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





NAGRA III - tape recorder


NAGRA III (1957) DC servo controlled electric motor. Germanium transistors

The Nagra III is a self contained professional tape recorder, assuring an excellent reliability factor, and the best recording quality available outside your studio. The frequency response, Signal-to-Noise and wow and flutter characterisctics  of the Nagra III, are similar too those of the best studio consol recorders, but modulation noise is even better.

Motor and speed stabilizer
The motor of the Nagra is of the permanent magnet electrodynamic type and resembles a d'Arsonval galvcanometer with central magnet. The Nagra III uses a new technique for controlling the speed of the motor.
The motor carries on its spindle a phonic wheel as well as the capstan, which passes in front of a magnetic head - the tachometer head. This head is magnetised and the rotation of the phonic wheel induces an alternating current, the frequency of which depends upon the speed of rotation of the motor. This passes through the tachometer amplifier  where it is  shaped into a square wave of constant amplitude of about 6 volts peak to peak. This output is taken to a frerquency discriminator. This operates the servo amplifier which controls the motor speed. As the voltage at the servo amplifier becomes increasingly negative, so the motor current will increase.

Microphone preamplifier
This Nagra is equiped with a new type of microphone preamplifier designated LN. This preamplifier permits the selection of input impedance  between 50 Ω and 200 Ω. All that is necessary to do in order to change from one impedance to the other, is to rewire internally the connections on the input transformer.

Specifications:
Electronics:  38 Transistors, 15 Diode, 1 Zener Dode
Tape Speed:  15 ips, 7,5 ips, 3-3/4 ips
Reel Diameter:  7" with cover open, 5" with cover closed
Speed Regulation:  0,05% or better 60/50 Hz buil-in stroboscope
Rewind:  fast rewind and fast forward controls
Magnetic Heads: 
1 High frequency erase head with double gap; 
1 Full track record head; 
1 Full track playback head; 
1 Neopilot sync track head with high frequency  bias
Equalization:  NAB
Inputs:
1 x Microphone  :  50 - 200 Ω impedance
1 x Line ( 600 Ω) or Bridging (100 k Ω)
Line input with BS preamplifier can be used for separate mixing of second microphone.
Line input with BM mixer can be used for separate mixing of three extra microphones plus line input.
Oscillator Frequency:  65 kHz
Output Level:  +15 dbm
Output Impedance:  600 Ω
Frequency Response:
At 15 ips :  30 c/s to 18,000 c/s ±1 dB
At 7-1/2 ips :  40 c/s to 15,000 c/s ±1 dB
Signal-to-Noise Ratio:  75 dB at 15 ips
Erasure:  - 80 dB
Temperature Range:  -4° F to +122°F
Power Consumption:
85 mA : in test mode
175 mA :  in Playback mode
205 mA :  in Recording mode
Batteries:  12 standard Flashlight "D" Cells
Dimensions :  12,5 x 8,7 x 4,3 inch
Weight :  13 lb 13 oz
Recorder Case:  Rugged lightweight metal
Carrying Case:  eveready feather case with or without padding


Teac A-170 cassette deck


The A-170 is the basic cassette machine. But it's basic only when compared to more advanced Teac models. Our entire line is extremely sophisticated, offering quality and features not generally found on less expensive equipment. Every Teac deck must pass a rigid quality control check before leaving the factory, and reliability is almost synonymous with the Teac name. Additional features make some of our products more expensive. But none are more rugged or reliable than the A-170.

The Teac tape transport
The A-170 features a new transport system utilizing many of the ultra-precise parts and design innovations found in our more costly decks. Included among these are the special Teac capstan driveshaft, ground to a tolerance of 1 micron or less. And an all new DC Servo Controlled Motor, with amazing sspeed accuracy. These transport features provide smooth precise tape motion, and wow and flutter is kept to an insignificant 0,09%

High density ferrite heads.
The A-170 features High Density Ferrite heads which are extremely hard and offer a greatly extended life. Teac heads are specially designed to permit distortion-free recording up through the highest audio frequencies.

