Optonica ST-3535 tuner

Outstanding Features

Multipath Detector Circuit

The ST-3535 incorporates a meter and terminals for an oscilloscope to detect multipath distortion and a built-in circuit to monitor its composition. The degree of multipath distortion is indicated by the meter, by the sound volume or by the waveform on the oscilloscope. Therefore, the antenna direction is easily and accurately reset. The circuit also improves FM listening and assures optimum recording.

Built-in Air Check Calibrator

This is a unique device for accurate "FM Air Check". Just flip on the switch and a level signal equivalent to that of the FM signal is generated. Then all you have to do is set the recording level to 0 VU on the deck.

Monolithic ICs are employed, Inter-station noise is eliminated by the muting switch

A hi-blend switch to reduce noise during reception of weak FM stereo signal

Variable audio output level control

Signal strength meter - this meter responses in proportion to the degree of signal intensity, thereby rendering effortless tuning under any condition

Easy-to-read-and-tune FM linear dial with a frequency-linear type variable capacitor, 8-11/16" wide scale, large flywheel and smooth tuning mechanism

FM signal input attenuator reduces distortion due to high signal input levels for stable FM reception

The FM antenna is equipped with dual terminals for 300 ohms or 75 ohms

Composite signal output terminal is provided for future possible FM 4-channel broadcasting

 

Outstanding Performance

Dual-gate MOS FETs and FM front end equipped with 4-gang linear tuning capacitor

The FM front end consists of a 4-gang capacitor that employs a double-tuned RF amplifier stage and a mixing stage. Remarkable performance characteristics such as 2,5 µV IHF sensitivity. 80 dB spurious response rejection ratio and 85 dB IF rejection ratio are attained. These figures assure high sensitivity and stable reception.

IF stage designed for high selectivity and interference protection

To obtain both ultra-low distortion characteristics and high selectivity, a phase linear ceramic filter and differential IC circuit are employed to make the phase characteristics at the IF stage linear. The band pass characteristics is also greatly improved.

PLL MPX circuitry

The PLL (phase-Locked Loop) circuit replaces the conventional coils and associated components with ultra-reliable integrated circuitry. The PLL circuit automatically compensates for phase-shift, thus ensuring stable separation for long periods of use.

A sub-carrier trap with inductive M-type filter is employed

 

Specifications

FM Section

Frequency Range: 87,6 - 108 MHz

Antenna Input:  75 Ω  (unbalanced); 300 Ω  (balanced)

Sensitivity (IHF)

Mono :  2,5 µV (300 Ω  antenna terminal)

Image Rejection:  80 dB

IF Rejection:  85 dB

Spurious Response Rejection:  80 dB

AM Suppression:  43 dB (mod. 30% AM by 1 kHz and 100% FM by 400 Hz)

Capture ratio:  1,5 dB

Selectivity:  65 dB (±400 kHz, 65 kHz Dev.)

Signal-to-Noise Ratio

Mono :  65 dB (75 kHz  Dev. 1 kHz)

Total Harmonic Distortion

Mono :  0,4% (75 kHz  Dev. 1 kHz)

Stereo :  0,8% (75 kHz  Dev. 1 kHz)

Stereo Separation

34 dB :  1 kHz, 75 kHz Dev.

25 dB :  50 Hz - 10 kHz

Frequency Response:  45 Hz - 13 kHz (±1,5 dB)

AM Section

Frequency Range:  520 - 1620 kHz

Antenna:  Built-in ferrite loopstick antenna AM external antenna terminal

Sensitivity:  400 µV /m (IHF, ferrite antenna)

Selectivity:  25 dB (at 1,000 kHz)

Signal-to-Noise Ratio:  35 dB

Image Rejection:  55 dB (at 600 kHz)

Total Harmonic Distortion :  1,5%

Audio Section

FM Output

Fixed :  0,5 V (1 kHz, 75 kHz Dev.)

Variable :  0 - 1,0 V (1 kHz, 75 kHz Dev.)

A Output

Fixed :  0,15 V (30% Mod.)

Variable :  0 -0 ,3 V (30% Mod.)

