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

Lenco T 30

 The T 30 is a highly sensitive AM/FM tuner which has been developed according to the latest technical knowledge. It is attractive not only because of its modern and professional looking design, but also because of the convenient arrangement of its operating controls. You should read the instructions for use carefully before using it for the first time.
The T 30 is available with either an RCA-phono socket or a DIN socket for connection to the audio frequency signal.

FM Section
Antenna Connections: 
Symetrical : 240 - 300 Ω
Asymetrical : 60 - 75 Ω
Tuning Range:  86 - 109 MHz
Sensitivity (mono,60 Ω-input, 26 dB S/N, Δ f = 40 kHz):  1,8 µV
Limiting Point:  1,5 µV
Distortion, Mono:  ≤ 0,2%
S/N Ratio (Mono, input 1 mV):  ≥ 55 dB
Capture Ratio:  1,5 dB
IF Rejection:  ≥ 90 dB
Image Rejection:  ≥ 80 dB
Frequency Response:  20 - 15,000 Hz
Channel Separation:  ≥ 40 dB
Switching Point:  5 µV
Output (at 1 kHz, Δ f = 40 kHz):  300 mV
AM Section
Tuning Range:  525 - 1650 kHz
Sensitivity (S/N 20 dB):  20 µV
Distortion:  1%
Image Rejection:  ≥ 50 dB
S/N Ratio:  ≥ 50 dB
Power Supply:  AC 220 V 50/60 Hz
Power Consumption:  15 W max.
Dimensions (W x H x D):  430 x 132 x 372 mm
Weight:  7,5 kg

Technics RS-B 905

 Dolby HX Pro-Head Room Extension  System
To record good quality sound, it is necesary to give bias current to the head.  The bias current has characteristics as follows:
Increasing the bias current reduces the distortion in low-frequency range but lowers the recording level in high-frequency renge.
Decreasing the bias current improves the recording level in high-frequency range but increases the distortion in low-frequency range.
In the case of a common deck, a specific level of bias current is determined according to the characteristics of recording head. Therefore, bias current cannot be applied to the head according to the frequency levels of music signal.
In order to solve such problems, this unit employs "Dolby HX-Pro". It picks up the high frequency of music source changing at all times, and controls the bias current level according to the changing frequency. It serves to make the bias current level then most suited for the music source.
This system always operates in recording mode irrespective of the noise reduction system, but the dynamic range in record/playback can be further increased by using this system in combination with a noise reduction system. Particularly, combination with the dbx NR system mounted in this unit will double the MOL (Maximum Output Level) in high frequency range, whi the record/playback of digital source as in CD.
 Record Calibration/Bias Control Function
There are sometimes differences in playback output level even in case of same recording level or in sound quality even in case of same recording source. This is because the characteristics of the cassette tape used are different with the makers and brands.
To solve this problem, RS-B905 is furnished with a record calibration knob and bias control knob.  These knobs can be used to adjust the sound volume and quality while comparing the music signal (original sounds of record and tuner) and recorded signal (sound recorded on tape).
Record Calibration Knob
Used to calibrate the difference in recording level of music signal and recorded signal.
Bias Control Knob
Used to correct the high-frequency sound quality of music signal and recorded signal.
In this way, the record characterisctcs will not be distorted by tape, and the characteristics can be kept nearly uniform.
The comparison by hearing can be done by only one monitor switch because this unit is of 3-head type with record, playback and erase heads.
 MPX Filter
If FM stereo broadcast is recorded by Dolby NR, then the pilot signal included in the broadcast is also processed by Dolby NR as music signal, causing deterioration of sound quality and worsening of noise reduction effect.
Pilot Signal
This signal is used to separate FM broadcast into L and R channels, which is emitted at 19 kHz very close to the music frequency band.
To solve this problem, RS-B905 is equipped with MPX filter switch to cut off the pilot signal.  It serves to cut off the 19 kHz single frequency of the pilot signal, which is different from a high cut filter installed in an amplifier, etc.
Also, MPX filter hardly causes change of sound quality in a sense of hearing.
 Class AA Circuit Recording Equalizer Amp
Recording equalizer amp is an amplifier to supply recording current to the head. Usually, loads such as recording head and bias trap circuit are added to the amplifier. Therefore, the current phase and voltage phase are fluctuated causing the recording signal to be distorted. This unit employs "class AA" amp in which two types of amplifier circuits (voltage control amp and current supply amp) different in ampllifying system. This recording equalizer amplifier is not influenced by the fluctuation of current phase or voltage phase as mentioned above, and is excellent in waveform response.
 Operation Principles of Noise reduction System
Dolby NR, B type, C type
The level of hiss noise generated during playback is constant.  So, it is more offensive to the ear when the music signal level is lower. Accordingly, raising the signal level during recording and lowering the level during playback will result in reduction of noise generated by the tape.  Dolby NR B type does it in high frequency range, and C type, in high and medium frequency range.
Dbx NR
Cassette tape is low in saturation level (limit of recording level). Therefore, distortion will be generated if music signal with large dynamic range (ratio of sound volumes of the weasound and the strongest sound) is recorded as it is.
dbx NR  halves the music signal during recording and doubles it during playback.  In this way, dynamic range as large as 110dB and noise reduction effect as high as 30 dB can be obtained, and good quality sound can be recorded even in case of music source with dynamic range as in CD and live performance.
 Monitor Switch
In order to avoid faulty recording such as low sound level or distortion, it is very important to monitor the state of recording. In the case of a common deck (2-head type), the sound that can be monitored during recording is always the sound before recording. So, when checking the state of actual recording, you have to rewind the tape and play it  back.
Technics RS-B905 is of 3-head type, and the record head is independent of the playback head. Also, the sound before recording can be compared with the recorded sound by use of the monitor switch, therefore the state of recording can be easily checked.

