What is stereo?

There are now two system of high fidelity, monophonic (monaural) and stereophonic. Monophonic is a system that starts from one microphone and is fed through a single high fidelity set. Stereophonic is a double system. Two separate microphones are placed at different sides of the orchestra and two different systems are used to keep the two signals or channels separated. Two separate speakers are used, placed on different sides of you room. Stereo is much like 3-D photography, two slightly different sound reach your ears giving you a new dimension in sound.

H.H. Scott '59

Chario Silhouette 100 Tower

The Silhouette series of loudspeakers succeeds the renowned Syntar Loudspeakers that for sixteen years were widely recognized for their excellence. With improved drivers, superior cabinetry and modernized esthetics, these speakers represent a reference “best buy”. The major advantage in using the Silhouette loudspeakers is their extreme flexibility and accurate music reproduction even in acoustic environments that are not ideally suited for this purpose.
Ha raccolto il testimone della storica serie Syntar che per sedici anni ha mietuto successi in tutto il mondo. Rinnovati gli altoparlanti, rinnovato il cabinet, rinnovata l’estetica ma lasciati inalterati i principi costruttivi e di progetto che hanno fatto di quella serie il “Best Buy” di riferimento. Peculiarità indiscussa della Serie Silhouette è la grande duttilità, che consente il raggiungimento di una equilibrata riproduzione in qualsiasi tipo di ambiente, anche i meno adatti sotto il profilo acustico

Low Frequency Load: Vented 2π sr NRS
Configuration: 3 Way floor standing
1 Tweeter 26mm soft dome
1 Midrange 130mm Polymeric Compound
1 Woofer 130mm Polymeric Compound
Sensitivity: 88dB SPL normalized to 1m with 2.83 Vrms
pink noise within IEC 268-13 compliant listening room
Low Frequency Cut Off: 60Hz @ -3dB referred to C4 WETS
Rated Impedance: 4 Ω
Suggested Amplifier: Rated for 100 W / 4 Ω max Average Power
XOver Frequencies: 260 / 1600 Hz
Size (HxWxD): 880x165x290 mm
Weight: 15 Kg
Cabinet Finish: HDF Wood

Chario Silhouette 100

The Silhouette series of loudspeakers succeeds the renowned Syntar Loudspeakers that for sixteen years were widely recognized for their excellence. With improved drivers, superior cabinetry and modernized esthetics, these speakers represent a reference “best buy”. The major advantage in using the Silhouette loudspeakers is their extreme flexibility and accurate music reproduction even in acoustic environments that are not ideally suited for this purpose

Ha raccolto il testimone della storica serie Syntar che per sedici anni ha mietuto successi in tutto il mondo. Rinnovati gli altoparlanti, rinnovato il cabinet, rinnovata l’estetica ma lasciati inalterati i principi costruttivi e di progetto che hanno fatto di quella serie il “Best Buy” di riferimento. Peculiarità indiscussa della Serie Silhouette è la grande duttilità, che consente il raggiungimento di una equilibrata riproduzione in qualsiasi tipo di ambiente, anche i meno adatti sotto il profilo acustico.

Low Frequency Load: Vented NRS
Configuration: 2 Way
1 Tweeter 26mm soft dome
1 Woofer 130mm Polymeric Compound
Sensitivity: 87dB SPL normalized to 1m with 2.83 Vrms
pink noise within IEC 268-13 compliant listening room
Low Frequency Cut Off: 70Hz @ -3dB referred to C4 WETS
Rated Impedance: 8 Ω
Suggested Amplifier: Rated for 80 W / 8 Ω max Average Power
XOver Frequency: 1650 Hz
Size (HxWxD): 340x165x290 mm
Weight: 7 Kg
Cabinet Finish: HDF Wood
Optional Stand
Weight: 6kg
Size (HxWxD): 630x260x310 mm
Natural wood veneered HD

McIntosh MA 6400

McIntosh has been manufacturing Integrated Amplifiers since 1963, with the current models representing the fifth generation of this popular combination design. The same design concepts and performance innovations that McIntosh has developed for their separate components have been incorporated into these combinations models.

The preamplifier sections reproduce traditional stereo audio with unsurpassed sonic accuracy without sacrificing control flexibility. Tone controls and loudness compensation are active circuits which provide precise adjustment and when set in the flat position, are electrically neutral and have no effect upon the signal. Flexibility is enhanced through full function remote control and traditional McIntosh ease of use is demonstrated by the layout and function of the controls.

The power amplifier section are identical in design to those of separate mcIntosh amplifiers, offering the same performance and traditional McIntosh design integrity. Both models provide illuminated power level wattmeters, which indicate the true power output delivered to the speakers, as well as other innovative circuit designs that together contribute to the legendary McIntosh sound.


