||65,000yen (March, 1968 release)
69,500yen (around the 1970 time)
Stereo power amplifier of a tube.
number is changed 3 times with EAA-2009, SU-2009, and SU-40A.
Mullard form is used for circuitry, the low noise tube 6267 is adopted as the
first rank, and low internal resistance and 12AT7 of a high amplification factor
are adopted as the driver stage.
Moreover, the thing with a cathode coil is
adopted as an output transformer, and high output of a pentode and coexistence
of low internal resistance of the triode are aimed at by covering cathode NF of
6dB over an output tube.
Moreover, NF of a main loop is 20dB and the
distortion at the time of an Output power is suppressed to 0.1% or less.
The circuitry is adopted as the bridge which combined current feedback
and a voltage feedback, and it can carry out variable of the dumping factor
continuously from infinity from +0.5 to -3, without changing gain.
factor variable functionality can choose the two-step of all the bands and a
bass region of 500Hz or less by the change of a switchpoint.
control of a right-and-left independency, the low-pass cut-off filter (15Hz or
less, 6 dB/oct), the speaker phase circuit changing switch, and the speaker
impedance circuit changing switch are carried in the interior of the front panel
|(from the left)
- Low noise-tube 6267 - high-L-tube 12AT7 - Output transformer
(from the left)
- AC outlet - Fuse - B speaker - A speaker - input terminal
||Tube main amplifier
||30W+30W (16 ohms, 0.1% or less of a
28W+28W (8 ohms, 0.1% or less of a distortion, 1kHz)
26W+26W (4 ohms, 0.15% or less of distortion)
||25W/25W (16 ohms 0.1% or less of a distortion, 1kHz)
24W/24W (8 ohms 0.1% or less of distortion)
22W/22W (4 ohms 0.15% or less of distortion)
|Frequency characteristic (at the time of 10W
||4Hz - 50kHz, and +0 -3 dB
|S/N ratio (A curve)
||Input short-circuit: 103dB
||- 3-infinity-+0.5 (succession variable)
It is a change possible to a perimeter wave number band (10Hz - 20kHz) and
500Hz or less (10-200Hz).
||Low-pass cut-off filter: 15Hz-6dB / oct
|The semiconductor used
|Thermionic tube :
||At the time of a non-signal: 85VA
time of 25Wx2 output: 145VA
||Width 360x height 150x depth of 330mm