Deck System:  Stereo cassette deck
Track Sysstem:  4-track, 2-channel
Rec/Play : Combination head
Erasing : Double-gap ferrite head
Capstan : Electronically controlled DC motor
Rell Table Drive : Electronically controlled Dc motor
Recording System:  AC bias
Bias Frequency:  85 kHz
Erasing System:  AC erase
Tape Speed: 4,8 cm/sec. (1-7/8 ips)
Frequency Response
Metal : 20 - 22,000 Hz (±15 dB);  30 Hz  - 21 kHz (DIN)
CrO₂ : 20 - 21,000 Hz (±15 dB);  30 Hz - 20 kHz (DIN)
Normal : 20 - 20,000 Hz (±15 dB); 30 Hz - 19 kHz (DIN)
Dynamic Range (with dbx on):  110 dB (1 kHz)
Max. Input level Improvement (with dbx on):  10 dB
Signal-to-Noise Ratio (signal level = max recording level, CrO₂ type tape)
dbx on : 92 dB (A weighted)
Dolby C NR on : 75 dB (CCIR)
Dolby B NR on : 67 dB (CCIR)
NR off : 57 dB (A weighted)
Wow and Flutter:  0,04% (WRMS) ±0,12% (DIN)
Fast Forward and Rewind Time:  Approx. 95 sec.
Input Sensiblity/Impedance
Line : 60 mV/47 kΩ
Output Voltage / Impedance
Line : 400 mV/2,2 kΩ
Headphones ; 125 mV/8Ω
Power Consumption:  25 W
Power Supply:  110 / 120/ 220/240 V AC 50/60 Hz
Dimensions (W x H x D):  430 x 25 x 110 mm (16-15/16" x 11-7/32" x 4-5/16")
Weight:  5 kg (11 lbs)

KLH Model Seven

 The development of the Model Six has served as a valuable source of information for the design and construction of the Model Seven. Believing that a need exists for a loudspeaker system of about this size, the disign staff of KLH began the construction of prototype units using dynamic loudspeakers of various sizes and types. The system which resulted after a number of different units had been made and tested is now in production.
 The low frequency section of the Model Seven is a 12-inch acoustic suspension loudspeaker. The enclosure volume of 2,6 cu. Ft. Permits a very compliant moving system for extended low frequency response.
The high frequency section of the Model Seven consists of two small cone-type direct rediators operating as rigid pistons over a range from 1500 to 20,000 Hz. The use of two such loudspeakers gives a surprisingly large apparent sound source.
The low and high frequency sections are united by an LC crossover network, which establishes the crossover point at 1500 Hz. The relative levels of the low and high frequency section can be varied ±2,5 dB by means of a switch on the back of the enclosure. This provision is made to offer some degree of control over different room acoustics.

