Audio Database

The pictorial image of Integra P-308

ONKYO Integra P-308
130,000yen(around the 1986 time)

Control amplifier which put into practice simple-izing and a high purity transmit aiming at the full-scale digital correspondence.

Direct-in direct out thought was put into practice, and circuitry simple with a multifunction is adopted.
After line system inputs, such as compact-disk input, are chosen with an Input Selector switchpoint, they do not pass along a muting, a balance volume, Mode, etc., but are direct sent into master volume flat amplifier.
Moreover, a tone control is adopting the direct tone scheme constituted only from a passive element using a part of volume circuitry, and has eliminated the amplifier for tones.
Furthermore, by the shortest distance, the input and output side also puts into practice and is performing the hardwired-connection product line.

Eight input selectors, and Tape1 special purpose and the independent double REC selector of Tape2&3 are carried.
Two outputs are carried, and since the MODE switchpoint is attached to each, they can take out the output the object for three-dimensional subWoofers, and for a center channel play.
Moreover, in Output2, the output attenuator of a right-and-left independency is prepared, and balance volume combined use is aimed at.

The super servo amplifier stream composition with the twin and FET input stage of an input hardwired connection, and a twin push pull output stage is adopted as circuitry. Moreover, the property which is supplying an advantageous light emitting diode bias in respect of a temperature coefficient or an occurrence noise as a material which obtains an about 2V constant voltage, and was comparatively excellent in the small electric current is realized.

In order that an equalizer-amplifier part may treat a minute input signal, it is considering an input stage as a double twin and an FET stream composition with a thermal stabilizer, and puts low-noise-ization into practice further.

A power-source part has eliminated the cross interferencee by performing a block power feeding for exclusive use by another coil in each amplifier, respectively while aiming at the low-impedance power feeding by a satellite power source.
Moreover, in order to eliminate a break-in of the noise from a power source, the noise separator was formed between the primary sub-s - of a power transformer, and the common mode noise which invades from a primary side is prevented. Moreover, the normal mode noise is removed by the charge noise filter.
Furthermore, it dissociates from an amplifier circuitry and a power transformer, a charge noise filter, and a rectification and a smooth block are covered with a shielding case, take out only DC line, are supplying electric power to the voltage stabilizer, and have eliminated the electromagnetic interference of a power-source part.

The signal in phase transformer is adopted as both by the side of the input side / output, and the common mode noise which invades from the outside is removed. Moreover, the interference between L/R produced in the earth line of the pin code which connects between equipments is eliminated, and the separation is raised.

The direct tone control circuit with contrabass is adopted.

The cartridge selector of MC2 position and man-month2 position is carried.


Rating of a mode
Form Preamplifier
Input sensitivity/impedance Phono MC: 160 microvolts/100ohm, 220ohm
Phono man month: 2.5mV / 47kohm, 100kohm
compact disk, Tuner, Line, Tape play:150mV /, 20kohm
An Output-power voltage / impedance Tape rec: 150mV/560 ohm
Output: 1V, 6V (maxima)/160ohm
Phono maximum permissible input
(THD0.05%, 1kHz)
Frequency characteristic MC: 4Hz-150kHz+0.2 -3dB
man-month: 1.8Hz-170kHz+0.2 -3dB
compact disk, Tuner, Line, and Tape:0.8Hz-170kHz+0 -3 dB
THD (20Hz - 20kHz)
3V output, Vol-30dB
MC: 0.003% or less
man month: 0.0008% or less
compact disk, Tuner, Line, Tape: 0.0005% or less
Cross modulation distortion (at the time of an Output power) 0.003% or less (SMPTE, 70Hz:7kHz=4:1)
SN ratio (IHF-A filter)
Input short-circuit
MC: 76dB (320 microvolts)
compact disk, Tuner, Line, Tpae: 106dB
Tone control (Vol-20dB) Bass: ±10dB (20Hz)
Bass Selector Bass:450Hz(Boost/Cut)
Treble:±8dB (20kHz)
Filter High: 7kHz, 6dB / oct
Transient killer operating time Power on:7sec
Power off:100msec
AC outlet Power-switch interlock: Two lines, a total of 800W
Power-switch un-interlocking.: One line, 200W
Power source AC100V, 50Hz/60Hz
Power consumption 22W (Electrical Appliance and Material Control Law)
Dimensions Width 465x height 103x depth of 403mm
Weight 8.5kg