Power Output: 100 watts at 4 ohm

Frequency Response: 20 – 20,000 Hz, +0, -0,5 dB

Total Harmonic Distortion: 0,005%

IM Distortion: 0,005%

IHF Dynamic Headroom: 4 ohms, 2.4 dB

Damping Factor: 40 at 4 ohm

Output Indicator: Meters

Output Interface: Direct Coupled

Pre Section


Phono: 2,5 mV rated output (0,5 mV IHF)

High Level: 250 mV reted output (50 mV ihf)

Power Amp IN: 2,5 mV rated output

Signal-to-Noise Ratio:

Phono: 90 dB, below 10 mV input, (84 dB IHF)

High Level; 100 dB below rated output (91 dB IHF)

Max. Input Signal

Phono: 90 mV

High Level: 10 V

Bass/Treble Control: variable 12 dB boost to 12 dB

Inputs: 7 high level

Input Impedance:

Phono: 47 kohms and 65 pF Capacitance

High Level: 22 kohms

Phono: Dual Aux/MM Phono


Switching for 2 speakers;

Signal Processor loop;

2 tape Monitor switches.

Dimensions (W x H x D): 445 x 137 x 508 mm (17-1/2 x 5-3/8 x 20 in)

Weight (Net): 18,6 kg (41 lbs)

B&W DM110i

The DM110i is a 2-way vented box stand-mount/bookshelf system with high power handling capacity. 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.


Drive Units:

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

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

Frequency Response: 70 – 20,000 Hz, ±3 dB

Sensitivity: 90 dB (2.83V/1m)

Power Handling: 10W – 75W

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

Finish: American Walnut or Black Ash vinyl

JBL L-222 (1980)

The JBL L222 loudspeakers systems offers extended frequency response, great dynamic range, outstanding musical detail, and exceptionally good stereo imaging.

Innovative and advanced engineering gives the L222 its exciting sound. JBL engineers created a design that aligns the acoustic centers of the individual loudspeaker elements while retaining the ideal flat baffle panel. Thus, all frequencies maintain the same time relationship to each other as they had when they were recorded, giving music the "presence" and immediacy of a live performance.

The combination of a 355 mm (14 ") woofer and large passive rediator gives the L222 awesome, deep bass. The specific tuning of the passive rediator adds warmth and presence to the mid-bass region, producing a dramatic and powerful effect at high volumes and an exceptionally pleasing sound, retaining full musical detail, at low listening levels.

Bold Visual Style

A tall, slim wedge the enclosure is a product of the JBL tradition of fine craftsmanship and attention to detail, a tradition extending back to the origins of the audio industry.

The L222 appears almost two dimensional an exciting presence, yet not visually overpowering. Its columnar array places the transducers, as nearly as possible at ear level, where they perform to fullest advantage. At the same time, the amount of floor space required is minimal.

Made of extensively braced 19 mm (¾") compressed wood (acoustically superior to solid wood) the enclosure features a veneer of American black walnut, hand rubbed with an oil/wax preparation to a lustrus finish.

Power Capacity

JBL products are unique in combining high efficiency with high power capacity. The L222 produces sound at comfortable listening levels when driven by as little as 10 watts continuous sine wave, but for the best performance we recommend a more powerful amplifier. The L222 can be used with amplifiers rated up to 400 watts continuous sine wave per channel.

Specifications Loudspeaker:

Low-Frequency :

Nominal Diameter: 355 mm (14")

Voice Coil: 100 mm (4") copper

Magnetic Assembly Weight: 8,5 kg (18 lb)

Flux Density: 1,2 tesla (12,000 gauss)

Sensitivity: 91 dB (1W/1m)


Nominal Diameter: 125 mm (5")

Voice Coil: 22 mm (") copper

Magnetic Assembly Weight: 0,74 kg (1 lb)

Flux Density: 1,35 tesla (13,500 gauss)

Sensitivity: 93 dB (1W/1m)

High Frequency Ring Radiator:

Horn Mouth: 64 x 32 mm (2½" x 1¼")

Dispersion: 90° horizontal, 45° vertical at 12 kHz

Magnetic Assemby Weight: 1,5 kg (3¼ lb)

Flux Density: 1,65 tesla (16,500 gauss)

Sensitivity: 105 dB (1W/1m)


Max. Recommended Power: 400 watts per channel

Nominal Impedance: 8Ω

Crossover Frequencies: 800 Hz, 5 kHz

System Sensitivity: 90 dB SPL (1W/1m)


Finish: Oiled walnut

Grille Color: Black

Dimensions (W x H x D): 1225 x 512 x 390 mm (48¼" x 20" x 15")

Weight (Net): 51 kg (112 lb)

Marantz Esotec PM-4 (1980)

The Integrated Amplifier which can switch a pure Class-A and AB class.

In addition to pure Class-A 15 W/ch, the change of AB class 60 W/ch is attained. And in order to raise the quality of AB class even to the level of a pure Class-A, the high speed high fT transistor which took high high region cut-off frequency with 90MHz is adopted as the power stage. Switching distortion which is a fault of AB class is banished to a limit.

Good dual FET of the pair property was adopted as the input stage of a power amplifier part, and the property failure by an impedance variation is prevented with the source follower stream composition. Moreover, both a Class-A and AB class can be enjoyed by switching the bias current of an output stage. A super high ft transistor with a cut-off frequency of 90 MHz is adopted as a power element, and switching distortion is suppressed to the relative minimum.

