McIntosh MX 110

 The MX110 combines in one unit an extremely low-distortion preamplifier with a highly sensitive FM multiplex stereo tuner. Every desirable feature of a tuner and a preamplifier is included in this design. Interstation noise suppression, tuning indicator, FM multiplex indicator, individual channel bass controls, individual channel treble controls, electronic phase switch have all been engineered into the MX110. The INPUT SELECTOR gives you a choice of six different program sources. The MODE SELECTOR is a newly developed control which makes it very easy to balance a stereo system. It is designed to add left to right for monophonic operation, to control the left to right stereo perspective or to compare the left and right channels of a stereo program. The loudness of the phono channels and the auxiliary channel may be balanced to the tuner loudness.  These adjusting controls are located on the top of the MX110 behind the front panel. By releasing the PANLOC buttons on the front panel, you can slide the MX110 out of its mounting until the second latch engages. The top mounted LEVEL set controls are now available.

The Mclntosh designed PANLOC system is the first professional installation technique to be used on stereo instruments. The PANLOC system gives you absolute ease of installation, operation, and maintenance.

The Mclntosh MX110 is a beautifully engineered control center for the finest stereo sound systems. The extreme care in manufacturing, in layout design and in thermal engineering promises the usual Mclntosh extra values of reliability, performance, and long life.

 The MX110 combines in one convenient instrument an FM Tuner, a Multiplex Decoder ana a Stereo Preamplifier. You mount only this one unit, connect it to your power amplifier and speakerss and you're ready to go.

The electronic circuits in the preamplifier are so skillfully engineered that a wave-form analusis at 3 volts output shows typically only 1/20th of 1% distortion 20 cycles through 20,000 cycles. The stability of the tuner circuits has been improved to the point that A.F.C. is no longer needed. Sensitivity is also increased over previous models. The MX110 uses a newly developed indicator which lights whenever the tuner is centred on a station broadcasting the 19KC carrier for miltiplex stereo. The control circuit for the indicator respondes only to the 19KC and is insensitive to noise.

The MX110 also uses the new, exclusive McIntosh PANLOC method installation. The PANLOC system gives you absolute ease of installation, operation, and maintenance. PANLOC is the first professional installation technique to be used on stereo instruments.

The MX110 is a model of convenience, careful planning and rigorous manufacturing methods.

 The radio-frequency amplifier of the MX110 is a "cascode" type circuit. The circuit is specially designed to amplify weak signals with less noise and distortion. By carefully tuning this RF amplifier during manufacturing and controlling other circuit constants, spurious response rejection is improved. The high-frequency oscillator mechanical layout is engineered for minimum response to temperature variations. In fact the combination of mechanical and electronic design is so unusually good in this circuit that automatic frequency control is not needed in the MX110. The mixer output is amplified by four flat-topped intermediate frequency amplifiers. The transformers used in the LF. amplifiers are designed for maximum adjacent channel rejection, for electrical stability, and for electrical and mechanical resistance to shock and vibration.

The R.F. and I.F. circuits of the MX110 are completely shielded and exceed the FCC requirements for suppression of oscillator radiation. Either a 300 ohm or 75 ohm antenna may be used with the MX110. A VHF television antenna which is suitable for FM reception can be connected to the MX110. In the MX110, a new type of mechanical tuning assembly gives smooth flywheel tuning. By controlling the relations between mass and mechanical resistance, and dividing work loads in the dial drive system, it becomes nearly impossible to detect any backlash. Yet the entire dial drive is a model of mechanical stability. For smooth, quiet action and extended life with virtually no wear, a teflon lined dial pointer carriage and nylon pulleys are used in the dial cord assembly.

 The multiplex decoder uses a special Mclntosh developed detecting circuit. One of the advantages of this circuit is the elimination of the critical adjustments necessary with commonly used matrixing methods. This circuit detects the L+R sidebands and automatically matrixes the recovered information with the L+R main carrier signal. This circuit then yields the left and the right program with maximum separation. A temperature stabilized 19KC amplifier locks-in a highly stable push-pull synchronous oscillator. Apart from other advantages, this method provides greatest noise immunity. Balanced detectors cancel 19KC and 38KC components in the output and insure low distortion.

A three-section sharp cut off filter rejects SCA interference and reduces susceptibility to spurious signals.

The MX110 has an MPX stereo indicator that lights when the dial pointer crosses a station broadcasting MPX stereo. A unique circuit using a transistor operates the MPX stereo indicator. The transistor is controlled by a differential detecting circuit that amplifies the 19KC pilot signal. This circuit automatically discriminates between the 19KC signal and noise.