Composit Signal Out Terminal:  Yes

General

Semiconductors:  2 MOS FETs; 5 ICs plus 1 aux IC; 10 Transistors plus 16 aux Transistors; 6 Diodes plus 15 aux Diodes

Power Requirements:  AC 120 50/60 Hz

Power Consumption:  24 W

Dimensions (W x H x D):  17-3/8" x 5-5/8" x 15"

Weight:  2 lbs

 

Toshiba ST-500 tuner

AM / FM Stereo Tuner

4-gang tuning condenser and dual gate 4-pole FET's in FM front end

Ceramic filters and two ICs consist of differential amplifier limiter in FM IF circuit

Linear, wide-scale dial, and two tuning meters, and AFC on/off switch, and FM muting circuit

RF amplification, double stage AGC and ceramic filter for low distortion and high AM sensitivity and for normal operation opposing strong signals

High-blend switch and manual FM/FM-stereo switch for improving Signal-to-Noise Ratio at weak FM stereo signal

Output terminal for future FM 4-channel broadcasting

Natural walnut cabinet

 

Specifications

FM Section

Tuning Range:  88 - 108 MHz

Intermediate Frequency:  10,7 MHz

Sensitivity:  1,8 µV (IHF); 1,8 µV (S/N=30 dB)

Signal-to-Noise Ratio :  66 dB

Capture Ratio:  1,5 dB

Selectivity:  80 dB (IHF)

Image Rejection:  80 dB

IF Rejection:  80 dB

Spurious rejection:  100 dB

AM Suppression:  50 dB (IHF)

Frequency Response:  20 - 15,000 Hz ±1 dB

Antenna:  300 Ω  (balanced); 75 Ω  (unbalanced)

Harmonic Distortion

Mono :  0,2% at 400 Hz (100% mod.)

Stereo :  0,5% at 400 Hz (100% mod.)

FM Stereo Separation:  better than 35 dB at 1,000 Hz

19 kHz, 38 kHz Suppression:  50 dB

AM Section

Tuning Range:  530 - 1605 kHz

Intermediate Frequency:  455 kHz

Sensitivity:  15 µV (IHF)

Signal-to-Noise Ratio:  45 dB

Image Rejection:  70 dB

Selectivity:  30 dB (±10 kHz)

IF Rejection:  70 dB

Overload:  2 V/m at 1,000 kHz

Harmonic Distortion: 1%

General

Circuit:  Superheterodyne [AM & FM] 2 ICs ; 3 FET's; 23 Transistors; 23 Diodes

Power Source:  AC 100/120/220/240 V ; 50/60 Hz

Power Consumption:  25 W

Output Level:  600 mV (fixed, 100% modulation) 0 - 2 V (variable)

Dimensions (W x H x D):  400 x 125 x 333 mm ( 15-3/4" x 4-7/8" x 12")

Weight:  5,6 kg (14-5/16")

Accessory:  FM feeder antennas, connecting cord, polishing cloth,

 

Tandberg TR-1040 receiver

The FM Receiver

The FM receiver has MOSFET transistors giving good reception for weak and strong stations. Extra linear phase response and high selectivity with 4-pole ceramic filters. A good performance is obtained from the integrated IF amplifier and detector. The FM stereo decoder has integrated circuits that include a phase-locked-loop oscillator giving good channel separation over the complete frequency range. The stereo decoder has automatic or manual change-over between mono and stereo. Active filters remove the stereo systems pilot tone and auxiliary carrier wave. Precise tuning is easy with the two large tuning meters, a big advantage, especially with stereo transmissions. The FM receiver is equipped with a muting circuit that removes inter-station noise.

 

Power amplifier

The amplifier has been designed to handle extremely heavy loads. Automatic protection circuits keep watch over it constantly. tR-1040 has a direct coupled, short-circuit proof output stage. Complementary output transistors give very low distortion. An electronic controlled relay protects the loudspeakers from accidental d.c. damage. Automatic thermal protection disconnects the amplifiers if they are overheated (from bad ventilation) and connects them again immediately the temperature has fallen.

 

Pre-amplifier

The pre-amplifier is designed for a transcription unit or record player with a magnetic pick-up. All the inputs are adjustable. Three effective filters (1 Low and 2 High) attenuate disturbing noise from program sources. An extra refinement is the separate bass and treble controls for each channel which permits equalization for bass and treble differences resulting from asymmetrical positioning of loudspeakers.

 

Specifications

Audio Section

Power Output:  average continuous sinewave power is 40 watts minimum rms per channel, both channels driver into 8 ohms load, from 20 to 20,000 Hz with no more than 0,2% t.h.d from 1/4 watt to 40 watts as specified herein.

Total Harmonic Distortion :maximum 0,2% at any power from 1/4 watt up to rated power.