Marantz PM-4 Esotec Series, Integrated Amplifier

Class: A-B Sine Power:

Class A: 15 W + 15 W (8Ω),

Class A-B: 60 W + 60 W (8Ω)

THD: 0,015% (20Hz - 20kHz at the time of an 8Ω load intensity and an Output power)

Cross modulation distortion (60Hz:7kHz=4:1): 0.015% (at the time of an 8Ω load intensity and an Output power)

Dumping factor (an 8Ω load intensity, 1kHz): 70

Transmission range: 5 - 100,000 Hz +0 -2 dB

Frequency response: 20 - 20,000 Hz -0, 3 dB

Distortion: 0.015%

Tone control:

Bass: ±10dB (100Hz)

Treble: ±10dB (10kHz)

Input sensitivity/impedance:

Phono 1, 2 MM: 2.5 mV/47 kΩ

Phono 2 MC: 2 00 mV/100Ω

AUX, tuners, tape 1, 2: 150 mV 25 kΩ

RIAA phono: 20 - 20,000 Hz, ±0.25 dB

Signal-to-Noise ratio:

Phono MM: 84 dB

Phono MC: 64 dB

AUX, tuners, tape: 104 dB

Phono max. Input: 330mV (MM); 25 mV (MC) at 1kHz

Inputs: 2 x phono, switchable phono 1: MM + MC, Phono 2: MM, 2 x tape

Outputs: 2 x speaker, headphones

Voltage: 110/120/220 V AC, 60/60 Hz

Power consumption: 150 watts

Dimensions (W x H x D): 416 x 117 x 334 mm

Weight: 9.5 kg

AIWA AD-A70 (1986)

Two of the most versatile auto reverse decks on the market still wouldn't give you the multifunction operation possibilities available from just one of AIWA's new Auto Sorting double cassette decks. Totally in class by itself, the exciting new AD-A70 pffers quic reverse recording and playback in BOTH decks to allow a wide variety of automatic, microprocessor controlled operations like normal or double speed dubbing from up to 5 cassettes to 1 and random programmable playback from up to 5 cassettes. It's a fact: no other deck available gives you this much convenience and versatility.

What's Auto Sorting?

The answer can be found in Deck I. Inside there's an entirely new system that holds up to 5 cassettes in a special cassettee block. Following the commands input with the front-panel controls, the mechanism actually "sorts" the tapes for random programmed playback and sequential timed recording.


Quick Reverse Recording and Playback

15 Selection Random Programmed Playback

Sequential Playback of 5 Tapes

Automatic Programmed Synchro-Dubbing; Normal or High-Speed

Continous Timed Recording of up to 5 Cassettes (Deck I)


AIWA's flat keyboard operation panel with feather-touch full IC logic controls.

Dolby B and C noise reduction system

Electronic Tape counter

Blank skip

Auto/manual Rec-mute

Auto tape selector (Metal/CrO₂/Normal)

Music Sensor (Deck II)


Track: 4-track, 2-channel

Tape Speed: 4,8 cm/sec. (1-7/8 lps)

Frequency Response (-20 VU):

Normal: 20 - 14,000 Hz; 30 - 13,000 Hz

CrO₂: 20 - 15,000 Hz; 30 - 14,000 Hz

Metal: 20 - 16,000 Hz; 30 - 15,000 Hz

S/N Ratio: 78 dB (Dolby C, Metal)

Wow and Flutter: 0,06%

Forward and Rewind Time: 90 sec

Head: REC/PB: DX Head x 2; Erase: Double-gap Ferrite Head x 2

Motors: DC servo motor x 2 DC motor for Auto Sorting mechanism x 2

Input Sensitivity/Impedance: 50 mV/47kΩ

Output Level Impedance:

Line Out: 0,38 V/47 kΩ

Headphone: 0,5 mW/8Ω

Power Source: AC 120/220/240 V, 50/60 Hz

Dimensions (W x H x D): 330 x 107 x 348 mm (13" x 4¼" x 13")

Weight: 6,0 kg (13,2 lbs)

Sansui LM-110 (1976)

Sansui has again challenged traditional thinking in speaker system design. And again the results mean spectacular improvements in reproduced sound under actual listening conditions in your home. The new LM Series represents not just a revolution in design but a re-evaluation of high fidelity reproduction standards as well. Another great step in the realistic world of musical sound.
The unique multi-radiation baffle for the LM (Linear Motion) tweeter driver utilizes back radiated sound energy to enhance the overall sense of perspective sound image resolution and location in actual stereo application. It features three exponential horns to channel some of the out-of-phase backradiated sounds of the tweeter into the listening field. Essentially this unusual design emphasizes certain phase difference relationships in multi-channel music to give us a greater sense of stereo perspective. The fact that the separately-baffled LM tweeter driver has very free movement against input signals means better transient response too much better.
The proof of these improvements is yours to enjoy in three LM models. LM-110 (35 watts peak),LM-220 (45 watts peak) and LM-330 (60 watts peak).

The LM Tweeter itself is a Sansui-exclusive Linear Motion Driver with a CCAW (Copper-Clad Aluminum Wire) voice coil to reduce moving mass and help improve transient response. The diaphragm features a steeply convex phase equalizer to eliminate phase interference inside the cone for better high-end response.

Since the LM Tweeter is mounted on a separate baffle, as explained below, it requires no back cap or cavity to block out the strong and potentially damaging high pressure waves created by the woofer in the enclosure. The die-cast aluminium frame on the tweeter itself is ported to correspond to the three openings in the multi-radiation baffle, and the tweeter diaphragm is free to move to and fro in linear response to input signals with fast rise time. The result is free Linear Motion in the air on in technical terms, better transient response. The pure sounds of the LM Tweeter prove the advantages over the blurred and muddy effects of less transient types at first hearing.