 The MX110 audio amplifier consists of three negative-feedback amplifying sections in duplicate for the left and right stereo channels and a separate L+R monophonic amplifier. The first section in each channel is a feedback preamplifier used to amplify and compensate for the input signals coming from phonograph pickups or tape heads. Level set controls are connected into the output circuit of this preamplifier section when the INPUT SELECTOR is switched to PHONO 1 or PHONO 2. These controls may be used to maintain uniform loudness between phono and tuner inputs. Skillful layout, grounding, and shielding for low-hum pickup, metal film resistors, low-noise tubes and extreme care in manufacturing combine to reduce noise and hum in the input amplifiers. The second amplifier section in each channel is a cathode follower. The sharp cut-off (18db per octave) rumble and high-frequency filters are associated with this section. Inputlevel set controls for the auxiliary inputs are associated with this section. All the level set controls are conveniently accessible The third amplifier section is a two stage negative feedback amplifier. The variable bass and treble controls are included in the feedback loop to maintain the lowest possible distortion. For example a wave meter analysis of the three amplifier sections of the MX110 shows less than 1/10 of 1% distortion at 3 volts output. The MODE SELECTOR, balance controls and left and right outputs are associated with the third amplifier section. The L+R monophonic amplifying section is a feedback summing amplifier. It supplies monophonic output as well as L+R output.

The power supply of the MX110 has received very special design attention. Three separate rectifier circuits are used. First, a full-wave rectifier supplies D.C. to the heaters of all audio stages. A second bridge rectifier supplies D.C. to the anodes of the audio stages. Then a third full-wave rectifier supplies D.C. to the tuner stages. This elaborate power supply design insures the lowest possible background hum level and also the maximum stability. In addition to this careful work the power transformer uses special magnetic shielding to minimize possible hum pickup in the MX110 as well as in any other equipment used with it.

TUNER SPECIFICATIONS

Sensitivity:  Better than 2.5 microvolts at 100% modulation.

R.F. Amplifier:  Cascode.

LF. Amplifiers:  Four.

Limiters:  Two.

LF. Bandwidth:  200KC flat top.

LF. Transformers:  Mechanically captive.

Muting:  LF. injected.

Tuning Indicator:  Tuning is indicated by an electron ray tube.

Frequency Response:  Within ± 1db 20 to 20,000 cycles. (Including 75 microseconds deemphasis.)

Hum:  Greater than 70db or more below 100% mod. (Audio tubes have D.C. on the filaments.)

Drift:  Less than 25 KC.

Ant. Input Impedance:  300 balanced, 75 ohms unbalanced.

Radiation:  Substantially below F.C.C. requirements.

Distortion:  Less than 0.6% distortion at 100% modulation, ± 75KC deviation above 2.5 microvolts at antenna.

MULTIPLEX DECODER SPECIFICATIONS

MPX Decoder

Hum Level :  Better than 60db below 100% stereo modulation.

Distortion :  Less than 0.3% (Multiplex Decoder only).

Channel Separation :  Better than 30db at 1000 cps.

Suppression of Pilot (19KC), and Carrier (38KC) :  Greater than 40db below 100% modulation.

Front Panel Stereo Indicator Light :   Activated by 19KC pilot carrier only.

AUDIO SPECIFICATIONS

Inputs (Total 5 each channel):

AUX.; PHONO 1 MAG. or XTAL; PHONO 2 MAG.; TAPE HEAD; TAPE MONITOR.

Outputs:

Main Stereo Outputs, 1 Tape Stereo Output, 1 L+R Output.

AC AUX Outlets:  1 unswitched, 2 switched.

Controls

Input Selector: Total 6 positions: AUX, MPX, FM, PHONO 1, PHONO 2, TAPE HEADS.

Mode Selector: Total 7 positions: L TO L&R, R TO L&R, STEREO REV., STEREO, MONO, L+R TO L, L+R TO R.

Tone: Dual treble and bass negative-feedback controls with slip clutch for independent

adjustment of each channel.

Bass Boost :  15db at 50 cycles.

Bass Cut :  18db at 50 cycles.

Treble Boost :  15db at 10,000 cycles.

Treble Cut :  15db at 10,000 cycles.

Balance: Turn to right to emphasize the right channel. Turn to the left to emphasize the left channel.

Phase: 2 positions: NORMAL or REVERSED:

Changing phase does not increase distor- tion. H.F. Cutoff Filter: 2 positions: Flat, or 5KC cutoff. (20db per octave.) L.F. Cutoff Filter: 2 positions: Flat, or 50 cycles cutoff. (20db per octave.)

Loudness: Fletcher Munson compensation.

Tape Monitor: 2 positions: IN and OUT. For comparison of recorded tape with program source after recording.

Tuning: Flywheel tuning—no backlash.

Muting: 2 positions: IN or OUT for interstation noise suppression.

Level Set: Three left and three right controls. 2 for AUX, 2 for PHONO 1, and 2 for PHONO 2. These controls are located back of the front panel on the top of the MX110.

AC Power—Concentric with BALANCE control: ON-OFF.