Intermodulation Distortion:  0,2%

Damping Factor:  50 at 8 Ω , 20 - 20,000 Hz

Frequency Range:  Linear inputs from 7 to 70,000 Hz (-1,5 dB)

Controls

Treble :  ±15 dB at 10,000 Hz

Loudness Comp. : +7 dB at 10,000 Hz

Bass :  ±16 dB at 50 Hz

Loudness Comp. : +12 dB at 50 Hz

Low Filter:  -3 dB at 70 Hz (-12 dB /oct.)

High Filer 1 :  -3 dB at 8000 Hz (-12 dB/octave)

High Filter 2 :  -3 dB at 8000 Hz (-6 dB /octave)

Channel Separation: 

Phono :  52 dB (at 1 kHz)

Tape :  56 dB (at 1 kHz)

Signal-to-Noise Ratio (IHF)

Phono :  68 dB

Tape 1, 2 :  82 dB

Sensitivity:

Phono :  1,8 to 6,0 mV

Tape 1, 2 :  130 to 500 mV

Main Amplifier Sensitivity:  200 mV

Input Impedance :  10 k Ω

Outputs

Tape 1 and Tape 2 Outputs (Unloaded)

DIN Socket :  200 mV

Phono Socked :  1 V

Pre-Amplifier Output:  1 V / 1 k Ω 

FM Section

Tuning Range:  87,5 to 108 MHz

Sensitivity IHF:  2,0 µV at 300 Ω

50 dB Quieting:  3,5 µV at 300 Ω

Selectivity:

Carrier down (alternate channel) 100 dB at ±400 kHz

IHF Dynamic (alternate channel) 80 dB at ±400 kHz

Carrier Down  (adjacent channel) 40 dB at ±200 kHz

IHF Dynamic  (adjacent channel) 10 dB at ±200 kHz

Spurious Response:  better than 95 dB

Capture Ratio (at 1 mV ant. volt, selectively measured):  0,9 dB

Total Harmonic Distortion (at 100% modulation)

Mono :  0,2%

Stereo :  0,3%

Channel Separation (at 100 Hz to 10,000 Hz, selectively measured):  better than 40 dB

Pilot Tone Suppression: better than 68 dB

38 kHz Suppression:  better than 60 dB

SCA Suppression: better than 70 dB

General:

Main Voltage:  120 V (Internal Connections for 120/220/240 V ) 50/60 Hz

Dimensions (W x H x D):  440 x 132 x 310 mm (17-1/2" x 5-3/16" x 12-1/4") + knobs 20 mm (3/4")

Weight:  9 kg (20 lbs)

 

Rotel RX-802 receiver

We've the fine wood-grain cabinet off of the RX-802 to give you a perfect picture of what performance in a high-quality AM/FM stereo receiver looks like. So see for yourself. It's all here. A masterful blend of the very latest circuitry. Low-noise, long-life silicon transistors integrated circuits. An AM/FM front end that's out front in sensitivity and performance. A power amplifier section that's - well, we'll let you decide for yourself what it is after hearing the giant 6,800 mfd block capacitors in action. And an advanced NF and IC equalizer amplifier. This and more, all within the good looking RX-802 enclosure. And all there for one reason. To give you the most satisfying experience in stereo dynamics that you've had to date. Inside and out, the RX-802 is not only the sweetest looking receiver on the music market, it's the sweetest sounding sweetest looking.

 

The performance begins here

With a high-performance, high-sensitivity FM front end. The RX-802 has dual-gate MOS FET's and a 4-gang linear-frequency tuning capacitor, the latter largely contributes to sensitivity and performance which you will translate directly into musical enjoyment. If you.ve thought all along that all receivers were basically the same, you'll stop where RX-802 performance begins.

 

FM IF and AM IF sections

In the FM IF section, 2 high-gain ICs housing 6 differential amplifiers and two linear-phase ceramic filters get together to achieve brilliant selectivity and rejection characteristics. In the AM IF section, a hard working ceramic filter provides equally efficient selectivity. Together with an RF stage in the AM front end, the sum of RX-802 AM features is performance that perks up all ears, no matter how tired.

 

A tower of power

A stable, split-power supply high-lights the amplifier section, which includes to 6,800 midblock capacitors and an oversized power transformer. That's a lot of satisfaction. It's also a lot of power which the RX-802 maintains constantly. This section also has directly-coupled OCL complementary circuitry to keep the power up and the distortion down, from one end of the audio spectrum to the other - 50 watts per channel, min. RMS, both channels driven simultaneously into 8 ohms from 20 to 20,000 Hz with no more than 0,5% Total Harmonic Distortion. And "steady she goes" doesn't only apply to ships. Now it describes the dampening factor and output characteristics which achieve superb transient response throughout the very low frequency range.