Cabinet Size: 24-3/4 x 21-1/2 x 11-7/8 inch (H x W x D)
Volume:  2,6 cu. Ft.
Impedance:  8 ohms
Weight:  52 lbs (shipping)
Finish:  mahogany or oil Walnut

C.E.C. ST-530

 The ST-530 is gracefully slim lines Direct Drive fully  automatic turntable.
Rotation accuracy is a leading feature of the 20-pole 30-slot direct-drive motor which is the heart of this fully automatic turntable. Pushbutton operations are all performed at the front panel and there is no need to lift the dust cover.

Slimlines without acoustic feedback.
A slim cabinet was made possible by special design of the motor and its installation. The independent suspension will not allow button operation to influence platter stability. The sturdy and hefty base plate keeps the motor in position and vibration is not transmitted.

All front operation and fully automatic operation.
Cueing and all other operations are performed from the front panel and there is no need to open the dust cover except to change records. All you need to do is place your favorite record on the platter and push the buttons. Play is then fully automatic ftom cueing to arm return followed by power off.

 Low Mass Straight Tonearm.
The slim, low mass, straight tonearm of this high quality turntable is ideally matched. The pivot head has a horizontal axle and high precision steel ball bearings for the ultimate in smooth operation.

Oil-damped cueing.
Your valuable records can be damaged if the needle strikes the record when it is cued. This is eliminated with oil-damped cueing as the stylus comes to rest in the groove so gently it does not have any impact shock at all.

High cost performance
High performance has been incorporated into this turntable while great efforts were amde to keep cost down. The result is a low cost high performance turntable that can satisfy the demands of the most particular user.

Motor:  20-pole 30-slot 3-phase brushless type DC servo controlled direct drive motor
Sppeds: 33-1/3"  and 45"  r.p.m.
Speed Calibration: Pitch control ±3%
Wow & Flutter:  0,055% (WRMS);  ±0,085% (DIN 45507)
Unweighted : 40 dB (DIN 45539A)
Weighted : 68 dB (DIN 45539B)
Turntable Platter:  308 mm aluminum alloy die-cast with strobe outside rim
Type:  Straight-line tubular, static balence type with removable headshell and antiskating device
Effective length:  222 mm
Overhang:  16,8 mm
Adjustable Tracking Force:  0 -2.5 g with direct readout weight
Usable Cartridge Weight:  4 - 6.5 g
Cartridge  model MM3 (Optional)
Type:  Moving Magnet Type,  0,6mil diamond stylus
Frequency Response:  20 - 20,000 Hz
OUTPUT voltage:  3 mV  ±3 dB at 1 kHz  3.54 cm/sec
Channel Balance:  Within 2 dB at 1 kHz
Channel Separation:  more than 18 dB at 1 kHz
Load Resistance:  47 kohm
Weight:  4,6 g w/ spacer
Optimum Stylus Force:  1,8 g
Automatic start (for 30 and 17 cm records), automatic return, automatic shut off and repeat.
Power Source:  22V 50 Hz for Europe; 120 V 60 Hz for North America
Power Consumption:  6 watts
Dimensions:  416 x 116 x 362 mm
Weight:  5,6 kg

Meridian 508 20-Bit

 The meridian 508 20-Bit CD Player is a unique component that combines major advances in digital audio and engineering design.
 The 508 20-Bit CD Player incorporates a three-beam laser CD mechanism, for superb sound quality and disc playability. The precision-engineered turntable combines the advantages of drawer loading with the superior disc clamping normally associated with top loading players. The digital signal is decoded using the latest 20-bit dual-differential Delta Sigma digital to analogue converter, combined with a discrete class A output for superlative audio performance.


Mechanism:  Three-beam laser.
Conversion:  Dual differential 20-bit Delta Sigma.
Display:  Eight character dot-matrix display for track, time, and index.
THD:  Less than -93 dBFS.
Noise:  Less than -93 dBFS.
Audio output:  2V fixed, class A.
Balanced outputs:  XLR sockets, 1=ground, 2=positive phase output, 3=negative phase output.
Digital outputs:  Co-axial, optical.
Communications:  Two 5 pin 240° DIN sockets.
ConsumptionPower:  20VA.
Finish:  Black textured enamel and glass.
Dimensions:  88mm x 321mm x 332mm (3.46" x 12.64" x 13.07").
Weight:  6.4kg (14lbs).