ELECTRICAL SPECIFICATIONS

Frequency Response:  ±½db 20 to 20,000 cycles.

Distortion:  Less than 0.2% at rated output.

Hum and Noise:

High-level inputs :  80db below rated output.

Low-level inputs :  less than 3 microvolts at input terminals.

Input Sensitivity:

AUX :  0.3 volt at 200K.

PHONO 1 :  3 millivolts at 47K.

PHONO 2 :  3 millivolts at 47K.

TAPE HEAD :  3 millivolts at 220K.

TAPE MONITOR :  0.3 volt at 100K.

Outputs:

MAIN :  3 volts 2 in parallel each channel.

L+R :  3 volts.

TAPE :  From FM at 100% modulation 0.9 volt from PHONO when cartridge output is 9.0 millivolts—0.9 volt; with rated input —0.3 volt.

POWER REQUIREMENTS: 105-125 volts AC 50/60 cycles; 75 watts.

FUSE: 1 amp. Slo-Blo.

TUBE COMPLEMENT

1 6DS4 R.F. -1 amplifier (nuvistor)

1 12AT7 R.F.-2 mixer

1 6AB4 Oscillator

1 6AU6 IF-1

1 6AU6 IF-2

1 6AU6 lF-3/Limiter 1

1 6CS6 IF-4/Limiter2

1 12AT7 Muting/L+R Amplifier

1 6HU6/EM87 Tuning Indicator

1 6D10 FM AUDIO/Left and Right

1st Audio Amplifier

1 6U8 MPX Amplifier and 19KC

Separator/Indicator control

1 12AU7 MPX 38KC Oscillator

1 12AX7 Phono Preamplifier Left

1 12AX7 Phono Preamplifier Right

1 12AX7 Left and Right 2nd Audio Amplifier

1 6U8 Left 3rd Audio Amplifier

1 6U8 Right 3rd Audio Amplifier

2 DiodesDiscriminator

1 DiodeMuting and Tuning Eye Detectors

1 Diode AGC Clamp

4 Diodes Balanced MPX Detectors

2 Diodes Balanced Det. for Indicator Light

2 Silicon Diodes DC Filament Supply

1 MA113 Transistor-Indicator Light Switch

4 Selenium Rectifiers High and Low Voltage Supply

MECHANICAL SPECIFICATIONS

Dimensions

Chassis:  16 inches wide; 57/16 inches high; 13 inches deep including connectors.

Front Panel:  16 inches wide; 57/16 inches high.

Knob Clearance:  1½ inches.

Weight

Chassis: 27½ pounds.

Shipping Weight:  36 pounds.

Finish:  Anodized gold and black (front panel).

Installation Convenient, professional PANLOC.

Dynaco Dynakit Stereo 70

 The Stereo 70 is a dual 35-watt power amplifier, featuring the high quality and moderate price which has characterized earlier Dynakit amplifiers. Its electrical performance is matched only by manufactured amplifiers that cost far more.

The Stereo 70 can be used as apair of 35-watt amplifiers for stereo or as a 70-watt mono amplifier. Its power and distortion ratings are completely conservative. Its listening quality is unsurpassed. 

 Each channel of the Dynakit Stereo70 employs a 7199 triode-pentode and pair of EL-34 output tubes. The lower plate voltage used in the Stereo 70 assures long life for tubes and filter capacitors. In fact this amplifier's components are operated more conservatively than those in any other commercial amplifier we have used.

 The circuitry of the Stereo 70 is very similar to that of the older Mark II and Mark III amplifiers, except for the smaller output transformers. Somehow, the two amplifiers and their power supply have been packaged in a space not much greater than that of the older mono amplifiers, without crowding and apparently without running at a higher temperature.

The Stereo 70's frequency response is so flat that it almost seems pointless to plot it. The power response, in either mono or stereo modes, is nearly as good. The apparent discrepancy between the maximum power outputs shown in these curves and those suggested by the distortion curves is simply due to the different method of measurement. The power response shows the maximum power obtainable before some distortion of the output waveform can be seen on an osciloscope. Very small amounts of distortion can be numerical distortion values can be obtained at much higher power levels.

 The Stereo 70 will develop the eqivalent of 18 watts per channel into a 3-mld capacitive load at 10 kc, which makes it quite suitable for driving electrostatic speakers at high volume levels. It is absolutely stable and free from ringing under and conditions of capacitive loading.

Two power take-off sockets are provided to operate a pair of Dynakit preamplifiers. Each has its own heater winding to prevent interaction between channels.

