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

Cambridge 540A v2

Cambridge 540A v2 - High performance integrated amplifier
 For these version 2 models we have been able to further improve the audio quality and make them more powerful through many detailed changes and enhancements developed as a result of our on-going research programme. We have also added some new features, including support for Multi-Room use. All this proprietary engineering is housed within our low resonance, acoustically damped chassis. An Azur Navigator remote control is also provided, giving full remote control of four amplifier in an attractive and easy to use handset.
The 540A V2.0 features a new preamp stage with buffered inputs for lower crosstalk and improved stereo imaging, whilst the headphone output is now provided be a separate Class A headphone driver circuit. The amplifier stage has been revised with new low-noise input transistors, special driver stage PSU regulation, a new voltage amplifier topology and separate current sources for the voltage amplifier and predriver stages. These enhancements to the original circuits all work to elevate the sound quality to a new level. A new heatsink and transformer are employed and the power output is now 60 watts per channel (from 50 wpc on the V1 model).

With output at 60 watts per channel, the 540A Version 2 is a clear leader in budget amplifier circles offering a huge number of features and a build quality to embarrass more expensive rivals.
The 540A features full remote control and dedicated multi-room connections.
Other features:
60 watts Power output at 8 Ω
Amplifier type Class AB
Incognito Ready multi-room outputs
Tape and 5 analogue inputs
Headphone socket
Special CAp5 protection circit
Premium 3-way binding posts
Azur navigator remote control
All metal construction with Black or Silver Finishes

Power Output:
60 watts (into 8Ω)
90 watts (into 4Ω)
THD (unweighted)
Less than 0.002% at 1 kHz, of rated power
Less than 0.070% from 20Hz - 20 kHz, of rated power
Less than 0.025% from 20Hz - 20 kHz at 10 W
Frequency Response:  5 Hz - 50 kHz (-1 dB)
Signal-to-Noise Ratio (ref 1w):  better than 85 dB
Input Impedances:  47 k Ω
Power Amp Damping Factor:   better than 100 W
Max Power Consumption:  650 W
Min/On Power Consumption:  less than 35 W (no signal)
Standby Power Consumption:  less than 10 W
Bass/Treble Controls:  Shelving, ultimate boost/cut  ±7.5 dB (at 20 Hz and 20 kHz)
Dimensions (W x H x D): 430 x 100 x 310 mm (16,9 x 3.9 x 12.2”)
Weight:  7.4 kg (16.3 lbs)

Cambridge 540C v2

As with previous Azur CD players, the 540C V2.0 make use of a custom Cambridge Audio servo solution and transport, at the heart of which is a VLSI (Very Large Scale Integration) circuit which dynamically adjusts in real time the focusing, tracking and output level of the laser for the maximum retrieval of digital information. To ensure the very best performance there are also multiple separate power supplies for the D/A converter circuitry, audio filters, clocks and other stages, as well as extensive use of low impedance film capacitors.
For the Version 2 models, we have significantly upgraded and improved the Digital to Analog stages as well as the anti-aliasing filters for even better sound quality and have added features that allow these products to be used in Custom Install applications. All this proprietary engineering is housed within our low resonance, acoustically damped chassis. An Azur Navigator remote control is also provided, giving full remote control of your CD player in an attractive and easy to use handset.
About the 540C V2.0
The 540C V2.0 now employs a WM8740 24 bit/192 kHz capable Digital to Analog converter from Wolfson Microelectronics. This very high quality part is coupled to a new three pole Double Virtual Earth Balanced filter design for very low noise and distortion. A new toroidal transformer is now fitted giving lower noise and less waveform distortion, for quieter PSU operation. Finally, to allow seamless integration with multi-room entertainment systems, a Control Bus input and output have been fitted, as has an IR emitter input.