Dual CT 1740

(German Industrial Standard DIN 45 500 for Hi Fi  stereo home studio equipment)
FM Band : 87,5 - 104 MHz
AM Band : 513 -1602 kHz
FM Mono (75 Ω, S/N ratio 26 dB) : 0,6 µV
FM Stereo(75 Ω, S/N ratio 26 dB) : 1,8 µV
FM Stereo (75 Ω, S/N ratio 46 dB) : 18 µV
AM (according to DIN 45 300, S/N ratio 6 dB) : 15 µV
Automatic Mono/Stereo Switchover Adjusting Range:  10 - 280 µV
Mutin Control (can be switched off, variable range):  10 - 230 µV
Limiter Operating Point -3 dB:  0,5 µV
Signal-to-Noise Ratio (weighted)
Mono (related to 1 kHz /40 kHz deviation) : 63 dB
Stereo (related to 1 kHz/46 kHz deviation) : 63 dB
Signal-to-Noise ratio (unweighted)
Mono (related to 1 kHz/40 kHz deviation):  60 dB
Stero (related to 1 kHz/46 kHz deviation):  60 dB
Pilot-tone-attenuation (measured via low-pass filter):  65 dB
Harmonic Distortion
Mono (measured 1 kHz/4 kHz deviation) : 0,3%
Stereo (measured 1 kHz/4 kHz deviation) : 0,3%
Channel Separation (at 1,000 Hz):  40 dB
Af Frequency Response (for 50 µs preemphasis -1,5 dB):  20 hz - 15 kHz
IF Bandwidth -3 db:  140 kHz
Selectivity:  85 dB
Image Rejection (Fe + 2 ZF):  75 dB
Spurious Signal Rejection (Fe + ZF₂):  100dB
FM : 60/75 and 240/300 ohm impedance
AM : High impedance (inductive)
Dimensions (W x H x D):  40 x 150 x 365 mm
Weight:  7,8 kg

Marantz model 1072

Audio Section
Power Output (DIN Standards, 4 ohm):  77 W per channel
Power Output (FTC American Standards, 4 ohm):  46 W per channel
Total Harmonic Distortion:  0,08% (at rated output)
I M Distortion (250 Hz and 8 kHzMixed, Amplitude Ratio 4:1):  0,08% (at rated power output)
Power Output (DIN Standards, 8 ohm):  50 W per channel
Power Output (FTC American Standards, 8 ohm):  36 W per channel
Total Harmonic Distortion:    0,05% (at rated output)
I M Distortion (250 Hz and 8 kHz Mixed, Amplitude Ratio 4:1):  0,05% (at rated power output)
Power Bandwidth:  15 Hz ~ 60 kHz
Damping Factor (8 ohm):  45
Frequency Response:
Phono (RIAA) : ±0,5 dB
Aux : 15 Hz - 60 kHz (±1 dB)
Phono Input Terminal:
Impedance : 47 kohms
Capacitance : 100 pF
Sensitivity : 2,0 mV
Overload Margin : 35 dB
Aux Input terminal:
Impedance : 25 kohms
Sensitivity : 180 mV
Phono Equivalent Input Noise:  0,5 µV
Phono Dynamic Range (Ratio of input overload to equivalent input noise):  100 dB
Channel Balance (0 to -40 dB/40 Hz - 16 kHz)
Phono : 3 dB
Aux : 3 dB
Interchannel Crosstalk (at 1 khz):
Phono : 47 dB
Aux : 62 dB
Tape : 62 dB
Intersource Crosstalk (Worst Point), 1 khz:  55 dB
Tape Output Voltge/Impedance, 1 kHz : 775 mV/220 ohms
Headphone Jack load Impedance:  4 ohms
General Section
Power requirements:  110 / 120 / 220 / 240 V AC, 50/60 Hz
Power Consumption (at rated output, both channel driven):  160 W ±20 W
Idling Power:  14 W ±5 W
Semiconductor Complement:
Transistors : 45
Diodes : 26
Dimensions (W x H x D):  416 x 146 x 240 mm (16-3/8" x  5-3/4" x  9-7/16")
Weight (net):  8 kg (17,6 lbs)