 

NF and IC equalizer amplifier

Genuinely outstanding RIAA characteristics are achieved through low-distortion, directly coupled NF (negative Feedback) circuitry combined with high voltage IC. Reproduction is more transparent than ever before. And added bonus is that tone control circuitry benefits from the same directly coupled NF circuitry.

 

PLL MPX section

Phase Lock Loop integrated circuitry and other new circuitry innovations in the MPX section result in improved stereo separation and frequency response. Distortion goes way down and stays there.

 

Specifications

Amplifier Section

Continuous Power Output (min. RMS)

50 watts per channel, both Channel Driven into 8 Ω  from 20 to 20,000 Hz with no more than 0,5% t.h.d

60 watts per channel, both Channel Driven into 8 Ω at 1 kHz with no more than 0,5% t.h.d

Harmonic Distortion:  less than 0,05% (8 Ω , 1 kHz, 90% rated power)

Intermodulation Distortion :  less than 0,15% (8 Ω , 90% rated power)

Power Bandwidth (IHF):  5 to 50,000 Hz (8 Ω )

Frequency Response:  10 to 100,000 Hz ±3 dB, 1W/1W

Damping Factor:  40 (8 Ω , 1 kHz)

Input Sensitivity/Impedance:

Main IN :  100 mV/ 34 k Ω

Tape Monitor :  140 mV / 26 k Ω

Aux 1, 2 :  140 mV / 26 k Ω

Phono 1, 2 :  2,4 mV / 40 k Ω

Tape Output Level:  280 mV/ 1,7 k Ω

Phono Overaload:  150 mV (1 kHz)

Phono Equalization:  RIAA standard ±0,5 dB

Controls

Bass :  ±10 dB at 100 Hz

Treble :  ±10 dB at 10 kHz

Loudness Contour:  ±6 dB/100 Hz +4 dB/10 kHz

Crosstalk:  50 dB / 10 kHz

Hum and Noise (Continuous Power Output)

Phono :  65 dB

Tape :  80 dB, Residual 0,5 mV

Speaker Impedance:  4 to 16 ohms

FM Tuner Section

Frequency Range:  88 to 108 MHz

Sensitivity (IHF):  1,5 microvolts

Signal-to-Noise Ratio :  70 dB

Harmonic Distortion: 

Mono :  0,2%

Stereo :  0,4%

Selectivity:  80 dB ±400 kHz

Capture Ratio:  1,0 dB

Stereo Separation:  40 dB at 100 Hz, 40 dB at 1 kHz, 35 dB at 10 kHz

IF Rejection:  100 dB

Image Rejection:  100 dB

Spurious Response Rejection:  100 dB

SCA Suppression:  70 dB

AM Suppression:  55 dB

AM Tuner Section

Frequency Range:  520 to 1650 kHz

Sensitivity:  15 microvolts

Selectivity:  50 dB ±10 kHz

IF Rejection:  80 dB

Image Rejection:  80 dB

Signal-to-Noise Ratio:  55 dB

General

Power Requirements:  AC 100, 120, 220, 240 V, 50/60 Hz

Power Consumption:  450 W max

Dimensions (W x D x H):  24" x 15" x 5-3/8"

Weight:  13,5 kg (35,2 lbs)

 

JBL 4430 monitor loudspeakers

Developed to meet the challenge of digital and advanced analog recording technology, the JBL Model 4430 {and Model 4435} represent a significant new approach to two-way studio monitor design. The incorporation of the unique JBL Bi-Radial ™ horn in a monitor loudspeaker provides constant vertical and horizontal polar coverage, control of the reverberant field, flat power response, image stability, and coherent sound. The two models also feature improvements in compression driver, low frequency transducer, and dividing network technology. Both systems exhibit the traditional )BL attributes of wide bandwidth, smooth frequency response, high efficiency, wide dynamic range, and exceptional reliability.

The practical benefits of the Bi-Radial monitors include stable stereo imaging that remains fixed over a wide range of horizontal positions, the result of unusually smooth off-axis response. The design allows considerable latitude in physical placement. The wide vertical response, identical to the horizontal, includes both standing and seated listeners within the coverage angle, even in proximity to the monitors.