Expanded range level meters
The key to good recordings is the proper setting of the input levels. The  large, bright meters on thhe A-170 make this easy. The meters are merked to +3 VU but needle range extends to +6 VU to facilitate adjustment for very strong signals and to allow higher than normal recording levels.

Built-in Dolby NR.
The A-170 includes the same Dolby Noise Reduction circuitry found in our top-of-the-line A-450. it reduces tape  hiss and can improve your Signal-to-Noise by as much as 10 dB over 5 kHz. You'll probably use it all the time.

Other important features
Two position switches let you adjust Bias and EQ for either Ferric Oxide or Chromium Dioxide tapes, for maximum performance from both.
The Mic/Line switch allows you to select between "Live" recording from microphones or recording from other audio sources, and cuts in a built-in pre-ampifier  when microphones are used.
Built into the A-170's transport system is an advanced Auto-Stop mechanism. Whenever the end of the tape is reached, the transport automatically returns to the Stop mode.

Specifications
Track System:  4-track, 2-Channel Stereo
Motor:  DC-Servo Controlled Motor
Heads: two. Erase and Record/Playback heads
Tape Type:  Compact Cassette C-60 and C-90
Wow and Flutter:  0,09% (NAB weighted)
Frequency Response (overall):  30 - 16,000 Hz (CrO₂ tape); 30 -13,000 Hz
Signal-to-Noise Ratio (overall):  50 dB (can be improved with Dolby NR up to 5 dB at 1 kHz and 10 dB over 5 kHz)
Rewind/Fast Forward Time:  100 seconds for C-60
Inputs Sensitivity /Impedance:
Line :  2 x 60 mV/50 k Ω
Microphone :  0,25 mV (-72 dB)/600 Ω or more
Outputs
Line :  2 x 0,775 V/ 50 k Ω
Headphone :  Jack, 8 Ω
Power Requirement:  100/117/220/240 V AC, 50/60 Hz
Power Consumption: 8 W
Dimensions (W x H x D):  430 x 136 x 225 mm (16-15/16" x 5-3/8" x 8-7/8")
Weight:  4,5 kg (10 lbs) net


Yamaha NS-410


Bookshelf convenience 4-channel rear speaker adaptbility natural Sound performance.
yamaha NS-410
NS sound. you've heard of the great things it does for music, broadcasting every note with full, rich harmonics, incredibly brilliant highs and sonorus lows. now it's yours in ultra-compact bookshelf wall mount speakers perfect for small-room stereo or as rear speakers for the finest 4-channel systems.
A new Yamaha breakthrough brings you the same Natural Sound we pioneered with our world-famous flat types, in these lighter, more compact cone speakers.

JA - 2054 of 20 cm cone type Woofer is carried in low - pass.
Cone paper is made of pulp and wool blended material with large internal loss, and by using rubber type damping material in combination, suppression of divided vibration.
Phenol rubber type support material is applied to the edge and the dip of the frequency characteristic generated from the vicinity of the edge is prevented.

In the high region, JA - 0507 of a show with a structure close to the dome type and a tweeter with horn mixed with horn type and cone type is carried.
Mylar is adopted as the diaphragm, bobbin is removed to lighten the vibration system, and the diaphragm and the aluminum ribbon wire edgewise voice coil are directly connected.
Furthermore, a brake element made of expanded urethane was tried between the diaphragm and the center pole, and excellent high frequency characteristics were obtained.
Also, the directivity is improved by a special section close to the dome.

Specifications:
Type:  2-way 2-speaker
Frequency:  85 Hz - 18,000 Hz
Output Sound Pressure Level:  94 dB / W / m (New JIS)
The Lowest Resonance Frequency:  85 Hz
Drivers:
For low-pass:  20 cm cone type (JA-2054)
For high range:  dome type (JA - 0507)
Crossover:  5 kHz, 6 dB/oct, 12 dB/oct
Impedance:  8 Ω
Dimensions:  310 x 488 x 180 mm.
Weight:  6,5 kg
Finish:  White or Rosewood

Yamaha HP-3 headphones

Yamaha invites you to enjoy a private word of musical enjoyment. Light, and with the gentlest of ear-pad pressures, the HP-3 headphones are a transparent window on the world of music.
Wide frequency response and low distortion combine to give a clear and uncolored reproduction superior to the finest loudspeakers. And you can enjoy the full, shattering sound levels of hard rock, or grand opera, without disturbing those around you. They also assure faithful and delicate reproduction of a whispered vocal, or a solo violin. Orthodynamic design is the secret.
With the HP-3 you may well forget that you are wearimg headphones. But you will never forget the thrilling realism that they bring to your private musical enjoyment.