Specifications

Power Output:  35 watts continuous, 80 watts peak each channel

Frequency Response:  10 to 40,000 Hz ±0,5 dB

Power response:  20 to 20,000 Hz (within 1 dB of 35 watts at less than 1% distortion)

Harmonic Distortion:  immeasurably at power of 10 watts or less

IM Distortion:  less than 1% at 35 watts (less than 0,05% at 1 watt)

Hum an Noise:  Inaudible, better than 90 dB (below 10 watts)

Sensitivity:  1,3 volts RMS input for 35 watts out

Damping Factor:  15

Output Impedance:  4, 8 and 6 Ω

Minimum Channel Separation:  55 dB

Power Consumption:  190 watts 50/60 cps

Preamp provision:  Two power take-offs with independent heater windings to eliminate interaction. Each 6,3 volts 1 amp, 350 volts Dc 10 ma

Special Features: two separate power supply sockets for preamplifier; front panel switch to parallel outputs for operation as a 70 watts monophonic amplifier

Tube Complement:  4 x EL-34; 2 x 7199; 1 x GZ-34/5AR4; selenium rectifier

Dimensions (W x D x H):  13" x 9 ½" x 6 ½"

Weight :  32 pounds

Finish:  chassis and bottom plate bright nickel plated. Cover finished in charcoal brown vinyl paint.

B&W DM 110

 DM110 Stand-mount/Bookshelf loudspeaker system

This Digital Monitor system DM110 was designed and made by B&W, the British manufacturer whose loudspeakers are used by the leading recording companies worldwide to monitor digatl recording sessions.

It is a 2-way system of quite exceptional sensitivity. Other characteristics are broad linear frequency response and excellent transient performance, even at very high sound pressure levels.

 Product Summary

The DM110 is a two-way loudspeaker system acclaimed by reviewers worldwide. Outstanding for its high power handling capacity and super sensitivity.

When Trevor Attwell of Hi-Fi news reviewed the speaker his comments were “a very neutral uncoloured loudspeaker giving excellent imaging some of the best I have yet heard from moving coil systems at the price – and from some far more expensive ones”

 Technical highlights

Refinements in the enclosure give the DM series reduced in lower mid-band coloration and a dramatic improvement in transient response.

Advanced optimisation techniques employing modal analysis of the cabinet structure were a design feature of the enclosure in all four monitors.

Specifications

Drive Units:

HF :  26 mm dome/coil construction of special polymide material

LF :  200 mm nominal piston dia and 26 mm high temperature voice coil with critically impregnated composite short fibre cone

Frequency Response:  70 Hz to 20 kHz ±3 dB

Sensitivity:  89 dB (2.83V, 1m)

Power Handling:  10 W - 75 W

Dimensions (H x W x D):  490 x 260 x 250 mm

Finish:  American Walnut or Black Ash vinyl

B&W DM 220i

 DM220i Stand-mount/Bookshelf loudspeaker system

 This Digital Monitor system DM110 was designed and made by B&W, the British manufacturer whose loudspeakers are used by the leading recording companies worldwide to monitor digatl recording sessions.

It is a 3-way system of quite exceptional sensitivity. Other characteristics are broad linear frequency response and excellent transient performance, even at very high sound pressure levels.

 Product Summary

The total spectrum capability pop, jazz, rock, classical. Features all the distinctive qualities of the smaller models with a third driver extending both frequency response and power handling.

Super sensitive, with high acoustical output yet affordable.

 Technical Highlights

Modal analysis techniques revealed a simple bonding technique of corner joints could improve rigidity and reduce coloration.

New thinking on crossover design has also led to the provision of higher safe power handling and fuse protection overload.

The driver chassis have non-magnetised castings for all the bass midrange units ensuring resonant free high-level sound of the highest amplitude.

Specifications

Drive Units:

HF :  1 x 26 mm high-frequency driver with dome/coil construction of special polymide material

LF :  2 x 200 mm nominal piston dia and 26 mm high temperature voice coil with critically impregnated composite short fibre cone

Frequency Response:  53 Hz to 20 kHz ±3 dB

Sensitivity:  90 dB (2.83V, 1m)

Power Handling:  10 W - 100 W

Dimensions (H x W x D):  680 x 290 x 320 mm

Finish:  American Walnut or Black Ash vinyl

Martin Logan Quest

 Truth can be revealed only through uncomprmised commitment to the highest concepts. The Quest re-creates musical truth through proprietary Electrostatic Loudspeaker technology available only from Martin Logan.  Daring in both form and function, the Quest delivers everything from the most delicate detail to the most inspired crescendo.

Complete Engineering

Only after exhaustive Coputer Aided Design and final listening sessions did our design team put their signature of approval on the Quest interface system.  This high-density composite sub-woofer cabinet provides maximum rigidity and damping to minimize vibration and distortion, resulting in tighter bass. The sub-woofer driver has the strength of "powered" woofers, while blending with the lightning fast performance of our propietary electrostatic transducer technology. Both woofer and midrange control switches are provided to give you additional flexibility to tailor the audio signal to your room environment. Bi-wire capability is provided for those who demend even more purity of sound.