The low-frequency driver in the LM has a number of unusually advanced features for mor natural bass respons, making it the perfect mate for the improved LM Tweeter system.
The superlight woofer cone is formed by a special non-press molding process and features a unique multi-corrugation design to achieve for proper stiffness and internal loss to create a living bass tone. To suspend this cone without defeating its best qualities. Sansui engineers designed an accordion-crease surround itself of appropriate stiffness and acoustical properties. The concave equalizer in the throat of the cone is still another new Sansui design and it serves perfectly to improve response near the crossover frequency. Finally, the LM woofer features a particularly strong magnetic circuit and voice coil, further extending the unit's ability to respond with linear motion to even extremely high level input signals with proper damping for improved linearity.

Woofer: 165 mm (6½") Cone Type
Tweeter: 65 mm (2 ⁹/₁₆") Cone Type
Power Rating: 35 watts (peak)
Impedance: 8 ohms
Sensitivity: 90 dB/W (New JIS 1 m)
Frequency Range: 38 to 20,000 Hz
Crossover Network: 2-way 12 dB/oct L-C Parallel Type
Crossover Frequency: 2,000 Hz
Finish: Simulated wood grain
Dimensions (W x H x D): 248 x 534 x 194 mm (9-13/16 x 21-1/16 x 7-11/16 inches)
Weight: 8,1 kg (17,9 lbs) net, 18,2 kg (40,1 lbs) packed

Kenwood KA-3700 (1977)

KA-3700 Integrated Stereo Amplifier

The lowest distortion of any amplifier in its class and full power down to 20 Hz. Overal performance you would expect in a much higher priced amplifier.


20 watts per channel, min. RMS both channels driven at 8 ohms, 20 Hz to 20 kHz, with no more than 0,08% THD.

Oversize capacitors and high-output power transistors.

Power stability with a direct-coupled complementary differential amplifier.

Low-noise, direct coupled phono equalizer (78 dB).

Clik-stop tone controls.

Low boost loudnest control for realistic listening at low and medium volume.

Oversize Volume and Selector controls.

tape monitoring.

Optional CB-3 walnut veneer cabinet, B-5 walnut veneer side panels, or D-5 carrying handles available.


Power Amplifier Section

Power Output: 2 x 20 W, at 8Ω, 20 Hz - 20 kHz

Dynamic Power Output: 100 watts 4Ω

Total Harmonic Distortion: 0.08% at rated power into 8Ω

Intermodulation Distortion: 0.04% at rated power into 8Ω

Power Bandwidth: 10 Hz at 50 kHz

Damping Factor: 30 at 8Ω

Speaker impedance: 4Ω to 16Ω

Preamplifier Section

Input Sensitivity/Impedance:

Phono : 2.5 mV/50 kΩ

Tuner: 150 mV/10 kΩ

Tape , Aux: 150 mV/50 kΩ

Signal to Noise Ratio:

Phono : 72 dB (for 2,5 mV input); 78 dB (for 5,0 mV input); 84 dB (for 10 mV input)

Tuner, AUX, Tape : 100 dB for 150 mV input

Maximum Input Level Phono: 150 mV (at 1 kHz, 0,8% THD)

Frequency Response:

Phono: RIAA standard curve ±0,4 dB

AUX, Tape: 20 Hz to 20 kHz ±1 dB

Tone Control

Bass: ±7,5 dB at 100 Hz

Treble: ±7,5 dB at 10 kHz

Loudness Control: 9 dB at 100 Hz (at -30 dB Volume level)


Power Requirements: 120/240 V, 50/60 Hz

Power Consumption: 185 watts

Dimensions (W x H x D): 380 x 140 x297 mm (14-31/32" x 5-1/2" x 11-11/16")

Weight: 5,8 kg (12,7 lbs) Net

Spectral Audio DMC-20

The spectral DMC-20 is a true dual monaural reference preamplifier which incorporates a long list of technical innovations and enhancements to achieve new heights of signal linearity and speed of signal response. The result is stunning musical coherence and transparency. A tour through the DMC-20's outstanding features will serve to highlight its remarkable capabilities.

Volume. The DMC-20's volume control is a custom made, conductive plastic, precision stepped attenuator built to Spectral's design. Our extensive comparative testing confirms that this device, with its satisfying torque feel, offers by far the most sonically transparent operation, precise tracking (channels within .10 decibel) and extended life of any volume attenuator made today.

Balance. Spectral takes the most uncompromising approach to balance control, utilizing a precision stepped attenuator with 14 settings employing metal film resistors. The DMC-20's balance control features a center position bypass - in this position the control is out of the circuit altogether.

Input selector. The input selector is not in the signal path, but controls the relay logic system which switches between source inputs at optimal positions in the circuit. This sealed, mil-spec rotary switch features highest-grade heavy plated gold over coin silver contacts for extended durability and reliability.

Internal Controls:

Input Trim 20 dB range for tuner, disc, aux 1, aux 2, tape

Input Trim Bypass Switches

Phono Input Impedance selector (opt.)

