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





Acoustic Research AR-28BX speakers


Specifications:

System Type:  Floor standing acoustic suspension 2-way system with drive units in a vertical array

Drive Units:

LF :  250 mm (10") acoustic suspension woofer

HF :  25 mm (1") liquid cooled high range driver

Voltage Sensitivity:  2,83 volts produces 89 dB SPL at 1 meter on axis

Efficiency:  1 watt produces 89 dB SPL at 1 meter on axis

Power Requirement:  10 watts per channel minimum

Power Handling Ability:  May be used with amplifiers rated at up to 100 watts per channel

System Frequency Response: -3 dB points at 42 Hz and at 22,000 Hz

System Low Frequency Performance:  -3 dB at 42 Hz with an effective Q at resonance of 74

Impedance:  8  nominal; 5  minimum point

Crossover Network: 

Both woofer and high range have second order electrical networks High range has a second order electrical network

Crossover Frequency:  1800 Hz

Cabinet Internal Volume:  35 liters (1,25 cu lt)

Cabinet Finish:  Walnut grain vinyl veneer

Cabinet Dimensions (H x W D):  689 x 330 x 257 mm (27-7/8" x 13" x 10-1/8")

Weight: 15,9 kg ( 35 lbs) 1 speaker net


 

Acoustic Research AR-8BX speakers


 

Specifications:

System Type:  Bookshelf acoustic suspension 2-way system with drive units in a vertical array

Drive Units:

LF :  150 mm (6") acoustic suspension woofer

HF :  25 mm (1") liquid cooled high range driver

Voltage Sensitivity:  2,83 volts produces 87 dB SPL at 1 m on axis

Efficiency:  1 watt produces 87 dB SPL at 1 m on axis

Power Requirement:  10 watts per channel minimum

Power Handling Ability:  May be used with amplifiers rated at up to 75 watts per channel

System Frequency Response: -3 dB points at 62 Hz and at 25,000 Hz

System Low Frequency Performance:  -3 dB at 62 Hz with an effective Q at resonance of 88

Impedance:  8  nominal; 5,6  minimum point

Crossover Network: 

Woofer has first order electrical networks plus mechanical slope to give a total of 18 dB/octave

High range has a second order electrical network

Crossover Frequency:  4000 Hz

Cabinet Internal Volume:  9,8 liters (35 cu lt)

Cabinet Finish:  Walnut grain vinyl veneer

Cabinet Dimensions (H x W D):  394 x 244 x 187 mm

Weight: 6,6 kg ( 14,5 lbs) 1 speaker net


 

Akai M-10 tape deck

This Three Motors Auto-Reverse Solid State Stereo Tape Recorder offers you perfect stereo hi-fi tape recording and automatic reverse playback with concert hall sound.

 

Outstanding Features

4-track stereo/monaural recording and playback

3 speed  (7-1/2; 3-3/4; and 1-7/8 ips)

3 heads - Erase, Playback/Record and bias heads - Crossfield Head System

3 motors -  A hysteresis synchronous 3-speed motor for capstan drive; Two 6-pole eddy current out rotor motors for supply and take-up reel drive.

Wide Cross-Field Frequency Response

40 W music power solid state amplifier with two integrated circuits

Sensing tape continuous reverse (Auto reverse)

Manual reverse

Shield type head for high Signal-to-Noise Ratio

Sound on sound

Automatic stop/shut off; Instant stop control with start button

Automatic pinch wheel release, Automatic lever release

Two lever system ensures dependable and durable operation

Track selector for simple operation between stereo and monaural

Tape lifter in fast forward and rewind operation

100 kHz biased for FM multiplex recording

Tape speed equalizer

Treble and Bass controls

DIN jack with selector switch for High Low input

Two stereo headphone jacks

4-digit index counter with reset button,

Two large VU meters

Vertical or horizontal operation

Fine oil finished wooden cabinet or vinyl leather wooden cabinet

Universal voltage selector ( from 100 V to 240 V, 50/60 Hz)

 

Cross-Field Head

On conventional recorders the signal and bias are applied to the same recording head. Therefore the frequencies recorded, especially the high frequency component of the recorded signal tend to be attenuated or erased by the effect of the bias field.

On the exclusive Akai Cross0Field Head which was developed by Akai for practical use the signal and bias heads are mounted in opposition with their centres slightly off. As the recorded signal is entirely unaffected by the prevailing effect of the entire frequency spectrum with maximum fidelity.