 Superb Components

Within the interface module, a regulated power supply creates stable voltage even under the most extreme conditions. The audio transformer, utilizing high-purity copper and the finest laminates, is vacuum-epoxy dipped for ultimate signal refinement and high voltage protection. All  high-voltage leads are made from the purest copper and coated with teflon. Only superlative materials, including polypropylene capacitors are used throughout.

 Transparent Purity

Weighing a total of less than one cubic inch of air, our thin film diaphragm can change motion as quickly as air itself.  Martin Logan designers have curved the membrane to form a pure thirty-degree dispersion sound field for uncompromised performance without the need for extraneous devices. For the first time in history, pure ESL transparency and resolution can be experienced in a wide dispersion field.

 Complement Your Living Environment

A full selection of standard wood finishes is available to match your decor.

Other finishes may be custom-ordered. Before building any unit, we carefully selected and match all woods by hand. After the wood is fitted to the system, multiple coats of hand-rubbed lacquer are applied.

To accommodate your taste, the Quest is available with any of our grill cloth choices. Both the wood trim and grill cloth options are completely flexible and can be added or changed at any time.

Specifications

System Frequency Response:  28 - 24,000 Hz

Electrostatic Frequency Response:  100 - 24,000 Hz

Woofer Frequency Response:  28 - 2,000 Hz

Woofer Speed:

6,3 ms at 50 Hz (capable of 160 Hz)

1,2 ms at 100 Hz (capable of 830 Hz)

Presence Control Switch:  =2 dB from 1,000 to 5,000 Hz

Bass Control Switch:  -3 dB from 60 - 150 Hz

Crossover Frequency:  125 Hz at 12 dB/octave

Dispersion [Horizontal/Vertical]:  30° /4' Line Source

Sensitivity:  90 dB (1 W/m)

Power Handling:  200 watts per channel RMS

Recommended Amplifier Power:  80 - 200 watts per channel

Nominal Impedance:  8 Ω (minimum 2 Ω)

Phase Angle:  less than 45°

Dimensions (H x W x D):  72 ¾" x 19" x 13"

Weight:  125 lbs

Components:  Custom-wound audio transformers polypropylene bypass caps; 100% OFC coils

Kenwood TK-88

 Solid State FET FM/AM Automatic Multiplex Stereo Receiver

Model TK-88, offers 90 watts music power FM/AM Multiplex Stereo Receiver, brings you the luxury of full, rich-bodied sound and audio perfection of all solid state stereo with FET front-end, silicon transistor amplifier and other advanced engineering features

Special Features

Tuner Section

FET (Field Effect Transistor) 4 gang Tuning Condenser Front-end provides FM 2mV sensitivity and 66 dB image rejection.

5 IF Stages with 4 Limiters and Wide Band Ratio Detector provide 45 dB alternate channel selectivity and freedom from noise and interference.

Automatic FM Stereo/Mono Mode Silent Switching Circuit with Stereo Light Indicator

Interstation Muting Circuit suppresses inter-station noise

4 diodes Time Division Multiplex Decoder for 38 dB stereo separation.

Illuminated Pinpoint FM Tuning Meter

Amplifier Section

90 watt IHF standard total music power to drive even low efficiency Hi-Fi speakers

All Silicon Transistor Amplifier, provides wide 20 to 50,000 Hz frequency response

High Damping Factor for excellent transient response

Very low Im distortion for exceptional, clear low level to high level listening

Blow-out free exclusive, Automatic Circuit Breaker protects Power Transistor (U.S. pat.)

4-sets of Output Speaker terminals (2 sets of stereo speakers) and Front Panel Speaker Selector Switch (A speakers, B speakers, A+B speakers, headphones)

5-position Program Source Selector permits AM, FM Auto, Phono, Tape HD, Aux

3-position Mode Switch for Stereo, reverse, Mono

Direct Tape Monitor Switch for tape monitoring without changing cable connector.

Illuminated Program Source Indicator

Volume control with Rocker Switch for loudness control

Dual Knobs/Bass and Treble controls may be used to regulate each channel separately or simultananeously

High and Low Filters eliminate turntable noise and scratch noise

6 pairs of Input Terminals for Mag, XTAL, Tape HD, Aux, Tape Rec, Tape Play

Front panel Stereo Phone jack

Center Channel Low level Output for monaural amplifier and speaker

Handsome simulated walnut finish cabinet

Specifications

Tuner Section

FM Usable Sensitivity:  2,0 microvolts (IHF)

AM Usable Sensitivity:  10 microvolts

FM Signal-to-Noise Ratio:  60 dB

FM Selectivity (Alt. channel):  45 dB

FM Harmonic Distortion:  0,6%

FM Image Rejection:  66 dB

FM Cross Modulation Rejection:  80 dB

FM Capture Ratio:  2,5 dB

FM Stereo Separation:  38 dB (at 400 Hz)