Protection System bypass switch

Balanced Input Level 20 dB range

Tape output level

Balanced High Level operation switch

Rear Panel Connectors:

Signal Ground post (gold)

5 RCA Input connector sets (gold)

Balanced Input Neutrik XLR connectors for aux 3 (gold)

Tape input and output RCA connector set (gold)

Balanced output RCA connectors for non-inverting, inverting

Balanced output Neutrik XLR connectors (gold)

DC Power Hi-Rel input connector

One look at the DMS-20 confirms the boldness and meticulous attention to detail with which Spectral engineered this ground-breaking preamplifier power supply. Using cascaded power supplies, individually regulated for each rail of each channel, the DMS-20 delivers flawlessly clean and well-regulated DC power to the DMC-20, completely isolated from ground currents and decoupled from high frequency interference. With a total output of 80 volts, rare for a solid state device, the DMS-20 has the reserves of a 100-watt-per-channel power amplifier.
It is Spectral's growing conviction that analog circuits, although conceptualized in two dimensions, should be realized so as to take full advantage of all three physical dimensions for ultimate performance. In the DMC-20 the power and ground conductors, and housekeeping functions such as ferrying control signals from the front panel to the relay system, are carried on a slide-out "mother board." The amplifier modules for line stage amplification and optional phono stage and balanced input conversion, are located on their own smaller PC boards which float above the mother board. Power and ground connections are made by "popping up" the relevant conductors at the precise points where they are needed in each circuit. And fully 90% of the signal path is carried on specially designed, phase-aligned, individually terminated MIT/Spectral cabling which acts as the preamplifier's signal bus. With the DMC-20, Spectral for the first time carries the audiophile cable concept which it pioneered with MIT into the active heart of the amplifier circuit.
This three-tiered architecture offers the most innovative and uncompromising response to the classic preamplifier challenge to reduce the contamination of sensitive, low level music signals by extraneous noise to an absolute minimum. Power, ground and signal conductors no longer snake around one another on two dimensional printed circuit boards with their inherently imperfect dielectrics.
Spectral's polysulfone (Teflon derived) printed circuit boards, custom made for us by Tektronix, have no rival in the audio field. But the low level music signal's extreme sensitivity to radiant energy fields makes it imperative, we believe, to remove it from the crowded domain of the PC board at every opportunity.
The signal bus is routed in bundles to prevent interference from radiated fields, and interconnections are made at a 90 degree angle to eliminate crosstalk between channels. Intricate and costly, this approach is a challenge to engineers and craftspeople alike. But we think the resulting sonic purity and impeccable transparency make any other approach unthinkable for a state-of-the-art instrument like the DMC-20.

Specifications DMC-20

Input Compliment: 7 Inputs - tuner, disc, aux 1, aux 2, aux 3, (balanced, phono) optional

Output Compliment: 4 ouputs - normal, inverted, balanced, tape

Control Compliment

Output Attenuation: 32 step conductive plastic, modified log taper

Output Balance: 15 step attenuator switch with center position bypass

Mute Switch: 0 - 20 dB attenuation

High Level Trim: 0 to 10 dB attenuation for each channel all high level inputs, with attenuation bypass switches.

Mode Switches: Stereo/mono, absolute phase

Input Selections: 6 plus tape monitor

Recording Amplifiers

Protection Circuit

Protection Mode: DC Offset, oscillation

Method: Crowbar output relays

Sensitivity: 20 mV continuous DC

Recovery: Approx. 10 seconds

Chassis Temperature: Internal 48° C @ 25° room temp.

Model 201 Balanced Output Module

Fully Balanced Operation: All D.C. coupled

Frequency Response (any level to 36 V RMS):

DC to 4 MHz, -3 dB

DC to 2.5 MHz, -0.10 dB

Slew Rate: 1000 V/us or greater

Rise Time: 70 nanoseconds

Distortion: Less than 0.01% THD and IM

Crosstalk: Greater than 90 dB

Noise: 105 dB A Weighted, ref 100 mV @ 1 KHz

Output Voltage: 1.6 VRMS, 100V P-P max.

Output Current: 1 Amp max. per channel, balanced out

Gain: 40 dB unbalanced, 34 dB balanced

DMS-20 Power Supply Technical Data

Output Voltages:

1) Dual ± 40 VDC @ 0.6A

2) Dual ± 40 VDC @ 0.6A

3) Single ± 5 VDC @ 1A

4) Single ± 10 VDC @ 1A

Noise and Ripple: Less than 200 mV peak to peak

Reserve Capacity: 180 Joules per supply (±40 VAC)

Input Mains Voltage: 100, 120, 220 V AC ±10% @ 47.5 Hz to 440 Hz (factory set)

Power Consumption: 80 watts normal, 175 watts max.