Philips AF 777

 Automatic Hi-Fi Stereo Turntable with Direct Drive
Shock-proof free-floating sub-chassis
Straight tubular-aluminiumtonearm with de-coupled adjustable counterweight
Very low-friction tonearm bearings
Light detachable headshell
Automatic diameter selection and positioning of arm on start of record.
Automatic stop, arm lift and return at end of record.
Hydraulically damped arm lift
Anti-skating adjustment for spherical and elliptical styli
Direct readout of stylus force.
Controls for 33 and 45 rpm, Start and Stop.
Pitch controls with 3-LED-bar actual speed indication
Attractive tinted dust cover with friction hinges.
 The AF777 has a high standard of performance. Rumble, for example, is better than -65 dB (DIN B), and wow and flutter is less than 0,05% (weighted rms).These very good figures are attributable to the thorough design and construction of the various sub-sections of the turntable; the suspension, tonearm, headshell, and especially the Direct Control electronics which regulate so precisely the speed of the turntable.

To ensure that the record always rotates at exactly the right speed, the rate of rotation of the turntable itself is continuously monitored and regulated by the Direct Control electronics. The turntable, which is belt-driven from a separate Dc motor, has a tachometer built into it. The output of the tachometer is accurately converted into a d.c. voltage whose level is proportional to the actual speed of the turntable. This signal is continuously compared with a stable d.c. reference signal. If anything tends to alter thr turntable speed the tacho-derived signal will differ from the reference; this difference causes the Direct Control electronics to immediately accelerate or slow down the drive motor sa as to correct the speed of the turntable.

In addition to improving rumble, wow and flutter and drift specifications, direct control of the turntable speed has the important advantage that the record speed is unaffected by external influences such as the drag ofa cleaning device or different stylus force. Similarly, the Direct Control electronics compensate for fluctuations in temperature or line voltage and frequency.
Top Quality Tonearm
The straigh tubular-aluminium construction of the tonearm gives it an ideal combination of lightness, strength and rigidity, mechanical properties sa vital to a top quality tonearm. Because it is straight, with the stylus on its longitudinal axis, and since the aluminium headshell is so liht, the tonearm's centre-of-gravity lies very close to its axis. Consequently, torsional forces on the arm are minimal. This helps to eliminate unwanted high frequency resonances and keeps the natural resonance of the arm, with the cartridge, to an acceptable low frequency.De-coupling of the tonearm's counteweight provides wideband damping.

Low Friction Bearings
Horizontal and vertical friction forces in the bearings have been reduced to an exceptionally low value (better than 15 mg), so that there is almost no resistance to movement of the arm. As a result, the stylus is aable to faithfully follow even the most delicate modulations in the record groove.
 Minimal Tracking Error
Geometric characteristics of the tonearm, such as offset angle and location of the stylus on the tonearm's axis, have been designed to minimise tracking error (better than 0°9'/cm)

Excellent Trackability
The exceptionally small tracking error, combined with very low bearing friction, ensures the excellent trackability characteristics of the tonearm. This is one tonearm which allows full advantege of the trackability of the chosen cartridge.

Free-floating Sub-chassis
The turntable and tonearm assemblies  are mounted on a separate sub-chassis which is suspended from the main chassis via three nickel-chromium leafsprings with butyl-ruber dampers. This free-floating sub-chassis type of suspension is a wellprvoen and extremely effective technique that achieves superb mechanical isolation of  the turntable and tonearm from the main chassis.

Rumble-free, shock-proof and protects record and stylus
The mechanical isolation of the turntable and tonearm has been further improved by careful lacation of the springs and by using material with the best possible damping properties. Suspension of teh motor from the main chassis has also helped improve isolation. The result is that rumble from the motor is virtually eliminated, and external disturbances, such as vibration and acoustical feedback are not transferred to the cartridge. Even quiete violent knocks to the outer casing will not cause unwanted acoustical noises. And, the valuable stylus and records are better protected from accidental damege.