FM Interstation Muting:  Yes

FM Stereo/Mono Auto Switching:  Yes

FM IF Stages:  5 stages

Amplifier Section

Total Music Power:  90 watts at 4 Ω

IHF Standard:  80 watts at 8 Ω

RMS Power (1 kHz, 0,8% THD):   32/32 watts (at 8 Ω)

IM Distortion (at -3 dB rated output):  0,3%

Frequency Response:  20 - 50,000 Hz (±2 dB)

Power Bandwidth (0,5% THD, -3 dB):  20 - 30,000 Hz

Signal-to-Noise Ratio: 

Aux :  70 dB

Mag :  60 dB

Damping Factor:  46 at 16 Ω;  23 at 8 Ω

Bass Control (at 50 Hz):  ±10 dB

Treble Control (at 10 kHz):  ±10 dB

Input Sensitivity:

Mag :  2 mV

Aux :  150 mV

Tape HD :  2 mV

Dimensions (W x H x D):  16 ½ " x 5' x 12 ¼"

Weight:  24 lbs

Kenwood TK-66

 Solid State FET FM/AM Automatic Multiplex Stereo Receiver

Model TK-66 offers you optimum music power of 60 watts, with FET, front-end, 5 IF stages, silicon transistor amplifier, exclusive power transistor protection circuit (U.S. Pat) and other outstanding features. Truly the most excitingly complete receiver, feature for feature to be found anywhere at this price.

Special Features

Tuner Section

FET (Field Effect Transistor) 4 gang Tuning Condenser Front-end provides FM 2mV sensitivity and 66 dB image rejection.

5 IF Stages with 4 Limiters and Wide Band Ratio Detector provide 45 dB alternate channel selectivity and freedom from noise and interference.

Automatic FM Stereo/Mono Mode Silent Switching Circuit with Stereo Light Indicator

Interstation Muting Circuit suppresses inter-station noise

4 diodes Time Division Multiplex Decoder for 38 dB stereo separation.

Illuminated Pinpoint FM Tuning Meter

Amplifier Section

60 watt IHF standard total music power to drive even low efficiency Hi-Fi speakers

All Silicon Transistor Amplifier, provides wide 20 to 50,000 Hz frequency response

High Damping Factor for excellent transient response

Very low Im distortion for exceptional, clear low level to high level listening

Blow-out free exclusive, Automatic Circuit Breaker protects Power Transistor (U.S. pat.)

4-sets of Output Speaker terminals (2 sets of stereo speakers) and Front Panel Speaker Selector Switch (A speakers, B speakers, A+B speakers, headphones)

5-position Program Source Selector permits AM, FM Auto, Phono, Tape HD, Aux

3-position Mode Switch for Stereo, reverse, Mono

Direct Tape Monitor Switch for tape monitoring without changing cable connector.

Volume control with Rocker Switch for loudness control

Dual Knobs/Bass and Treble controls may be used to regulate each channel separately or simultananeously

High and Low Filters eliminate turntable noise and scratch noise

5 pairs of Input Terminals for Mag, Tape HD, Aux, Tape Rec, Tape Play

Front panel Stereo Phone jack

Center Channel Low level Output for monaural amplifier and speaker

Handsome simulated walnut finish cabinet

Specifications

Tuner Section

FM Usable Sensitivity:  2,0 microvolts (IHF)

AM Usable Sensitivity:  10 microvolts

FM Signal-to-Noise Ratio:  60 dB

FM Selectivity (Alt. channel):  45 dB

FM Harmonic Distortion:  0,6%

FM Image Rejection:  66 dB

FM Cross Modulation Rejection:  80 dB

FM Capture Ratio:  2,5 dB

FM Stereo Separation:  38 dB (at 400 Hz)

FM Interstation Muting:  Yes

FM Stereo/Mono Auto Switching:  Yes

FM IF Stages:  5 stages

Amplifier Section

Total Music Power:  60 watts at 4 Ω

IHF Standard:  50 watts at 8 Ω

RMS Power (1 kHz, 0,8% THD):   20/20 watts (at 8 Ω)

IM Distortion (at -3 dB rated output):  0,3%

Frequency Response:  20 - 50,000 Hz (±2 dB)

Power Bandwidth (0,5% THD, -3 dB):  20 - 30,000 Hz

Signal-to-Noise Ratio: 

Aux :  70 dB

Mag :  60 dB

Damping Factor:  46 at 16 Ω;  23 at 8 Ω

Bass Control (at 50 Hz):  ±10 dB

Treble Control (at 10 kHz):  ±10 dB

Input Sensitivity:

Mag :  2 mV

Aux :  150 mV

Tape HD :  2 mV

Dimensions (W x H x D):  16 ½ " x 5' x 12"

Weight:  23 lbs

Kenwood TK-55

 Solid State FM-Multiplex Stereo Receiver

Model TK-55, 60 watts music power Fm Stereo Receiver with silicon transistor amplifier, kenwood's precision engineered component encompassing the fine detailing of quality craftsmanship at a surprisingly modest price.