 

THE JBL BI-RADIAL ™ HORN

The Models 4430 offer performance levels normally achieved by three- and four-way systems. The key to this performance is the JBL Bi-Radial ™ horn 1 and its integration in a monitor design.

Most horn designs compensate for the failing power response of the compression driver with directivity that increases with frequency. This provides flat axial response, but power response that typically falls by 6 dB per octave from as low as 3 kHz. The resulting decrease in coverage angle (as the frequency increases) gives generally poor control of the reverberant field and (in two-way designs) is not well matched to the coverage angle of the low frequency driver at the crossover frequency. By contrast, the JBL Bi-Radial ™ horn provides constant coverage over its operating bandwidth. Both on-axis and off-axis pressure response are flat, and the vertical coverage angle is identical to the horizontal. This angle is wide, 100° x 100°, but very tightly controlled, and it matches the coverage angle of the low frequency driver at the crossover frequency. Additionally, the horn's rapid flare rate reduces second harmonic distortion, and its reduced depth puts its driver in the same acoustic plane as the low frequency driver. The Bi-Radial ™ monitors present a coherent sound source, with extremely stable stereo imaging over a wide variety of listening positions. The monitors offer a high degree of placement flexibility, and the listening position can be quite close with no loss of stereo imaging.

Equalization of the 4430  will typically be needed only to correct for inherent room anomalies rather than for monitor response. This is the result of uniform frequency response within the coverage angle. The controlled power and polar response of the JBL Bi-Radial ™ monitors effectively removes them from the variables with which a recording engineer must contend.

 

HIGH FREQUENCY COMPRESSION DRIVER

The Bi-Radial ™ horn is coupled to a compression driver which is crossed over at I 000 Hz. The driver features a titanium diaphragm with a three-dimensional diamond-pattern suspension . Developed by JBL, this diamond surround offers an extended frequency response normally associated with exotic materials while retaining ruggedness and high power capacity. The diaphragm is pneumatically drawn to shape to eliminate stresses that cause fatigue, and a phasing plug of concentric exponential horns eliminates phase cancellation.

 

LOW FREQUENCY

The low frequency loudspeakers used in the Bi-Radial ™l monitors incorporate the latest technology to deliver smooth response, extended bandwidth, and extremely low distortion. The magnetic structures feature JBL's Symmetrical Field Geometry (SFGI design to reduce second harmonic distortion to inconsequential levels. New adhesives technology and coil former construction improve power handling. The coil itself, 100 mm (4 in) in diameter, is fabricated from edge-wound copper ribbon, and operates in a magnetic field having a flux density of 1.2 T (12,000 gauss). The 19 mm(% in) length of the voice coil allows increased linear excursion, and a careful choice of suspension elements helps to completely eliminate dynamic instabilities.

The 4430 differ chiefly in their low frequency capabilities. The 4430 uses a single 380 mm ( 15 in) low frequency driver and is 3 dB down at 32 Hz; it can handle full power input to 27 Hz.  The system is down 3 dB at 27 Hz and will handle full power down to 22 Hz. The systems use similar low frequency drivers, but the cone assemblies.

 

FREQUENCY DIVIDING NETWORK

The frequency dividing network of the Bi-Radial ™ monitors has a crossover frequency of I kHz and a nominal slope of 12 dB per octave. The cut-off slope and shape were chosen to provide the smoothest possible response over the widest bandwidth, restricting any off-axis anomalies to a very narrow portion. JBL has paid considerable attention to both the off-axis response and the total power response, and the network optimizes these parameters. While

the response is smooth at all angles, the flattest response is, by design, on-axis and above. This offers a greater number of listening positions when the system is mounted at or below ear level; for mounting above ear level, the system can be inverted to offer the same advantages. The network also provides equalization of the compression driver. Because the power response of the driver and the Bi-Radial ™ horn is greater in the midrange than at high frequencies, this equalization attenuates the lower end of the compression driver's response, lowering distortion and giving greater dynamic headroom. The equalization is provided in two stages, allowing separate adjustments (via front panel level controls) for the midrange and high frequencies.

A switch located adjacent to the connection terminals allows the monitor to be bi-amplified. A special crossover card is available for the IBL Model 5234A electronic frequency dividing network to provide the appropriate crossover characteristics.