Specifications;
Type:  Orthodynamic Type
Impedance:  150 Ω
Diaphragm Diameter:  46 mm
Sensitivity:  93 dB/mW, 101 dB/V
Max. Continuous Input:  1 W
Max. Input: 3 W
Weight: 210 g (with cord)


Tannoy Mercury F4



Features:
F4 utilises a 1-inch  (25 mm) Nitro-urethane layer-damped woven polyester dome tweeter and a powerful neodymium magnet assembly.
Two 6,5-inch (165 mm) Bass drivers utilise extremely lightweight multi-fibre coated pulped paper cone offering exceptional rigidity.
Finish is available in apple wood or dark oak vinyl veneer
Recommended amplifier power from 10 to 140 Watts RMS

Specifications
Enclosure Type:  Front reflex braced encloseure
Drivers
High Frequency :  25mm (1.00") soft dome tweeter
Low Frequency:  Two x 165mm (6.50") bass driver
Frequency Response (at 3dB):  35 Hz to 20 kHz
Amplifier Power Range:  10 to 140 watts / channel
Crossover Frequency:  2.7 kHz
Maximum Power Handling:  200 watts / cannel
Sensitivity:  91 dB
Impedance:  8 Ω
Effective Volume:  40.0 Litres
Weight:  13.5 Kg
Finish:  Apple Wood or Dark Oak



Pioneer SX-990 Receiver


AM/FM Multiplex Stereo Receiver
 Never has any receiver combined such exceptional high performance with so many audiorefinemental a full 100W at 8 ohms over a frequency response from 10 to a fantastic 100,000 Hz Advanced solid state circuitry with Field Effect Transistor and Integrated Circuits and a 4-gang variable capacitor - for significantly superior sensitivity and limiting. Two tuning meters, an unusually wide range of inputs and outputs, precise tone controls and a host of important innovations. Meticulously engineered. Stunningly styled. Truly one of the finest audio components ever created.
Features
High-performance FM Tuner
An FET (Field-Effect Transistor) is used in the radio-frequency amplifier to attain a high sensitivity and selectivity. Further, four ICs (Integrated Circuits) are used for the intermediate frequency amplifier to eliminate interference and noise.

 Built-In Excellent FM MPX Circuit
This switching circuit having excellent separation and frequency response is built in for reproduction of reality music.

 Built-In Highly-Sensitive Ferrite Antenna for AM Radio Reception
The ferrite antenna provides high-sensitivity reception of AM broadcast programs.

Special Curcuitry for Versatility
The high output given by strictly selected transistors, two sets of loudspeaker terminals and phono terminals, and the provision for using a microphone make Model SX-990 suitable for the professional use as well as the family use.

A variety of Accessories
Accessories include the program lamps that indicate the program being played, the tuning meters vertically arranged for facilitating selection of an FM broadcast program, the loudspeaker selector switch, tape monitor switch, etc, all for enjoyable use of Model SX-990.


