload detection, L/R DC detection and temperature detection circuit.
In addition, the newly developed overload protector is built-in, and abnormality is instantly detected.

Uses a speaker terminal that can be connected up to 6 mm core diameter.

Uses 37 φ 0.26 mm x power cords with polarity display.

Model Rating

Type	Stereo power amplifier
Rated Output (20 Hz ~ 20 kHz)	250W + 250W (6 Ω) 200W + 200W (8 Ω)
Input Sensitivity / Impedance	Normal : 1V/25k Ω Direct : 1V/50k Ω
Total harmonic distortion factor	0.002% (Output 100W, 8 Ω, 20 Hz to 20 kHz)
Cross modulation distortion factor	0.002% (Output 200W, 8 Ω, 60Hz/7kHz : 4/1)
Dynamic Power	600W + 600W (2 Ω) 450W + 450W (4 Ω)
TIM distortion factor	Below the measurement limit
Slew rate	± 500 V / μ s or more
Output bandwidth	5 Hz ~ 80 kHz (Output 100W, THD 0.03%, 8 Ω)
Line input frequency characteristic	1 Hz ~ 300 kHz + 0 -3dB (output 1W, 8 Ω)
Output impedance	0.1 Ω or less
Signal-to-noise ratio	124dB
Output terminal	AORb : 6 Ω ~ 16 Ω A + B : 12 Ω ~ 16 Ω
Self-diagnosis function	Diagnosis of abnormal temperature rise by display Bar line display
Power supply voltage	100 VAC, 50Hz/60Hz
Power consumption	340W (Electrical Appliance and Material Control Law)
External dimensions	Width 466x Height 186x Depth 420 mm (Including Knobs and Feet) Side Plate : 16x2mm wide
Weight	19.8kg