Pioneer A-405R Amplifier

Probably, Mrs. Symmetry reigned over the Pioneer designers' minds, when they developed the appearance of this series of amplifiers. But, putting the volume control in the center, tone control and balance on each side of it, they, for some reason, threw over the original plan and spread other small details over the front panel, grouped them by functionality. The result turned out to be comfortable: stability of the appearance is a good supplement to the visibility of the faceplate of Pioneer A-405R. The inscriptions near input selector look quite unusual: in the form of column with sources' names, being slightly to the side from the switch key, that's why their belonging to the amplifier is not felt immediately, and the chosen source is identified by its own LED. Closer communication with Pioneer A-405R reminds a talk with cheerful gnome, who answers all the questions with a sly wink. Power on - Standby turns off, but the indicator of input selector and the pointer on the volume control handle light up. Push the "power on" button of Speakers, Loudness or Direct - the spark flashes merrily in the middle of each button. There is no muting in this model, whereas other modifications of this series (A-505R and A-605R, which look very similar to A-405R) have it. The remote control stands out among the rest, perhaps, by the existence of power on button not only for the amplifier itself, but also for CD player, tuner and tape recorder. The amplifier has the functions for control of multi tape recorder and CD changer. As for the rest, it is the usual set of control objects. External cascades of Pioneer A-405R are made on MOSFET transistors. Their use has its pluses and minuses here. Without going into technical wilds, let me notice that in the most cases MOSFET transistors are more resistant to short-circuit in loading than usual (bipolar), and also have transient response, similar to tube characteristic, and this attracts the engineers of Hi-Fi amplifiers. However, having same power voltage, MOSFET transistors show lower maximum capacity. Speaking about Pioneer particularly, the creators assure that employed transistors are free from this disadvantage to some degree. AFC of low-frequency tone control looks like hump with maximum on the frequencies just over 100Hz, when in other amplifiers you can see its constant increase (or decrease depending on control handle's position) down to the lowest frequencies. Listening "Flight of The Condor" performed by A-405R, you unwillingly think about replay of "nature" sound and about the impact degree of electronics on its transmission. Listening ancient melodies, performed by ancient or, more precisely, by instruments, made on old technologies, you want to feel their naive, primitive charm. The electronic overlay effect gives us hard highs and booming bass, making an impression of sound impaction. The electronics generates some tension at playing the song. But, as it is known, advantages are sequels of disadvantages. What was perceived as bass plangency in "To Elisa" by Beethoven turned out to be softness, hardness changes into strictness and asceticism of the play's melody picture, although there wasn't enough clarity for piano sound. Powerful and pressed bass in "Diner at Woolfie's" (Toscho) became more kindly; the guitar and the vocal in "Two ships" (Miller Anderson) showed that A-405R gives the freedom only within strict, certain limits, strongly holding the instrument in any attempt to stand out.