Specifications
Audio Section
Circuitry:  Single ended push pull
Semiconductors:  25 Transistors; 5 Diodes
Music Power Output (IHF Rating):
100 watts total at 8 Ω
130 watts total at 4 Ω
Continous Power Output
Each channel driven:  35 W / 35 W at 8 Ω
Both channel driven :  28 W + 28 W at 8 Ω  (30 W + 30 W at 4 Ω )
Total Harmonic Distortion:  less than 0,5% (at 1 kHz rated output)
Frequency Response:  10 Hz tp 100 kHz ±3 dB ( Overall)
Power Bandwidth:  15 Hz to 40 kHz (AUX)
Hum and Noise:
Mag :  better than 80 dB
Aux :  better than 100 dB
Input Sensitivity/Impedance:
Magnetic Phono :  3,3 mV / 50 k Ω
Ceramic Phono :  24 mV / 100 k Ω 
Microphone :  5 mV / 100 k Ω
Tape Monitor :  200 mV / 100 k Ω
Aux :  200 mV / 100 k Ω
Main In :  530 mV / 100 k Ω
Output Terminals Impedance:
Speakers :  4 to 16 Ω
Equalization Curves:  Phono RIAA
Tone Controls
Bass :  boost 11 dB/oct, cut 16,5 dB at 50 Hz
Treble :  boost 10 dB , cut 9,5 dB at 10 kHz
Filters
Low :  cut 8 dB at 50 Hz
High :  cut 7,5 dB at 10 kHz
Loudness Contour:  boost 12 dB at 50 Hz, boost 9 dB at 10 kHz (switchable to On-Off ( vol. Control at  -40 dB)
FM Section
Circuitry:  Front end using FET end 4 gang variable capacitor, IF amplifier 4 IC
Semiconductors:  1 FET, 5 ICs, 11 Transistors, 12 Diodes
Frequency Range:  87,5 to 98 MHz
IHF Usable Sensitivity:  1,7 µV
Image Rejection:  87 dB (at 98 MHz)
Signal-to-Noise Ratio :  62 dB (IHF rating)
Antenna Input:  300 ohms (balanced)
Multiplex Section
Circuitry:  Time-switching type de-modulator FM Mono Stereo Automatic selection
Channel Separation:  42 dB (At 1 kHz)
AM Section
Circuitry:  Superheterodyne
Frequency Range:  525 to 1605 kHz
IHF Usable Sensitivity:  18 µV
Image Rejection:  77 dB (at 1000 kHz)
Antenna Input:  Built-in Ferrite Loopstick Antenna
General Section
Line Requirements:  110, 117, 130, 220 and 240 V; 50 - 60 Hz;  210 VA 190 watts (max)
Dimensions (W x H x D):  459 x 145 x 369 mm (18-1/16" x 5-11/16" x 14-1/2")
Weight: 11,4 kg (26 lb 2 oz) net


Acoustic Research AR 302T


The AR 302T is new 3-way Tower Loudspeakers are engineered  to deliver maximum sonic performance at a tremendous value. Utilizing AR's True Acoustic Suspension Technology and Exposed Dome Driver Technology, these floorstanding models reproduce the wide dynamic swings of music and video with the tonal accuracy and flat frequency response you've come to expect from Acoustic Research, AR 302 Towers minimal footprints require less floor space for increased placement flexibility, and their Matched Timbre Design ensures harmonious integration with AR bookshell models for seamless, rtunning home theater sound. Their elegant cherry cabinetry on all four sides presents a striking, contemporary appearance.


Specifications:
System Type:  10" 3-way Acoustic Suspension Tower Speaker
Driver Usage: 
10" long-throw woofer
1-1/2" exposed dome midrange
3/4" exposed dome tweeter
Frequency Response:  32 - 20,000 Hz (±3 dB)
Sensitivity:  85 dB (2,83 V/m)
Impedance:  6 Ω / 4 Ω (nom/min)
Power Rating:  35 W - 250 W (min/max)
Crossover: 
650 Hz (12 dB/oct low-pass; 12 dB/oct high-pass)
5,500 Hz (6 dB/oct low-pass; 18 dB/oct high-pass)
Dimensions (W x H x D):  11 x 36 x 13 inch
Weight:  47 lbs
Finish:  Cherry vinyl