Protection: Short circuit, over voltage, line transient protected

DMC-20 Preamplifier Mechanical

Weight: 5,25 kg (12 lbs)

Dimensions (W x H x D): 483 x 635 x 317 mm (19" x 2½" x 12½")

DMS-20 Power Supply Mechanical

Weight: 49 kg (22 lbs)

Dimensions (W x H x D): 483 x 635 x 318 mm (19" x 2½" x 12½")

Luxman L-560 (1986)

Many Class 'A' amps use so-called quasi-Class 'A' configuration regardless of their remarks and namings, which are totally different from our genuine Class 'A'. With the bias current fixed, the signals are amplified without switching, thus producing none of crossover and notch distortions associated with the quasi-Class 'A' amps, assuring absolute stability even into low-impedance loads. And unprecedented generous 50W per channel taken out at the cost of lavish structure equalling that for 250W/ch in quasi-Class 'A' or Class 'AB' operation, reproduces all the subtleties of music even at a low listening level to say nothing of an overwhelming dynamism at a high volume.

Large Smoothing Capacitors
The giant power supply section features toroidal transformer and newly developed pure-focus capacitors, which eliminates leakage of flux, to reproduce the subline sound image with steadfast core and an explosive volume feeling at the bas range.
9-Point Turnover Frequencies for Tone Controls
Emphasis is placed on the frequencies rather than the amount of variation, enabling you to select 9 different turnover frequencies in either of the bass and treble ranges. Lux's acclaimed NFb type controls assure smooth variation curve without spoiling sonic quality.

Ultimate Pure Sound
The key portions of the chassis are copper-plated to remove the magnetic distortion that triggers modulation of music signals, and the copper-foiled styrol capacitors wrapped by butane rubber totally banish mechanical resonance that is converted into electrical distortion, thus providing the ultimate purity in sonic quality
Purification of Amp Circuitry
For thorough expression of the core of music , highly purified sonic quality is required, and only when the amp circuit is simplified such purest sonic quality is yielded. The ideal, simplest "Single-Stage" Amp is brought about with elimination of the entire one amplification stage in the form of to , which has throughly solved all the problems associated with the multi-stage amplification such as adverse effect of mains noise, deterioration of slew rate caused by stagger treble compensation, etc.
Puryfication of Erth Circuitry
The earth circuit provides "reference" to all the operations of amp, and the immobile grounding point is the basic condition of a good amp. First we banished the mains-referenced amp circuit and employed all the clean, earth-referenced amp circuits. Then the input and output loops of curret were reviewe at each amp circuit to provide an utter independence to each of them.  And our exclusive Star circuit with discrete placement of erth-line from the reference point to each circuit totally removes harmful inter-earth-line or inter-stage distortion.

Power output: 50 W per channel at 8Ω (both channels driven, 20 - 20,000 Hz)
T.H.D.: no more than 0,005% (8Ω, 20 - 20,000 Hz, -3 dB)
Rated IM: no more than 0,005% (8Ω, -3 dB, 60 Hz:7 Khz = 4:1)
Input Sensitivity & Impedance:
Phono MM: 2 mV/50 kΩ
Phono MC: 90μV/40Ω, 100Ω
Tuner, Line, CD: 150 mV/40 kΩ
Main-in: 150 mV/47 kΩ
Signal-to-Noise ratio (IHF-A weighted):
Phono MM: better than 86 dB (input 5 mV)
Phono MC: better than 80 dB (input 250μV)
Tuner, LIne, CD: better than 110 dB (input short-circuited)
Frequency response:
Phono MM/MC: 20 - 20,000 Hz, ±0,2 dB
Tuner, Line, CD: 10 - 100,000 Hz -1 dB
Main-in: 10 - 100,000 Hz, -1 dB
Tone control:
Max. variable amount: ±9 dB
Bass turnover frequencies: 55 Hz, 77 Hz, 110 Hz, 155 Hz, 220 Hz, 310 Hz,440 Hz, 620 Hz, 880 Hz
Treble turnover frequencies: 620 Hz, 880 Hz, 1.2 kHz, 1.7 kHz, 2.5 kHz, 3.5 kHz, 5 kHz, 7 kHz, 10 kHz
Pre Out: 150 mV
Additional features:
Subsonic filter (15 Hz) and High-cut filter (9 kHz);
Pre-heat switch; Warm-up indicator; Phono-straight & CD-straight switches;
Signal-off switch; Recording switch; Tape monitorand tape dubbing;
Speaker selector, etc.
Dimensions (W x H x D): 453 x 174 x 470 mm
Weight: 20 kg

Pioneer RT-1020L (1973)

Pioneer's advanced new open reel tape deck, the RT-1020L, is designed for tape enthusiasts who wouldn't look or listen twice at even the finest cassette decks, and who are seeking the ultimate of stereo tape performance. Luxuriously constructed with only the finst materials, built for years of rugged and dependable use under all operating conditions.

The RT-1020L offers remarkable cost/performance adventages, a variety of operating conveniences and the versatility that only an expensive machine can provide. Mechanically sound from three-motor tape transport, including six-pole induction motor, to extra-thick chassis and die-cast framework, the RT-1020L delivers the kind of reliability that only a studio engineer would appreciate. precision performance is another aspect of its all-around dependability, for this deck employs a 4/8 pole two-speed hysteresis synchronous motor, unusually accurate capstan - and then adds the new contour-less hyperbolic-type tape heads for high sensitivity and signal-to-noise ratio.

