Proton AA-2120 Dual Mono High Current Stereo 120 Watts per channel Power Amplifier

Price : RM 2380
Contact Simon Ting 012-3612507
In good working condition

The Proton AA-2120 is a powerful “dual mono” stereo power amplifier whose channels share only a cabinet, power cord, and on/off switch. The amplifier circuits for the two channels are completely separate, each on its own board and fed by its own transformer and power-supply circuit. The circuit boards are actually mirror images of each other, yielding a completely symmetrical layout on either side of the amplifier’s center line.

When the AA-2120 is turned off, its front panel is virtually featureless, with only the pushbutton power switch visible. When the button is pressed, two large output-level meters, softly illuminated in green, appear behind the normally dark glass window panel that covers most of the amplifier’s front surface. The meter scales are calibrated logarithmically both in watts, over a range of 7 milliwatts to 240 watts, and in decibels relative to the amplifier’s 120-watt rating into 8-ohm loads. Between the two meters, a pair of protection LED indicators appear if the amplifier is overloaded or its outputs become short-circuited.
The AA-2120 is a fairly compact amplifier considering its power ratings (120 watts per channel into 8 ohms, 180 watts into 4 ohms); its weight is more consistent with them, however. The amplifier has no fan, and its heat sinks are internal, but it is well ventilated and did not become unreasonably hot during our tests (and only mildly warm in normal listening).

The AA-2120 easily surpassed its power ratings in our tests. Encouraged by its obviously high current capability, we also ventured to test its dynamic output with 2-ohm loads, into which it delivered a staggering 440 watts per channel at the clipping point. The amplifier's frequency response was perfectly flat (within 0.01 dB) from 20 Hz to 20 kHz in one channel, and the other had an audibly negligible rolloff of 0.18 dB at 20 kHz. In checking bandwidth, we found that both channels were down 1 dB at 70 kHz and 4 dB at 200 kHz.

An amplifier with that kind of performance, including very low noise and distortion, is not likely to impart any sound character of its own to good program material, and the Proton AA-2120 was no exception to that rule. Although we did not have the companion AP-2000 preamplifier available, it seems likely that the combination of the two components would make a very compatible and listenable amplifier system.
在我們的測試中，AA-2120 輕鬆超過了其額定功率。受到其明顯高電流能力的鼓舞，我們還冒險用 2 歐姆負載測試其動態輸出，在削波點處，它每個通道提供了驚人的 440 瓦功率。在一個通道中，放大器的頻率響應在 20 Hz 至 20 kHz 範圍內非常平坦（在 0.01 dB 以內），而另一個通道在 20 kHz 處的滾降可忽略不計，為 0.18 dB。在檢查頻寬時，我們發現兩個通道在 70 kHz 時下降了 1 dB，在 200 kHz 時下降了 4 dB。

具有這種性能（包括非常低的噪音和失真）的擴大機不太可能將其自身的任何聲音特徵賦予良好的節目素材，Proton AA-2120 也不例外。儘管我們沒有配套的 AP-2000 前級放大器，但這兩個組件的組合似乎可以構成一個非常相容且耐聽的放大器系統