ASTOR
AS-6550PM Stereo Pre-main amplifier

This is a middle class pre-main amplifier from Astro Electronics.
It is firmly in the tradition of Astro Electronics' highly transparent amplifiers with no ornamentation.
It has been overhauled by the manufacturer. The warranty period is as long as 5 years. (Only vacuum tubes are guaranteed for six months)
The whole body is both glossy and black, which is cool. This AS-6550PM is an amplifier specially ordered by the previous owner, and was designed to fully reproduce the large diatonic speakers of nearly 50 years ago by changing the capacitance of the capacitors and resistors to extend the vocal range in the mid and high frequencies, while extending the low range by adjusting the voltage of the B power supply and others. The sound is now more robust.

Condition	Almost flawless and beautiful
Accessories	No accessories

Vacuum Tube	12AX7T x2, 12AU7x3, 12AX7 x1
Transformer used	PT-300x1, HWC-30-5x2, C-1-400 x1
Frequency response	10Hz~60kHz
Output	25W x 25W
Residual Noise	Less than 1mmV/1W
Input	PHONO, CD, LINE1, LINE2
Input Impedance	100kΩ
Weight	24kg
Size	W470xH150xD370mm