Indicative of its true professional capability, the RT-1020L accepts the large 10½ inch (267 mm) reels, rare for a deck of this attractive price. These extra-size reels permit twice the recording and playback time of ordinary 7 inch reels. You can thus record extra-long symphonies, or other musical performances, without reel or tape changing. And then for four-channel reproduction, the unit is equipped with a four-track in-line tape head and four-channels tapes now on the market. There are many other features, too, that make the Rt-1020L the tape deck buy of the year, no matter which other deck you might have been thinking of buying - and no mater how unlimited is your tape budget. For true tape deck value, no one ever has surpassed Pioneer.

Specifications RT-1020L

3-motor and 3-head Open Rell Stereo tape Deck

System: Stereo recording & playback, 4-channels playback, solenoid operated control


1 x 4-track, 4-channel playback operations;

1 x 4-track, 2-channel recording;

1 x 4-track, 2-channel erese


For Reel: 6-pole inner rotor induction motor x 2

For capstan: 4/8-pole hysteresis synchronous motor x 1

Tape speeds: 7½ and 3¾ ips (19 and 9,5 cm/s)

Wow & Flutter: 0,08% WRMS (7½ ips); 0,10% WRMS (3¾ ips)

S/N ratio: more than 55 dB

Distortion: less than 1%

Frequency response:

40 - 20,000 Hz, ±3 dB (7½ ips);

40 - 12,000 Hz, ±3 dB (3¾ ips)

Crosstalk: more than 60 dB

Stereo channel separation: more than 50 dB

Erase ratio: more than60 dB

Recording bias frequency: 125 kHz


Microphone: 0,25 mV to 80 mV/20 kΩ (1mV reference)

Line input: 50 mV t0 25 V/100 kΩ (316 mV reference)

DIN: 15 mV to 1,5 V/1,5 kΩ


Line: 316 mV/50 kΩ load with output level controlat max. Output impedance 3,3 kΩ

DIN: 316 mV/50 kΩ load with output level controlat max. Output impedance 3,3 kΩ

Headphone: 40 mV/8 kΩ with output level controlat max. Load impedance 4 - 16 kΩ

Features: 3-step bias selector, 2-step equalizer selector

Power requirements: 110, 120, 130,220,240 V AC, 50/60 Hz

Power consumption: 115 W

Dimensions (W x H x D): 440 x 431 x 227 mm (17-5/16" x 16-31/32" x 8-15/16")

Weight: 21 kg (46 lb 3 oz) without package

Revox B 77

A well designed tape transport mechanism will not distort mechanically. It is insensitive to shocks and vibrations and will retain these qualities over a wide range of temperatures. Therefore, REVOX B77 tape recorders use diecast parts for the motor chassis, the side bearers, the crossmember and for the head block and the pinch roller arm. This ensures exceptional stability for the precision tape guiding system and the sound heads, as well as for the motors and the brake assembly. The motors are sturdy AC asynchronous types - unbeatable in simplicity and reliability - thus especially suited for heavy duty use.

Magnetic tape recorders are an outstanding example of the perfect combination of precision mechanics and top performing electronics. Even the best electronic circuitry would soon become worthless if the original precision in tape guiding is lost as a result of insufficient long term stability. One of the basic requirements, therefore, is to ensure stable performance for years with a rigid mechanical design which disregards the possible advantages that may lie in 'such tempting advertising claims as 'feather weight' and "slim line?!

Speed control via servo electronics

In 1967 STUDER REVOX had already ushered in the age of electronic capstan speed control for domestic tape recorders. Ever since then many have tried to copy it yet they have never been able to match its simplicity and effectiveness. The principle of electronically regulating a sturdy asynchronous motor by means of a separate precision reference has stood the test so well that it has been adopted for the STUDER professional tape recorders years ago. The capstan motor and its precision reference combined with the inductive speed sensor and its control circuits form a regulating loop which is highly insensitive to variations in power line voltage and frequency or changes in load. This system, which has proven its reliability in more than half a million tape drives, combined with ideal tape guiding results in outstanding motion stability (freedom from wow and flutter which remains unchanged for years. The remarkable mechanical and electronic stability of the complete tape transport mechanism makes it well suited for mobile operation by powering from car batteries in conjunction with an inverter.

For pitch matching or to achieve special effects, motor speed can also be varied continuously over a wide range with the help of an external speed control. The Revodur all metal heads for recording and playback, the erase head, the infrared tape sensor and the tape guides; all these components are mounted on a rigid die-cast frame. A fourth magnetic head can be fitted to record automatic slide synchronizing control signals (DIA/DHA/FH). These signals are recorded within the guard band of the tape allowing their use with normal stereo signals. As far as development of magnetic sound heads is concerned, STUDER REVOX is looking back on an experience which equals that of building tape recorders. Our experts manufacture all metal heads for REVOX B77 tape recorders and for professional sound recorders. The special alloy Revodur ensures excellent magnetic properties and outstanding wear characteristics. The shape of the head's face is designed to ensure a "ruler flat" response down to the lowest audio frequencies. Ease of editing

The practical edit facility is standard equipment on each Revox B77 recorder. By operating the sliding button, the tape is brought into contact with the heads, the playback amplifiers become activated and the fast wind buttons respond only as long as they are held depressed. This facilitates motor assisted searching for the edit point while final tape positioning is then performed manually. The thoughtful design of the lower control panel facilitates easy access to tape heads for accurate tape marking. An ingenuously conceived edit mode facilitates motor assisted tape shuttling and final manual locating of the exact edit point. B77 versions