Turntable Speeds:  33 and 45 rpm
Wow & Flutter:  better than 0,08% DIN ( better than 0,05% weighted rms)
Rumble: better than -43 dB (DIN A); better than -65 dB (DIN B)
Pitch Control Range:  ±3%
Speed Indication:  3-element LED-bar
Tonearm Type:  Tubular-aluminium
Tracking Error:  Better than 0°9'/cm
Bearing Friction:  Better than 15 mg, vertically and horizontally
Resonant Frequency:  10 Hz (with test cartridge)
Effective Arm Length:  215 mm (8½ inches)
Effective Moving Mass:  16,5 g
Anti-skating Adjustment:  For spherical and elliptical styli
Cueing Lever:  Hydraulically damped
Headshell:  Die-cast aluminium
Stylus Force: 
Range : 0 -3 gf
Indication:direct readout
Material : aluminium
Diameter : 320 mm approx.
Power Supply:  110 V, 60 Hz ; 220 -240 V 50/60 Hz
Current Consumption:  0,1 amperes
Dimensions (W x H x D): 
Dust cover closed : 420 x 141 x 348 mm (16½" x 5½" x 13¾")
Dust Cover Open : 420 x 335 x 385 mm
Weight:  5,8 kg (12,8 lbs)

Acoustic Research AR-2a

 The Acoustic Research AR 2a 3-way system loudspeaker
Two 5" Cone units for Sparkling Midrange
Hemispherical Super-Tweeter
Thunderous  "Lows"
Glittering "Highs"
Acoustic Suspension, The concept which expanded the horizons of high fidelity by creating new standards of bass response and low harmonic distortion, is utilized in this moderately-prieced 4-speaker system. The 10" woofer is essentially flat to 42 cps (-10 dB at 30 cps). Harmonic distortion at 40 cps is a mere 3%. Two 5" cone units in dispersed array range from 2000 to 7500 cps. The unique AR Super-Tweeter raises the response beyond 20,000 cps. This hemispherical radiator is without rival for smoothness, low dispersion characteristics and virtually flawless transient response. As a result, the AR2a has received accolades and applause from audio experts and won renown for setting new standards of excellence in its field. The size of theenclosure is dictated by Acoustic Suspension; the air-sealed cabinet providing  a pneumatic spring for most of the cone-restoring force, rather than convential mechanical springing.
Midrange and HF units independently adjustable.

Drive Units
1 x 1,375" dome tweeter
2 x 5" cone midrange
1 x 10" cone woofer
Impedance:  8Ω
Frequency Respnse:  42 to 20,000 cps (Hz)
Crossover Frequency:  2000, 7500 cps (Hz)
Amplifier Power:  20 watts minmum
Size:  13½"(H) x 24"(W) x 11½"(D)
Weight:  41 lbs
Finish:  Mahogany, Birch, Walnut, Oiled Walnut
Price:  $128,00