 

Specifications

Frequency Response:  35 Hz - 16,000 kHz ±3 dB

Sensitivity:  93 dB SPL

Efficiency:  1,3%

Dispersion Angle

Horizontal :  100° (+10°; -30°)

Vertical :  100° (+0°, -30°)

Impedance:  8 Ω  nominal

Max. Power Input:  300 W

Continuous Sound Pressure Level:  119 dB

Crossover Frequency:  1,000 Hz

Driver Complement:

Low Frequency :  2235H

Compression Driver :  2425H

Horn :  2344

Enclosure Volume:  0,14m³ (5 cu. Ft)

Resonance Frequency:  34 Hz

Dimensions:  908 x 556 x 400 mm (480 mm deep w/horn)

Weight Net:  26 kg (57 lbs)

 

JBL4425 monitor loudspeakers

Bi-Radial Studio Monitor

The success of the models 4430 and 4435 Bi-radial studio monitor loudspeakers has prompted JBL to introduce a smaller model based on the same principles for use in smaller studios and for a variety of demanding audio production applications.

As in the case of the larger Bi-Radial monitors, the 4425 maintains a 100-degree-by-100-degree coverage pattern from its crossover frequency (1200 Hz) up to 16 kHz. Smooth power response is ensured from the lowest frequencies up to 1200 Hz, and flat power response is maintained above that frequency. At the same time, axial response is remarkably smooth, and the combination of controlled power and axial response ensures that the reflected sound field in the control room will be free of coloration. The model 4425 also addresses the requirement for accurate stereophonic imaging. The mirror imaged pair creates absolutely symmetrical sound fields, and this is the essential requirement for precise imaging. There is no lobbing for normal off-axis listening positions in the horizontal plane, and vertical lobbing is minimized over the preferred listening arc.

The model 4425 can handle program power inputs of 200 watts, more than enough to accommodate the high acoustical levels demanded in critical listening to today's digital recordings.

 

High-Frequency Horn and Driver

The BI-Radial horn used in the model 4425 is a scaled down version of the model 2344 horn used in the 4430 and 4435 monitor loudspeakers. It is made of high-impact structural foam and is acoustically inert. The high-frequency compression driver is a completely new design making use of a computer-machined phasing plug. Tolerances are held to a high degree, and unit-to-unit variation is small. The disphragm assembly is JBL's unique titanium design, with its advantages of extended frequency response relative freedom from mechanical fatigue, and high acoustical output capability. A copper shorting ring plated on the pole piece controls high-frequency impedance and improves high-frequency response.

As is the case with the larger Bi-Radial monitors, the 4425 system maintains precisely aligned phase response over a forty-gegree wide arc in the horizontal plane. The preferred listening arc in the vertical plane is between zero (on-axis) and ten degrees up.

 

Low-Frequency Transducer

A newly designed driver, the model 2214H, is used in the 4425 monitor loudspeaker. This transducer incorporates JBL's symmetrical field geometry (SFG) magnet structure for low distortion. The 76 mm (3-in) voice coil is made of edge-wound copper ribbon wire for highest sensitivity and power handling. The inner suspension of this transducer has been designed to exhibit a progressive increase in restoring force with increasing displacement. This controls dynamic offset for low-frequency, large excursion signals, and results in reduced distortion at low frequencies. A composite coating on the cone optimizes both damping and stiffness, resulting in smoother response and lower distortion.

 

Frequency Dividing Network

In addition to the normal function of frequency division, the network in the 4425 provides power response compensation for the high-frequency drier. Two controls allow the user to contour both mid and high frequencies to match various room characteristics. While the network slopes are 12 dB/octave, the combination of inherent roll-off characteristics in both high- and low-frequency components of the system with the electrical characteristics yields quite rapid transitions in the crossover frequency. Network components are of the most rugged, low-loss type, and high-quality bypass capacitors are placed in parallel with the larger capacitors in the signal path for increased linearity.

 

Specifications

Frequency Response:  40 Hz - 16,000 kHz ±3 dB

Sensitivity:  91 dB SPL

Efficiency:  0,8%

Dispersion Angle

Horizontal :  100° (+10°; -30°)

Vertical :  100° (+0°, -30°)

Impedance:  8 Ω  nominal

Max. Power Input:  200 W

Continuous Sound Pressure Level:  114 dB

Crossover Frequency:  1,200 Hz

Driver Complement:

Low Frequency :  2214H

Compression Driver :  2416H

Horn :  2342

Enclosure Volume:  53,8 l (1,9 cu. Ft.)

Resonance Frequency:  34 Hz

Dimensions:  406 x 635 x 311 mm (375 mm deep w/horn)

Weight Net:  26 kg (57 lbs)

 

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 Ω  nominal; 5 Ω  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 Ω  nominal; 5,6 Ω  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)