Cambridge 540C v2 - five star CD player
The Azur 540 C boasts performance, build quality and a specification to embarrass not just its immediate rivals, but many CD players costing at least twice the price.
New features include an upgraded DAC abd Control Bus connections for easier multi-roomcontrol
Electronics sit on a low resonance, acoustically damped chassis and like all Azur products, the 540C is housed within a solid aluminium fronted case.
 Other Features:
Single Wolfson WM8740 DAC
CD-R/RW playback
Control Bus and IR emmiter in
Dimmable display
Azur navigator remote control
All metal construction and blac/silver finishes

D/A Converter:  Wolfson WM8740 24-Bit/192 kHz capable
Filter:  3 Pole Double Virtual Earth balanced
Frequency Response:  (±0.2 dB) 20 Hz to 20 kHz
Total Harmonic Distortion :
at 1 kHz (0 dBFs):  less than 0.0015%
at1 kHz  (-10 dBFs):  less than 0.0010%
at 20 kHz (0 dBFs):  less than 0.0080%
Intermodulation Distortionn (19/20 kHz) 0 dBFs:  less than 0.0015%
Linearity at -90 dBFs:   ±0.5 dB
Clock Deviation:  ± 10 p_pm
Stopband Rejection (>24kHz):  less than 90 dB
Signal-to-Noise  Ratio (A weighted):  less than  100 dB
Total Correlated Jitter:  better than 210 pS
Crosstalk at 1 kHz:  better than -100 dB
Crosstalk at 20 kHz:  better than -90 dB
Output Impedance:  better than 50 Ω
Dimensions ( H x W x D):  70 x 430 x 310 mm
Weight:  4.6 kg (10.1 lbs)

Cambridge 540P

Cambridge 540P - MM phono pre-amplifier
The entry-level 540P is a high quality Moving Magnet design featuring single-ended "Class A" gain stages and a discrete transistor input stage instead of the more common integrated circuits. The 540P employs a highly accurate active RIAA equalisation system. The rear panel benefits from gold plated input connectors to minimise signal path interference and reduce surface degradation. An external 12 volt power supply comes as standard.
This unit feature the now customary Azur steel chassis and a robust anodised aluminium front plate.
Max Power Consumption:  5 W
Gain at 1 kHz :  39 dB
Nominal Output :  300 mV
Sensitivity for Nominal Output:  3,35 mV
Total Harmonic Distortion:  less than 0,009% (20 - 20,000 Hz)
RIAA Curve Accuracy:  less than ±0,65 dB (25 -20,000 Hz)
Signal-to-Noise Ratio:  better than 85 dB (using Audio Precision RIAA-1 with grounded inputs)
Crosstalk at 20 kHz :  better than 76 dB
Dimensions (H x W x D):  46 x 215 x 133 mm (1,8" x 8,5" x 5,2")
Weight:  0,8 kg (1,8 lbs)

Pioneer CT-F850

Stereo Cassette Deck with 3-Head/2-Motor DC Drive, Closed-Loop Dual Capstan and 2-Mode Electronic Fluroscan Meter
3-head Monitor-Capable with "Small-Window" erase Head
Pioneer Sendust Metal-Capable Heads & Wide-Range Electronics
2-Motor DC and Closed-Loop Dual Capstan Drive, Wow/Flutter 0,04%
19-Segment Electronic 2-Mode Fluroscan meter
Continuously -Adjustable Bias, logic Controls, Dolby NR and more.

The Metal-Capable Deck
The search for the ideal material to assure a clean, bright and undistorted "reflection" on playback  has finally come to an end with the so-called "metal" casettes.  But Pioneer would like to remind you that all our new metal-capable cassette decks, including the CT-F850, have been wholly redesigned to handle metal and all other types of tapes with greatly enhanced performance. Therefore, we recommend that you consider such features as the 3-Head Monitor-Capable configuration and the 2-Motor DC Closed-Loop Dual Capstan drive system in this deck as having at least as much (maybe more) importanmce as its metal-tape-handling capabilities. These and other features combine to make this, our "third best" deck, a wise investment in non-obsolescence, one that will always reflect the finest in high fidelity recording and playback.