Part of the B77 head block, showing the roller bearing tape guide and infra red tape end detector. The integrated tape cutter helps to make editing a simple task. Track configurations: Half track (S2):

Half track models are always selected when tape splicing (editing) is required. Because of the large track width of 2mm, these models feature excellent ratings with respect to frequency response and treble dynamic range. The half track version can be equipped with slide control electronics and an additional sound head. The high-speed version of the half track machine is ideally suited for applications requiring maximum audio quality (e.g. as effects machine in audio or film production). The quarter track (S4): The advantage of quarter track machines over half track machines is the double tape capacity. The quarter track B77 is suited for applications where long playing times (up to six hours on the standard speed B77) combined with excellent audio quality is essential. The quarter track machines can also be equipped with side control electronics and an additional sound head. Because of the narrower track width, the audio specifications are in certain areas slightly inferior to those of half track machines. The quarter track configuration interleaves the two stereo tracks. This allows the reels to be "turned over" allowing double the recording time The half track configuration uses the full width of the tape to lay down a stereo image. (excluding the guard band) Standard version of B77

Direct drive capstan motor with tacho generator and servo electronics to ensure outstanding speed stability independent of variations in load or changes in the electrical supply voltage or frequency. Magnetic tape recorders are an outstanding example of the perfect combination of precision mechanics and top performing electronics. Even the best electronic circuitry would soon become worthless if the original precision in tape guiding is lost as a result of insufficient long-term stability. One of the basic requirements therefore, was to ensure Revox B77 stable performance for years, achieved with a rigid mechanical design, which disregards the possible advantages that may lie in such tempting advertising claims as "feather weight" and "slim line"! Precision cannot be realized without ruggedness. This is the reason why all important parts of the B77 transport mechanism are made from solid die-castings. Speed control via servo electronics

Tape transport mechanism:

Three motors; 2 AC reel motors; 1 AC capstan motor, electronically regulated

Tape speeds:

9,5 and 19 cm/s, electronic switching, speed accuracy ±0.2%

6,5 and 28 cm/s external speed variation

Wow and flutter (DIN 45507):

At 9,5 cm/s <0.1%,

At 19 cm/s <0.08%

Tape slip: Maximum 0.2%

Reel size:

Up to 26,5 cm (10.5”) diameter, minimum hub diameter 6 cm (2.36”)

Tape tension switchable for small hub diameters

Rewind time:

Approximately 135 seconds for 1100 m (3,600 ft) of tape

Tape transport control:

Integrated control logic with tape motion sensor provides for any desired transition between different operating modes. Electronic motor control (without brushes); all functions can be remote controlled

Equalization (NAB):

9,5 cm/s (3.75 ips): 90/3180 microsec

19 cm/s (7.5 ips): 50/3180 microsec

Frequency response (measured via tape at -20 dB VU):

9,5 cm/s (3.75 ips): 30 Hz - 16 kHz +2, -3 dB and 50 Hz - 10 kHz ±1.5 dB

19 cm/s (7.5 ips): 30 Hz - 20 kHz +2, -3 dB and 50 Hz - 15 kHz ±1.5 dB

Max. recording level: 514 nWb/m corresponds to +6 dB VU

Level metering:

VU meter to the ASA standard, with LED peak level indicators


9,5 cm/s (3.75 ips): <1% (0 dB VU, 257 nWb/m); <2,5%, (6 dB VU, 514 nWb/m)

19 cm/s (7.5 ips): <0,6% (0 dB VU,257 nWb/m); <2%, (6 dB VU, 514 nWb/m)

Signal to noise ratio (ASA A weighted):

Half track

9,5 cm/s (3.75 ips) >63 dB

19 cm/s (7.5 ips) >69 dB

Quarter track

9,5 cm/s (3.75 ips) >60 dB

19 cm/s (7.5 ips) >63 dB

Crosstalk (at 1 kHz):

Stereo >45 dB,

Mono >60 dB

Erase depth: >75dB at 19 cm/s (7.5 ips)

Inputs per channel:

Mic Low: 0.15 mV/2,2 kΩ for 50 - 600 Ω impedance microphones

Mic High: 2.8 mV/220 kΩ for high impedance microphones

Radio: 2.8 mV/20 kΩ

AUX: 40 mV/1M Ω

Outputs per channel (Level at 6 dB VU, 514 nWb/m):

Output: 1.55 V/390 Ω

Radio: 1.55 V/4,7 kΩ

Phones: 5.6 V/220 Ω

Connectors for:

Remote control mechanism

Remote control of variable tape speed

Slide projector or crossfade unit (electronics optional)


11 ICs, 1 opto-coupler, 4 triacs, 60 transistors, 33 diodes, 5 LEDs, 2 full wave rectifiers, 3 relays

Electric current supply:

100 - 240V 50/60 Hz

Voltage selector for 100V, 120V, 140V, 200V, 220V, 240V

Maximum consumption power: 80 watts

Main fuse 120V 1A slow-blow, 240V 0.5A slow-blow

Dimensions (W x H x D): 452 x 414 x 207 mm

Clearance required for 10.5” reels height 464 mm, width 538 mm

Weight: Approx. 17 kg