Special Features Tuner Section

4-gang Tuning Condenser All Transistor Front-end , provides superior sensitivity.

5-IF Stages with 4 Limiters and Wide-band Ratio Detector, provide 45 dB alternate channel selectivity and freedom from noise and interference.

Automatic FM Stereo/Mono Mode Silent Switching Circuit with Stereo Light Indicator.

4 diodes Time Division Multiplex Decoder for 38 dB stereo separation.

Illuminated Pinpoint FM Tuning Meter

Special Features Amplifier Section

60 watt IHF standard total music power

All Silicon Transistor Amplifier, provides wide 20 to 50,000 Hz frequency response and 20 to 20,000 Hz power bandwidth

High Damping Factor

Very low Im distortion for exceptional, clear low level to high level listening

Blow-out free exclusive, Automatic Circuit Breaker protects Power Transistor (U.S. pat.)

3-position Program Source Selector permits FM Auto, Phono, Aux

Direct Tape Monitor Switch for tape monitoring without changing cable connector.

Mode switch for Stereo and Mono listening

Volume control with Rocker Switch for loudness control

Bass and treble controls may be used to regulate each channel simultaneously

4 pairs of Input Terminals for Mag, Aux, Tape Rec, Tape Play

Front panel Stereo Phone jack

Center channel Low Level Output for monaural amplifier and speaker.

Noise Filter Switch inserts a filter into the circuit and effectively reduces the high-frequency noise

4-sets of Output Speaker Terminals (2 sets of stereo speakers) and Front Panel Speaker Selector Switch (A speakers, B speakers, A+B speakers, headphones)

Handsome simulated walnut finish cabinet

Specifications

Tuner Section

FM Usable Sensitivity:  2,5 microvolts (IHF)

FM Signal-to-Noise Ratio:  60 dB

FM Selectivity (Alt. channel):  45 dB

FM Harmonic Distortion:  0,6%

FM Image Rejection:  60 dB

FM Cross Modulation Rejection:  80 dB

FM Capture Ratio:  2,5 dB

FM Stereo Separation:  38 dB (at 400 Hz)

FM Interstation Muting:  No

FM Stereo/Mono Auto Switching:  Yes

FM IF Stages:  5 stages

Amplifier Section

Total Music Power:  60 watts at 4 Ω

IHF Standard:  50 watts at 8 Ω

RMS Power (1 kHz, 0,8% THD):   20/20 watts (at 8 Ω)

IM Distortion (at -3 dB rated output):  0,3%

Frequency Response:  20 - 50,000 Hz (±2 dB)

Power Bandwidth (0,5% THD, -3 dB):  20 - 30,000 Hz

Signal-to-Noise Ratio: 

Aux :  70 dB

Mag :  60 dB

Damping Factor:  46 at 16 Ω;  23 at 8 Ω

Bass Control (at 50 Hz):  ±10 dB

Treble Control (at 10 kHz):  ±10 dB

Input Sensitivity:

Mag :  2 mV

Aux :  150 mV

Tape :  2 mV

Dimensions (W x H x D):  16 ½ " x 5' x 12 ¼"

Weight:  20 lbs

Harman/Kardon A402

 Amplifier-Preamplifier Harman/Kardon model A402 is a component of high fidelity audio system. The desig and manufacture of this unit we offer uncompromised reproduction of the music for your enjoy.

This component is equipped on  special display sensitivity.  Is comprised of a light-emitting diode display and four pushbutton switches that select mode of operation. The LED display is a faster, more responsive and, therefore, more accurate indication of dynamic range and power level.  The ranges for the display are established by pushbutton switches 1 and 2 under the display. Once the range is established the dB level of the signal below full scale is indicated by the calibration on the LED panel.

Features

Completely sseparate power supply for each channel

Light emiting dioda (LED) output display

Double-lighted tone controls

Tape dubbing with isolated circuity

Two low-level and five high-level inputs

Wideband design with exceptional square wave response and phase lineality.

 The A402's unusual LEDoutput display, program control capability and complete tape handing features make it an extremely attractive value. But it is the transparent, detailed quality of its musical reproductionthat sets the A402 truly apart from conventional amplifiers.

Its exceptional performance results from designing for square wave response, phase linearity and extremely wide frequency bandwidth. The importance of this design concept is briefly explained in the section entitled:

Square Waves - Wideband Design and Amplifier Performance

Most amplifier are designed and tested with sine waves (single frequencies). These tests are useful for measuring certain kinds of distortion and we use them too. But sine waves are too simple to represent the difficult domands that musical signals make on amplifiers.