Acoustic Research AR 338T

 The AR 338T is new 3-way Tower Loudspeakers are engineered  to deliver maximum sonic performance at a tremendous value. Utilizing AR's True Acoustic Suspension Technology and Exposed Dome Driver Technology, these floorstanding models reproduce the wide dynamic swings of music and video with the tonal accuracy and flat frequency response you've come to expect from Acoustic Research, AR 338 Towers minimal footprints require less floor space for increased placement flexibility, and their Matched Timbre Design ensures harmonious integration with AR bookshell models for seamless, rtunning home theater sound. Their elegant cherry cabinetry on all four sides presents a striking, contemporary appearance.
Specifications:
System Type:  8" 3-way Acoustic Suspension Tower Speaker
Driver Usage: 
8" long-throw woofer
1-1/2" exposed dome midrange
3/4" exposed dome tweeter
Frequency Response:  47 - 20,000 Hz (±3 dB)
Sensitivity:  86 dB (2,83 V/m)
Impedance:  68Ω / 4 Ω (nom/min)
Power Rating:  35 W - 150 W (min/max)
Crossover: 
900 Hz (12 dB/oct low-pass; 12 dB/oct high-pass)
6,000 Hz (12 dB/oct low-pass; 12 dB/oct high-pass)
Dimensions (W x H x D):  9 x 32 x 11 inch
Weight:  38 lbs
Finish:  Cherry vinyl


Sony APM-77 W

A bookshelf-type 3-way speaker system that's all APM, with performance comparable to floor-standing studio monitors. The flat and square woofer is driven by 4 independent voice coils with direct dual-surface drive for outstanding low frequency response and resolution.
Maximum power handling capacity of 200 W.

 The Sony APM-77 is the original "affordable" APM loudspeaker. It sported a stark grey finish and was thus quite futuristic. However, as the 1980s turned out to be far more conventional than expected, it is the later APM-77W (W for Wood) that is well remembered. Unfortunately, wood or not, the APM-77 didn't sell that well although it does provide a very balanced sound.
APM drivers are made of an aluminium honeycomb mainframe with ultra-thin aluminium covers - 100x more rigid than paper cones. The japanese magazine Audio Accessory often used Sony's APM loudspeakers for its reviews.
Specifications:
System:  3-way, Bass-reflex
Speakers:
Woofer :  530 cm² APM
Midrange :  27 cm² APM
Tweeter :  7 cm² APM
Impedance:  6 Ω
Power Handling Capacity [Nominal/Maximum] :  100 / 200 W
Sensitivity:  90 dB/W/m
Frequency Range:  28 - 30,000 Hz
Dimensions (W x H x D):  405 x 745 x 325 mm
Weight:  32 kg


Technics SB-E100 loudspeakers


High Efficiency, High Input Resisting 30 cm Woofer
In order to make the most of the horn type speaker system, the wofer is required to be highly efficient and to have a frequency characteristic to go smoothly with the mif-range. In this respect, the system uses Canadian coniferous pulp and cones with liner elements combined, thus assuring a high efficiency of 95 dB/W/1m. Also, to improve the linearity coping with a large input, well ventilated high compliance dampers and non-directional urethane edges are employed. Furthermore, polyester insulator and polyamide layers are used for the voice coils, and extra-high heat resisting resin film is used for the bobbins so that the system is able to withstand continuous since waves of as high  as 100 Watts (DIN RMS).

Wide-directional Radial Horn Mid-range
Frequency characteristics with wide-band and excellent directivity are obtained with a radial horn widening at 150 deg. From aluminum die-cast horn throat and newly developed shell type equalizer (mid-range). The driver section is made of extra-thin aluminum alloy of 35ф, 30 µm thick, and the edge, provided with slits, employes perforated pole pieces to improve the low-range characteristic, and is high input resisting with heat radiating aluminum bobbin of µm, CCAW (copper coated aluminum wire), and heat resisting voice coils.

Wide-directional Radial Horn Tweeter
This wide-directional radial horn, widening at 150 deg., is of high precision solid type made of aluminum diecast. The driver section consists of metalized polyester film vibrating reeds and employs a powerful magnetic circuit using a large aluminum magnet, and is high input resisting with use of heat resisting voice coils.

Linear Phase Network
Linear phase characteristics are obtained by a dividing network combining 12 dB/oct and inductive M types, thus making reliable transfer of waves possible. Also, low-distortion filament cores are employed for choke coils.

