Audio Database


Lo-D HCA-9000
200,000yen(one-set, around the 1979 time)

The preamplifier of the tone-quality first-priority design which selected carefully the component partses which minimize the number of circuitries and constitute each of the circuitry block by the repetition of the careful audition.

Efficient and the toroidal transformer of low leakage flux are adopted as a power-source part.
Moreover, as a NF form, the constant-voltage electric current lowered source impedance, and has adopted the six-line independent power-feeding scheme which uses 1 set of constant-voltage regulated power supplies for all the amplifier respectively. Furthermore, a mass capacitor and the metallized polyesters film capacitor which was excellent in tone quality are connected to the output side in parallel, and the tone quality is raised.

The improvement in the quality of all the component partses is measured, and attention is paid to the selection of how to use a capacitor also especially in it, or a kind.
The styrene capacitor of 500V resisting pressure is used for the capacitor for phase compensations. In the circuitry where especially [ in tone quality ] a degree of incidence is high, a two-piece series was used and it arranges.
The electrolytic capacitor was made a metallized polyester film capacitor and flat amplifier in the two-piece back two back at the equalizer circuitry RIAA element, and the metallized polycarbonate film capacitor is adopted as a using and a power source.

The circuitry of HCA-9000 consists of MC head amplifier, an equalizer amplifier, and flat amplifier.
The interrupt control logic DC stream composition which has neither a coupling capacitor nor a mass capacitor of a feedback circuit in an input is adopted as these circuitries.

The differential circuit to which MC head amplifier part carried out 4 parallel connection of the high gm low noise FET to the first rank, the differential circuit in which the following stage has a current mirror circuitry, and the last stage have adopted the three-step stream composition of the SEPP output stage by a pure complimentary.
Furthermore, an input impedance is switched to a two-step so that MC cartridge of a very low impedance may also be matched.

The equalizer circuitry impressed the voltage of ±42V and has acquired the outstanding property by using of the linearity beyond maximum output 20V, the metals skin membrane resistance of a ±1% error, and the capacitor selected carefully in tone quality etc.

The coupling capacitor which examined the property enough is used for a flat amplifier part.

The Phono selector of front operation type is carried and the change of MC and man month is possible in the front panel.

Output is attaining low-power-output impedance-ization.

The off-position is established in the tapes monitor switchpoint.


Rating of a mode
Form Preamplifier
Circuit system MC head amplifier: interrupt control logic DC stream composition
Equalizer amplifier: interrupt control logic DC stream-composition NF type
Flat amplifier: interrupt control logic DC stream composition
Input sensitivity/impedance Phono1, 2 man month: 2.5mV/100 ohm, 22kohm, 47kohm, 100kohm
100pF, 200pF, 300pF, 400pF
Phono1, 2 MC: 0.25mV/30ohm, 100ohm
Tuner, Aux, Tape1, 2:150mV/47kohm
An Output voltage/impedance Rec out: 150mV/600 ohms (V or more [ A maximum of 20 ])
Output: 1V (V or more [ A maximum of 20 ]) / 30ohms (0--40dB)
Phono maximum permissible input
(1kHz, RMS, THD0.01%)
Phono1, 2 man month: 350mV
Phono1, 2 MC: 35mV
THD (20Hz - 20kHz)
Phono1, 2 man month : 0.005% or less (AT Rec out SFT Level 1V)
0.005% or less (AT Rec out SFT Level 4V)
Phono1, 2 MC : 0.01% or less (AT Rec out SFT Level 1V)
0.005% or less (AT Rec out SFT Level 4V)
Tuner, Aux : 0.005% or less (AT Output SFT Level 1V)
0.003% or less (AT Output SFT Level 4V)
Frequency characteristic Phono1, 2:RIAA±0.2dB (20Hz - 20kHz)
Tuner, Aux, Tape1, and 2:5Hz-100kHz+0 -1 dB
SN ratio (IHF, A network) Phono1, 2 man month: 90dB (AT Input SFT Level 2.5mV)
Phono1, 2 MC: 76dB (AT Input SFT Level 0.25mV)
Tuner, Aux, Tape1, 2:100dB (AT Input SFT Level 150mV)
Filter barrier property (only Phono input) 15Hz, 6dB / oct
Cross modulation distortion (60Hz:7kHz=4:1) 0.002% or less (AT Output SFT Level 7V)
Remains noise 5 microvolts or less
The semiconductor used Transistor: 81 pieces
FET: 24 pieces
Diode: 61 pieces
Supply voltage AC100V, 50Hz/60Hz
Power consumption 45W
AC outlet Power-switch interlock: Two lines, max150W
Power-switch un-interlocking.: Two lines, max400W
Dimensions Width 435x height 80x depth of 377mm
Weight 8.4kg