The square wave, composed of many frequencies (a fundamental and its odd-order harmonics), presents an amplifier with the same kind of complex load as musical sound. Ther is a direct and audible correlation between the quality of an amplifier's square wave response and the quality of its musical reproduction. Since a square wave represents many frequencies (10 times above the fundamental), an extremely wide frequency bandwidth is necessary in order to achieve really good square wave response. Precise square wave configuration also indicates excellent phase linearity. This ensures that at the depth and ambience of the original music will be preserved.

All Harman Kardon electronic components are designed for optimum square wave response, wide frequency bandwidth and phase linearity.

 The A402's LED power output display, much faster and more accurate than meters, gives a continuous, precise and easy-to-read monitor of the output. The display has two sensitivity ranges. The first position reads full scale at 40 watts (full output). The second control gives full scale readout at 6 watts.

Great flexibility in shaping program material is provided by hinged tone controls. The bass control provides 12 dB boost or cut at 200 Hz or 400 Hz. The treble control provides 12 dB boost or cut at either 5 kHz or 10 kHz. The high and low frequency filters have steep slopes which permit elimination of disturbing hiss or rumble without affecting program material.

The A402 provides complete monitoring facilities for two tape recorders. In addition, you can copy tapes from one machine to another while simultaneously listening to a third, separate program source by using the A402's special isolated tape dubbing circuitry.

 Except for absolute power, the A402 amplifier is the technical egual  of separate components that cost considerably more. And there are few components indeed that are its sonic equal.the A402 incorporates the latest refinement of the twin-power design Harman Kardon developed in 1959 for the Citation One amplifier. A design whose significant advantages are now influencing the thinking of other component manufactures. The A402 is driven by two complete, discrete separate power supplies, one for each channel. Even when music is extraordinarly dynamic, and the domands made on the amplifier are very great, the energy drawn by one channel will in no wayaffect the other. Twin power ensures excellent transient response and freedom from the overload distortion that can mask musical reproduction.

Specifications

Power Output:  40 watts Minimum RMS per channel (both channels driven into 8 Ω, from 20-20,000 Hz,0,1% THD)

Power Bandwidth:  from 10 Hz to 60,000 Hz with less than 0,1% THD (both channels driven simultaneously into 8 Ω, at 20 watts per channel)

Frequency Response:

Less than 4 Hz to 160,000 Hz -3,0 dB

Less than 4 Hz to 100,000 Hz -1,0 dB

Square Wave Rise Time:

Less than 1,5 microseconds (power amplifier only

Less than 2,0 microseconds (system)

Square Wave Tilt:  Less than 5% at 20 Hz

Total Harmonic Distortion:  Less than 0,1% from 250 milliwatts to 40 watts RMS (both channels driven simultaneously into 8 Ω, 20-20,000 Hz)

Intermodulation Distortion: 

Less than 0,08% at 40 watts (SMPTE measurement)

Less than 0,04% at 1 watt (SMPTE measurement)

Damping Factor:  Greater than 50

Hum and Noise:

Power Amplifier Only :  greater than 100 dB

Tuner, Aux, Tape Monitor Input :  greater than 77 dB

Phono Input :  greater than 69 dB

Input Impedance:

Power Amplifier :  greater than 33 k Ω

Tuner, Aux, Tape Monitor :  greater than 33 k Ω

Phono :  47 k Ω

Input Sensitivity:

Power Amplifier Only :  1,2 volts RMS (rated power output)

Tuner, Aux, Tape Monitor :  125 millivolts (rated power output)

Phono :  2,2 millivolts (rated power output)

Overload:  90 millivolts input (Phono preamplifier)

Preamplifier Harmonic Distortion:

Tuner, Aux, Tape Monitor :  0,018%

Phono :  0,055%

RIAA Equalization:  ±1,0 dB

Preamp Output Impedance:  less than 600 Ω

Tone Control Effect:

Bass Hinge at 200 Hz :  ±3 dB at 200 Hz;  ±9 dB at 60 Hz

Bass Hinge at 400 Hz :  ±3 dB at 400 Hz;  ±9 dB at 120 Hz

Treble Hinge at 5 kHz :  ±3 dB at 5 kHz;  ±9 dB at 14 kHz

Treble Hinge at 10 kHz :  ±3 dB at 10 kHz;  ±9 dB at 28 kHz

Contour Effect:  +10 dB at 50 Hz;  +3,5 dB at 10 kh at -40 dB attenuation

Filter Effect: 

High Cut :  -3 dB at 3500 Hz  6 dB/octave

Low Cut :  -3 dB at 65 Hz  12 dB/octave

Dimensions (W x H x D):  394 x 134 x 375 mm (15 ½" x 5 ¼" x 14 ¾")

Weight:  11,0 kg (24 lb 2 oz)