Audio Database

The pictorial image of Integra M-506

ONKYO Integra M-506
170,000yen(around the 1979 time)

Stereo power amplifier which adopted W and a super servo scheme.

The harmful component was made to feed back through servo amplifier from both by the side of + of an outgoing end, and -, and W and the super servo scheme to cancel are adopted.
+ A side cancels the super-low-pass component which is superimposed by the music signal and flows into a speaker, and is suppressing the occurrence of harmful cross modulation. Moreover, the servo loop by the side of - holds down the electromotive force which originates in a part for a part for the impedance which exists between the grounding side of an input, and the grounding side of an output, and the impedance by internal resistance, or the lead wire and others of a power source capacitor, and is generated, and it serves to send out only a music signal to an output-terminal.
By carrying out the servo control of the both ends by the side of an output, resolution is improved by expiry of the impurity which was carrying out the mask of the music signal, a harmful noise, and a distorted component.

An output stage is a three-step Darlington stream composition, and little distorted output is realized by using high fT power transistor. Furthermore, the performance characteristic of a power transistor is made into original linear switching of Onkyo, and the improvement in a distortion is aimed at much more.
It was developed in the intention that this scheme takes out the property of a first class in amplifier paying attention to only the final output stage usually working as a B class while employing the merit of B class efficiently,A bias is a scheme with the linear property developed by the basis of the design policy that it must fix, and demonstrates the performance excellent in combination with high fT power transistor.

The newly developed twin whined scheme large-sized transformer is used for a power-source part as a result of pattern research of influence in a tone quality. Moreover, as a result of investigating the correlation of a careful hearing and the physical properties of a material in consideration of importance, the low-impedance wide-range chemicon of a multi-tab scheme is used for the chemicon for a rectification as the printed circuit board and a low inductance circuitry made to link directly.
Furthermore, thorough low-impedance-ization, such as using a bus (bus-bar) line for the power feeding & power distribution to each section and an earth line, is attained.

In the case of a rapid transition in the continuous small-size width operation from a large swing operation, a heat ramp arises from the difference in heat capacity in each inter-block of a final. This rapid partial temperature change makes the bias-current value of a power part unstable, and affects especially a play of the Loule bell signal.
As a measure to this, the sensing bias circuit was earned on M-506 3 point to the output stage, a pre-driver part, a driver part, and three differences of temperature of a power transistor were detected, the bias is controlled, and the stable low-distortion drive is guaranteed.

While adopting a monolithic IC as a protection network and raising a stability, the overcurrent of a direct-current leakage voltage and the や power stage which appears in a speaker termination is detected, also in an emergency, a relay (a silver contact and a parallel using) is intercepted in an instant, and circuit component part is protected.
The speaker switching has prevented the failure of the dumping factor by switching a protection relay of SP-1 and 2 special purpose. Moreover, the low pass filter of the amount of direct-current-voltage detections, and also when polarities on either side differ by lower-right independency, it works.

The large-sized peek meter which performs a logarithmic comression and a peek hold by a monolithic IC with a sufficient stability is adopted.
Moreover, in order to acquire a high-speed responsibility, it is driving in the exclusive drive circuitry by operational amplifier.
The level can switch 0dB to 120W and 12W with a front switchpoint.

Examination by the hearing put into practice from a resistor, capacitors, the printed circuit board, and the lead wire for a product line to the solder for weldings is repeated and adopted from the semiconductor device and the transformer relationship.

Relay Parts

Rating of a mode
Form W and super servo scheme stereo power amplifier
<Amplifier part>
Effective output (20Hz - 20kHz) 160W+160W (4ohm)
120W+120W (8ohm)
Dynamic power (1kHz) 180W+180W (8ohm)
THD (THD, 20Hz - 20kHz) 0.003% or less (at the time of an effective output)
0.003% or less (at the time of 60W output)
Cross modulation distortion (SMPTE 70Hz:7kHz=4:1) 0.003% or less (at the time of an effective output)
Power Band Width (IHF-3dB, THD 0.2%) 5Hz - 100kHz
Gain 26.3dB
Frequency characteristic 1Hz-100kHz+0 -1.5 dB
SN ratio (IHF-A network input shunt) 120dB
Input sensitivity/impedance 1.5V/47kohm
Speaker load impedance 4ohm-16ohm
Dumping factor (8 ohms, 1kHz) 180
Output-terminal Speaker System1, 2
Transient killer operating time Power on:5sec
Power off:100msec
<Meter part>
Range switching x1 (0dB=120W)
x0.1 (0dB=12W)
Indicating range - 40dB - +4dB
Indication precision 0±1dB
- 10±2dB
- 20±3dB
Speed of response 100microsec (-infinity->0dB)
Carriage-return velocity 1sec (0dB->-20dB)
The semiconductor used Transistor: 47 pieces
FET: Two pieces
IC: Six pieces
Diode: 40 pieces
Power source AC100V, 50Hz/60Hz
AC outlet A maximum of 600W
Power-switch un-interlocking.: One line
Power consumption 190W (Electrical Appliance and Material Control Law)
The maximum Dimensions Width 450x height 174x depth of 400mm
Weight 18.5kg