Control Tower
It is equiped with a thermal relay protection circuit in oreder to protect the mid-range and tweeter from excess input or abnormal signals. Also, to use it as a multiamp system, it is provided with multi-amp input terminal along with a multi-amp switching connector. Besides these functions, dividing network, level control and input terminal are concentrated at the control tower which also serves to secure drivers of the mid-range and tweeter, thus improving the controllability.

Power Handling Capacity
The power handling capacity of this speaker system is 150 watts (music), and 100 watts DIN (RMS).
Speaker Protection Circuit
This system is equipped with a speaker protection circuit to protect the speaker from excess input or abnormal signals. If excess input is applied to the speaker, it will be automatically cut off by the protection circuit.

Multi-Amp System
The impedance of each unit woofer, midrange and tweeter is 6 Ω . Therefore, make sure that the load impedance of the amp used ranges from 4 Ω  to 16 Ω
When the multi-amp switching connector is set to "multi amp system", the network, level control and protection circuit of this system are disconnected. The sound volume of each unit can be adjusted by turning the volume knob of each amp.
It is recommended to use the system with crossover frequencies between speakers  as follows:
Woofer - Midrange :  1,2 kHz - 2 kHz
Midrange - Tweeter :  5 kHz - 10 kHz
In order to protect the speaker unit against low-range noise from the amp, connect a bipolar condenser of about 68 µF between amp and speaker, and about 10 µF to tweeter respectively in series.

Specifications
Type:  3-way, 3-speaker system
Speakers:
Woofer :  300 mm (12") cone type
Midrange :  Horn type
Tweeter :  Horn type
Impedance:  6 Ω
Input Power:
Music :  150 W
DIN :  100 W (RMS)
Output Sound-Pressure Level:  95 dB/W /1m
Crossover Frequency:  1500 Hz, 6500 Hz
Frequency Range:  37 - 22,000 Hz
Dimensions (W x H x D):  525 x 846 x 424 mm (20-5/8" x 33-1/4" x 16-5/8")
Weight:  29 kg (63,9 lbs)



Akai GX-230D reel-to-reel


AC Servo Capstan Motor and GX head characteristics assure  complete tape travel stability and long lasting performance. Automatic and Manual Reverse Playback.

Integrated Akai Quality Features for Unparalleled Performance
New AC Servo Motor
The new Akai AC Servo Motor employed in this model for direct capstan drive is equipped with 114 gears on both the rotor and stator sides and a detector coil and magnet are built in on the stator side for a completely new pulse detection system. With this system, pluse detection is made only once every 114 pluses instead of at each pulse for greatly increased pulse output.

Symmetrical head Block, Impedance Roller, and tension Arms for even tape travel in both directions.
For perfectly equal tape speed and even tape tension is both directions, the head block layout is of symmetrical design and the machine is equipped with an impedance roller and tension arms. These features function together as integral parts of this GX Head, AC Servo Motor system for unparalleled stability and long-lasting quality performance.

Automatic and Manual Reverse Playback.
Automatic Reverse Playback is as simple as applying a piece of sensing foil to the tape at desired reversing point. Manual Reverse Buttons  can be operated at any time during plauback.

All GX heads
One each GX Forward Playback, GX Reverse Playback, and combination  GX Recording/Erase head guarantees long lasting performance. As is well known, the core of these heads are made of single crystal and are mounted and set in glass. The wear-free characteristics of these materials permit a perfectly lineal head gap for a "focused field" system and optimum head-to-tape contact which results in a wider dynamic range with excellent Signal-to-Noise ratio.