 

Sensing Tape Continuous Reverse

Automatic reverse with metallic sensing tape is used for playback only. Reverse operation will occur when metalic sensing tape on prerecorded tape makes contact with the Sensing PIN. Put metallic sensing tape as the desired reverse point on shiny side of the prerecorded tape and another metallic sensing tape at the desired reverse point  on dull side of the prerecorded tape. So, the M-10 will give continuous playback in both directions between two points

 


Specifications

Tape Speed: 7-1/2; 3-3/4; and 1-7/8 ips

Wow and Flutter

At 7-1/2 ips :  less than 0,08% rms

At 3-3/4 ips :  less than 0,12% rms

At 1-7/8 ips :  less than 0,20% rms

Frequency Response

At 7-1/2 ips :  30 - 26,000 Hz

At 3-3/4 ips :  30 - 19,000 Hz

At 1-7/8 ips :  30 - 9,000 Hz

Distortion: within 2% 1,000 Hz 0VU

Signal-to-Noise Ratio :  better than 50 dB

Input Level

Mic :  better than 0,5 mV

Line :  better than 50 mV

DIN :  better than 5 mV (Low); 50 mV (high)

Power Output: 

15 W maximum per each channel at Undistorted Power, total 30 W

20 W maximum per each channel at Music Power, total 40 W

Equalization:  Correct equalization for playback of tapes recorded to the NAB curve

Recording Bias Frequency:  100 kHz

Recording Level Indicator:  2 VU meters

Recording System:  4-track stereo / monarual, Cross-Field bias system

Fast Forward and Rewind Time:  75 seconds using 1,200 foot tape at 50 Hz  (60 seconds at 60 Hz)

Recording Capacity: 

8 hours monaural recording at 1-7/8 ips (1,200 foot tape)

4 hours stereo recording a 1-7/8 ips

Max. Reel Size:  7" reel

Head: 3 heads - Erase, Rec/Pb, Bias

Motor:  3 motors- hysteresis synchronous 3-speed motor ; Two 6-pole eddy current out rotor motors

Speaker:  2 - 4" x 6" speakers

Semiconductors:  22 Transistors; 2 ICs

Power Requirements:  AC 100 to 240 V 50/60 Hz

Power Consumption:  165 W

Dimensions:  474 x 350 x 242 mm (18-3/4" x 13-3/4" x 9-1/2")

Weight:  22 kg (48,4 lbs)


 

Akai X-330D reel-to reel

Stereo Tape Deck with Multi-Purpose Program Minder

The X-330D enables to enjoy different music for 24 hours, in addition to selection and repeating your favourite tune forever.

 


All features:

Program Minder - Automatic Continuous Reverse

Sensing tape continuous reverse. Manual reverse

Cross-field head

3 motors -  A hysteresis synchronous 3-speed motor for capstan drive; Two 6-pole eddy current out rotor motors for supply and take-up reel drive.

3-speed  (7-1/2; 3-3/4; and 1-7/8 ips)

Magnetic brake with tach generator (stoppage occurs within 3seconds from F.F/RWD condition (10-1/2"  reel)

Up to 10-1/2 reel acceptable and back tension control

4-track stereo/monaural recording/playback. For playback the X-330D requires an external power amplifier and speakers

4 heads - Erase, Playback, Record and bias heads

All silicon transistorized pre-amplifier

12 hours continuous hi-fi stereo recording capacity at 1-7/8 ips (7,200 foot tape)

Shield type head for high Signal-to-Noise Ratio

Tape lifter in fast forward and rewind operation

Track selector for simple selection between stereo and monaural

Automatic stop/shut off, Automatic pinch wheel release

Sound on sound, sound with sound, sound over sound

100 kHz biased for FM multiplex recording

Remote controllable, AC outlet with automatic shut off switch

Standard/ low noise tape selector

Tape cleaner, 4-digit index counter with reset button, VU meters

Fine oil finished wooden cabinet

Universal voltage selector ( from 100 V to 240 V, 50/60 Hz)


Marantz Imperial 8 speakers


A Marantz Imperial 8 speaker can handle 125 watts of integrated program material, but reproduces full realism with a fraction of that.

The Marantz Imperial 8 speaker system is just one of two exciting Marantz floor-standing speaker models.

The step-up model Imperial 9 wit tow 10" woofers is designed for higher power handling capabilities as well as high efficiency and mirror imaging. Both models reflect the kind of technical expertise and engineering excellence that has made Marantz the choice of professionals world-wide. Stop by your local Marantz dealer and see the complete line of floor-standing and book-shelf speaker systems starting as low as $59,95

 


Specifications

Frequency Response:  40 Hz to 18,000 Hz ±2 dB (30 Hz to 20,000 Hz ±5 dB)

Sensitivity:  97 dB (1 Watt/0,5 meter, 1 kHz)

Power Rating:  75 watts Continuous (125 watts Integrated)

Distortion Under:  0,5% 100 dB SPL at 0,5 Meter Avg. Of 50/500/5,000/12,500 Hz 2nd and 3rd Harmonics

Nominal Impedance:  8

Dimensions (H x W x D):  27" x 18-3/4" x 14-1/2"