LUXKIT A505
¥ 59,800 (around 1980)
Commentary
A500 series tube type preamplifier kit.
Since it is a tube bulb type, a non-feedback amplifier is realized, and NFB is 0 dB over all stages, which brings out the taste of the vacuum tube itself.
Equalization, tone control and subsonic filter are CR-type.
All stages of the circuit are push-pull configuration, from the input stage of the equalizer to the output stage of the flat amplifier. The circuit is S. R. P. P. (Shunt-Regulated Push-Pull) suitable for vacuum tubes. This circuit automatically compensates for non-linear operation, eliminates distortion, keeps output impedance low, and allows output voltage to be high.
Equipped with a dedicated booster transformer to support MC cartridge.
This transformer was newly developed for A505 and is a compact type using high-performance permalloy core with a boost ratio of 20 dB (10 times / 0.2 mV) and designed for ease of use.
Equipped with tone bypass function and monaural output function.
Model Rating
| Type | Control amplifier kit |
| Circuit configuration | SRPP feedback SRPP |
| Distortion factor | Not more than 0.05% |
| Input sensitivity | Phono MM:2mV Phono MC:0.2mV |
| Signal-to-noise ratio | Phono MM/MC : 60 dB or more |
| Vacuum tube used | 12AX7 : 4 Pieces 12AU7 : 4 pieces |
| External dimensions | Width 289x Height 125x Depth 366 mm |
| Weight | 5.5kg |