Specifications:
Track System:  4-track, 2-channel stereo/monaural
Reel Capacity:  up to 7" reel
Tape Speed:  7-1/2 and 3-3/4 ips
Wow and Fluter: 
less than 0,06% WRMS at 7-1/2 ips;
less than 0,08% WRMS at 3-3/4 ips
Frequency Response: 
Low Noise Tape LN-150-7 :
30 - 23,000 Hz (±3 dB) at 7-1/2 ips
30 - 19,000 Hz (±3 dB) at 3-3/4 ips
Distortion:  less than 1,0% (1,000 Hz, 0 VU)
Signal-to-Noise Ratio (measured via tape with peak recording level of +6 VU):  Better than 60 dB
Erase Ratio:  better than 70 dB
Bias Frequency:  100 kHz
Heads: 
1 x  GX recording/erase combination heads,
1 x GX Forward Playback,
1 x GX Reverse Playback
Motors: 
1 x AC Servo Motor for  capstan drive ;
2 x Eddy-current motors for  reel drive
Fast Forward / Rewind Time:  75 sec using 1200 ft tape
Output Jacks:
Two Line :  0,775 V, "0" VU (required load impedance more than 20 k Ω)
One Phono :  30 mV/ 8 Ω
Two Speaker :  Continuous Power Output 7 watts per channel minimum RMS at 8 Ω load impedance from 100 Hz to 20,000 Hz, both channels fully driven to rated per channel power with no more than 3% Total Harmonic Distortion
Input Jacks:
Two Line :  70 mV
Two Microphone :  0,3 mV/4,7 k Ω
DIN Jack:  0,5 V/25 mV
Semiconductors:  41 Transistors, 28 Diodes,
Power Requirements:  100 V to 240 V AC, 50/60 Hz
Power Consumption:  90 W
Dimensions (W x H x D):  440 x 395 x 205 mm (17,3 " x 15,6" x 8,1")
Weight:  15,2 kg (33,4 lbs)



Sony TC-270 reel-to-reel

The Sony Stereo Tape-recorder TC-270 is a complete stereo tape recorder. This compact, powerful stereo music system consists of an amplifier utilizing Sony silicon transistors, precision tape deck and high performance speaker systems.
The tape transport mechanism, including vibration-free motor, is designed to provide flutter-free, stable tape drive either in vertical or horizontal operation.tape modulation distortion noise is remarkably reduced by the scrape filter.
Other features are; automatic shut-off device, retractomatic pinch roller for easy tape threading, the professional recording techniques of Sound-to-Sound, built-in reel locks and many more.

Specifications:
Tape Speed:  7-1/2, 3-3/4, 1-7/8 ips
Recording Time:  1,5 hours total at 7-1/2 ips, stereo recording with 1,800 ft tape
Reels:  7" or smaller
Semiconductors:  18 transistors; 4 diodes
Recording System:  4-track stereo or monaural
Heads:  1 x Record/Playbak head;  1 x Erase head
Signal-to-Noise Ratio:  50 dB
Distortion:  3%
Frequency Response [NAB / DIN] : 
7-1/2 ips ;  30 - 18,000 Hz / 30 -16,000 Hz
3-3/4 ips ;  30 - 13,000 Hz / 40 -12,500 Hz
1-7/8 ips :  30 - 7,000 Hz / -
Wow and Flutter [NAB / DIN}:
7-1/2 ips;  0,12 % / 0,18%
3-3/4 ips :  0,15% / 0,25%
1-7/8 :  0,2% / -
Inputs:
Microphone Inputs
Sensitivity :  -72 dB (0,2 mV) / accept low impedance microphones
Line Inputs
Sensitivity :  -22 dB (0,06V)
Impedance:  160k Ω
Outputs
Line Outputs
Outputs level :  -5 dB (0,43 V)
Load Impedance more than 10 k Ω
Speaker Outputs
Load Impedance :  8 Ω
Headphone Output
Accapts an 8 Ω stereo headphone
Record/Playback Connector
Input Impedance :  3,9 k Ω
Output Impedance :  80 0hm
Power Requirement:  AC 220 V, 50 Hz; AC 110,127, 220, 240 V , 50/60 Hz
Power Consumption:  AC 55W
Dimensions (W x H x D):  513 x 260 x 387 mm
Weight:  16,5 kg (36 lb 6 oz)


Genesis APM-1 loudspeakers


The Genesis APM-1 embodies our commitment to the shattering of traditional high-end loudspeaker price-to-performance ratios. With a stunning new form factor and engineering innovations that belie their cost, our new APM-1 is a ideal audio/video loudspeaker system, offering unprecedented ease of placement in your listening environment.. Their sleek modern industrial design encompasses innovative engineering and driver technology, setting the stage for the captivating performance of the revolutionary new APM-1 from Genesis technologies.