McIntosh MR 7083

 The Mclntosh MR 7083 is a high quality AM/FM Tuner whose design has been governed by insistence on high performance with long life, great flexibility and sensitivity. You will derive the greatest enjoyment and most satisfaction from your MR 7083 when you understand its operations and functions. Your time invested now will return added value to you because you will get the best results from your MR 7083. Mclntosh has earned world renown for its technological contributions for improved sound. When you bought Mclntosh, you bought not only high technology, you bought technological integrity proven by time. The Mclntosh MR 7083 Tuner is continuing evidence of Mclntosh technological superiority and integrity.
Music reproducing instruments that carry the Mclntosh name have always been designed for technological leadership and to maintain the Mclntosh reputation for durability, long life, and best sound. Mclntosh has had to earn the foremost reputation for quality performance. Mclntosh has provided user-oriented facilities and appearance, and Mclntosh design provides for ease of maintenance or repair. These fundamental elements are incorporated in the Mclntosh MR 7083 AM/FM Tuner, the easiest to operate yet with extensive useful features. Your Mclntosh MR 7083, above all others, will deliver the best sound and the greatest ease of use with a high degree of flexibility.
 Some of the features that set the MR 7083 apart from the ordinary are:
The advanced AM/FM tuner design of the MR 7083 displays the station frequencies digitally. Stations are selected easily in any one of these ways:
A. use the manual tuning knob, B. use the SCAN up or down touchbuttons, C. use the preset station touchbuttons or, D. use the SEARCH which will preview the preset stations for 5 seconds each.
The sound enhancing SPATIAL audio processor provides an aural picture that is more "stereo like" in quality and dimension. On noisy, weak FM stations or AM stations, SPATIAL provides reduced noise and retains a broad stereo-like sound.
High quality tape recordings of FM broadcasts can be made without the interference that stereo transmissions can cause. Carefully designed suppression circuits eliminate the potential for stereo carrier noise when making "off the air" tape recordings.
A unique Phase Locked Loop Multiplex decoder delivers STEREO FM with lower distortion, lower noise, and better separation.
The most useful and flexible AM antenna system will suit your particular installation. A low-impedance loopstick will, in most local areas, provide AM signals while rejecting noise and interference. In noisy AM locations, an external noise reducing, noise canceling, shielded loop will provide ideal input signal. In a remote location, a conventional 'long wire' antenna can be used.
The MR 7083 can be remote controlled from a Mclntosh IR Remote Control system.
All in all, your selection of the MR 7083 will be reinforced by your day-to-day use of this superb instrument. Good listening.
Preset stations 
16 station memory presets are available 8 for AM and 8 for FM stations. preset memory is retained even when AC power is turned off
Three Modes of Tuning 
A traditional tuning knob as well as a push button scan and preset buttons are provided.
Digital Display 
Exact digital display of tuned frequency.
Center Tuning Lock 
Each time a frequency change takes place it locks on the center of the channel.
Auto Muting 
Automatic muting when changing stations.
Solid State Tuning Indicators 
9 LED Signal strength bar indicates signal strength. 3 LED signal centering display allows for precise center tuning ,
Versatile Outputs
Both fixed and variable audio outputs included
DMOSFET RF Amplifier 
Double Balanced Mixer and 4 RF circuits that are tuned by matched varactor diodes. The results are high spurious rejection and great sensitivity. This circuitry and high tuning voltage eliminate RF inter modulation distortion caused by diode nonlinearities. stations
FM IF Section 
The FM IF section uses 2 transistors, 3 linear phase piezoelectric filters, and 2 integrated circuits. They combine to provide over 120dB of gain and a selectivity greater than 70dB. Limiting, muting, signal strength drive, and FM detection are all functions of the LA 1235 integrated circuit..
Phase Locked Loop (PLL) Stereo Decoder 
A phase locked loop (PLL) stereo decoder integrated circuit, the TCA 4500A, is the heart of the multiplex section. It has a high signal to noise ratio, low distortion, high channel separation, and high SAC rejection. The PLL MPX IC eliminates inductors to minimize drift, provides integral lamp driving capability for stereo indication, and has transient free mono/stereo switching.
LC Tuned Notch Filter 
Following the PLL MPX decoder an LC tuned notch filter is used to prevent tape recorder bias interference. The LC filter is driven from the MPX output amplifier and is terminated by an operational amplifier. This provides the necessary filter input and output impedances for proper phase response.
Display Provisions 
Scope outputs allow an oscilloscope to be connected for viewing FM Multipath, station signal strength and center tuning accuracy.

USABLE SENSITIVITY:  11.25 dBF which is 1.0 μV across 75 ohms
Mono : 15 dBF which is 1.6 μV across 75 ohms
Stereo : 37 dBF which is 20 μV across 75 ohms
Mono : 80 dB
Stereo : 75 dB
Mono :  from 20 to 15,000 Hz (+ 0, -1dB)
Stereo :  from 20 to 15,000 Hz (+0, - 1dB)
Mono :
0.08% at 100 Hz
0.08% at 1000 Hz
0.12% at 10,000 Hz
Stereo :
0.08% at 100 Hz
0.08% at 1000 Hz
0.12% at 10,000 Hz
Mono : 0.08%
Stereo : 0,12%
SENSITIVITY:  AM 20 μV external antenna input (50 ohm source input)
50 dB at 30% modulation
60 dB at 100% modulation
HARMONIC DISTORTION:  0.5% maximum at 30% modulation
IMAGE REJECTION:  78 dB minimum
Fixed:  1.2 V RMS at 100% modulation
Variable:  1.2 mV to 1.2 V at 100% modulation
Transistors 37
Integrated Circuits 28
Varactors 8
LEDs 53
Diodes 74
DIMENSIONS (W x H x D):  406 x 138 x 330 mm (16-1/8" x 5-7/16" x 13") from the mounting surface, including PANLOC shelf and back panel connectors. Knob clearance required is 1-1/4 inches (3.2 cm) in front of the mounting panel.
Front panel is glass with special gold/teal nomenclature illumination and black with gold anodized aluminum. Chassis is black.
Exclusive Mclntosh developed professional PANLOC
WEIGHT:   7.0 kg (15½ pounds) net;  12.5 kg (27½ pounds) in shipping carton