This series of loudspeakers, by virtue of its extraordinary dynamic range and extended frequency response, is perfect for both high-end home audio and video applications. The AMP-1 has in fact been specifically designed to excel in both of these areas.
Like all genesis loudspeakers, the  APM-1 embodies a dipole design producing sound from both the front and the rear, one out of phase with the other. While the advantages of dipole design are many, the two main benefis are ease of placement in the room 9they can even be located very close to a wall boundary) and more natural, spacious sound reproduction.

Dipoles achieve their superior performance because they create a radiation pattern where the energy emanating to the sides of the speakers is nearly non-existent. With very little acoustical energy reaching the side walls of your living room, not only is placement of the speakers easy but, remarkably, the listener is able to experience the music unencumbered by the normal room interactions which plague most other speaker system.

The APM-1 Loudspeakers utilize our most sophisticated technology. Suspended within sculpted cherry wood front baffles measuring a mere 11" wide are four 1" planar ribbon tweeters, a pair of our newly minted titanium midrange modules, as well as four mid-bass couplers. Down below are two 15" aluminum cone servo subwoofers driven by twin intergal G-SAT 500-watt servo-controlled switching power amplifiers.

Drivers.
The tweeter used in both the front and back of the  APM-1 has been described by many reviewers in both the American and foreign Audiophile press as "possibly the world's best". It is a 1" planar ribbon design that is handcrafted from an extremely thin, laminated membrane of aluminum and kapton. It measures a mere 0,0005" thick. The advantage of incorporating such an extremely thin membrane is its low mass. The result of this design is a driver that produces a rapid and uniform response to high frequency transient and has the speed of the best ribbon/electrostatic designs without the characteristic distortion and poor dispersion associated with them.

Our new 5-1/2" midrange driver is machined from pure titanium, one of the lightest and stiffest materials known to man. Its super low mass makes it one of the best transducers ever made. With its nearly instantaneous transient response, this titanium midrange inspires the APM-1 loudspeakers to sound lifelike and effortless. This driver will be incorporated into forthcoming Genesis products costing many times that of the  APM-1.
To create a "sound bridge" between the midrange and the servo-woofer system, the  APM-1 incorporates two of our world-renowed 6-1/2" metal cone mid-bass couplers ( as found in our Genesis V and Genesis 500). Being of an extremely light and stiff design, this metal cone is capable of handling the huge dynamic range demands of the system while maintaining the extremely low coloration and excellent transient response critical in reproducing the classic "Genesis Power Band".
As in all Genesis loudspeakers, the drivers used in the APM-1's are custom crafted devices designed and tuned by Genesis engineers for transparent and dynamic performance.

The APM-1 gets the "low Down"
Servo control of the woofers coupled with metal cone technology are the keys to the phenomenal bass performance of the APM-1. listening to traditional woofer systems, one could describe the bass as "heavy", 'soggy", or "boomy" to some extent because the woofer has high mass and therefore high inertia. This causes poor control and high distortion. In a servo woofer system, complete control of the woofer is made possible by the addition of a motion sensor (accelerometer) mounted directly on the woofer itself. The resultant decrease in distortion, greater frequency extension and tight control yield musically accurate yet "floor shaking" bass.


The servo controlled metal cone woofer system of the APM-1 are driven by the new Genesis G-Sat Amplifier. This unique power plant utilizes an axtraordinary technology known as the switching amplifier, first introduced to the audio world by Genesis co-founder Arnie Nudell. Acclaimed for exemplary performance by virtue of its perfectly linear response, near-perfect efficiency, and "slam factor", our switching amplifier is superior to just about any other form of amplification. In fact, the Genesis servo-bass system forges the best melding of driver and amplifier imaginable, yielding the precise and powerful bass required for today's demanding dual-purpose speaker systems.

Specifications
Frequency Response:  20 Hz to 36 kHz (±3 dB)
Impedance:  4 Ω
Sensitivity:  90 dB
Woofer amp.:  500 watt switching amp. Built-in
Dimensions (W x H x D): 11" x 64,5" x 25"
Weight:  240 lb/each