Luxman L-525

 Status Series Duo-β Single-Stage Stereo Integrated Amplifier Luxman L-525 (1981)
High Dynamic Power
What is crucial with an amp is whether or not it can feed such quality power that satisfactorily drives the loudspeaker having inherently complex, non-linear impedance characteristics. With overall reinforcement especially at the output and power supply sections, the L-525 provides an unprcedented high dynamic power for absolutely stable operation even into low impedance loads such as 4 and 2 ohms. Furthermore , an ideal class "A" operation is procured up to a normal listening level.

High Quality Power to Exhibit Its Real Value at Low Output Level
Truly high-quality power quite contrary to that unaccompanied by intrinsic quality and merely stated "high" in the specs. Such affluent 110W + 110W provide not only instant, treal-time response to the sharp, abrupt rise of the large signal input but vivid sound image at a low volume level.

Tone Control to Offer Smooth, Natural Variation Response.
With 6 turnover frequencies at each of the treble and bass ranges, you can create your favourite response curve most natural in auditory sensation.  Noises and other sonic deterioration are skillfully prevented thanks to the NFb circuitry of the power amp section.

 EQ to Take out Full Advantage of MC Cartridge
A highly dependable symmetric differential push-pull equalliser by means of high gm, low-noise FET exclusively Developed for MC headamp offers superb sonic quality with high S/N and low distortion, which makes it possible to take out the full potential of the MC cartridges on the marketplace by simple, direct connection.

Affluent Power Supply.
The mighty power supply section composed by the EI core transformer of large capacitance and large smoothing chemical capacitors provides instant large current in low impedance.

Convenient Warm-Up Indicator
In a certain lapse of time after the power is turned on, the warm-up indicator goes out to show that the amp is put into an operational condition.

Perfect Compliance with Digital and Analogue Source.
Both of the analogue and digital sources are granted with their own personality in characteristics. To cope with the sublime treble recording characteristics of analogue disc, the linearity of the head amp (L-560) and the equaliser amp (L-525) are dramatically ameliorated, whereas to comply with the ultra wide dynamic range of CD source, the power amp is substantially solidified to reproduce the ultra heavy bass in an explosive way.

Power output:  110 W +110 W at 8Ω (both channels driven, 20  - 20,000 Hz)
Dynamic Power:  230 W at 4Ω
T.H.D.:  no more than 0,007% (8Ω, 20 - 20,000 Hz, -3 dB)
Rated IM:  no more than 0,007% (8Ω, -3 dB, 60 Hz:7 Khz = 4:1)
Input Sensitivity & Impedance:
Phono MM:  2 mV/50 kΩ
Phono MC:  100μV/40Ω, 100Ω, 300Ω
Tuner, Line, CD:  150 mV/40 kΩ
Main-in:  150 mV/47 kΩ
Signal-to-Noise ratio (IHF-A weighted):
Phono MM:  better than 85 dB (input 5 mV)
Phono MC:  better than 70 dB (input 250μV)
Tuner, Line, CD:  better than 110 dB (input short-circuited)
Frequency Response:
Phono MM/MC:  20 - 20,000 Hz,  ±0,3 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:   77 Hz, 120 Hz, 200 Hz, 330 Hz, 550 Hz, 880 Hz
Treble turnover frequencies:  880 Hz, 1.5 kHz, 2.5 kHz, 4 kHz, 6.5 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  switch;
Signal-off switch; Tone-in switch; Recording switch; Tape monitor and tape dubbing;
Speaker selector, etc.
Dimensions (W x H x D):  453 x 162 x 470 mm
Weight:  14,3 kg