All Cassettes are "Metal" in a sense.
If you want to split hairs, all cassette tapes could be called "metal" because all use one form or another of tiny ferriferous metal particles to receive and hold the magnetically-encoded sound information passed on from the recording head. Unitl recently, those metal particles were oxided ("rusted") for easier handling. This naturally reduced their ability to accept high inputs, especially in the high frequencies. In other words, they had relatively low Hc (coercivity) and Br (remanent flux) characteristics.
But the New "Metal" Tapes are Extraordinary.
The Hc of "Normal" tapes was between 280 and 330 Oersted. Br was in the range of 1,200 Gauss. Improvements were made with the use of chromium dioxides (CrO₂) and so on, boosting the Hc to as high as 550 oersted and the Br to 1,600 Gauss. But with non-oxided metal emulsion, the new metal tapes offer Hc of 950 - 1,100 Oersted and Br as high as 3,500 Gauss. However, to take full advantage of these astonishing improvements, metal-capable decks must have very special heads and electronics. All Pioneer decks, the CT-F850 ranking in the middle of the line in terms of price and features, have those much needed improvements.

Two-Motor DC Drive
Perfect Tape-to-Head Contact
Pioneer has improved the once-popular Closed-Loop Dual Capstan system to avoid slack, snaris and stretching in the tape while keeping it in perfct contact with the heads. The key is our Automatic Tape-Slack Canceller which puts the proper tension on the tape before the pinch rollers are engaged. Then,the "drive" capstan on the right and the "tension" capstan on the left are looped via the sub-belt (with appropriate compensation) so that they rotate at exactly the same speed. Your recorded/played signals retain the same pitch and level from one end of your tape to the other.
Both Motors are DC
With the use of DC motors in the CT-F850 we have avoided speed. Fluctuations caused by voltage/frequency variations in the power supply. The DC motor for the reels  is a high-torque type exhibiting excellent high-speed performance over very long periods of time, it is physically "de-coupled" from the capstan drive system to further reduce vibration. Then, the DC motor for capstan drive is a servo type coupled with the large flywheel by a flat precision-finished belt. Tape speeds are rock-steady at all times because the speed of the motor is electronically controlled instant by instant. The proof is in the excellent wow/flutter of 0,04% (WRMS)

3-Head Heat-Sink Mounting
Mutual interference is kept to a minimum by housing the REC and Play heads in separate housing. But this Pioneer developed 3-head deck system uses a single die-cast aluminum mount, including the "small-window" erase.the thick and rigid structure dissipates heat effectively to prevent head malfunction.
Another 3-head Advantage
Tape/Source monitoring is surely a major advantage in 3-head decks. But did you know that using gaps of different width on our seoarate Rec and Play heads also improves performance. This is another strong reason to spend that little extra to make your deck a 3-head model from Pioneer.

Systems:  Compact cassette, 2-hannel stereo
Motors:  Capstan drive, DC servo Motor x 1
Reel drive:  DC high torque motor x 1
Heads:  Sendust Recording/Playback combination type head x 1
Erasing head x 1
Fast Winding Time:  approx. 85 sec. (C-60 tape)
Wow and Flutter:  no more than 0,04% (WRMS)
No more than ±0,14% (DIN)
Frequency Response (-20 dB Recording): 
Standard, LH tapes:  20 to 17,00 Hz ; (25 to 15,000 Hz ±3 dB)
Ferrichrome tape:  20 to 18,000 Hz ; (25 to 17,000 Hz ±3 dB)
Chromium dioxide tape :  20 to 18,000 Hz ; (25 to 17,000 Hz ±3 dB)
Metal tape :  20 to 19,000 Hz ; (25 to 18,000 Hz ±3 dB)
Frequency Response (0 dB  Recording):
Chromium dioxide tape :  20 to 11,000 Hz
Metal tape:  20 to 14,000 Hz
Signal-to-Noise Ratio:
Dolby NR Off :  more than 59 dB
Dolby NR On :  more than 69 dB (over 5 kHz)
Total Harmonic Distortion:  no more than 1,2% (0 dB)
Inputs Sensitivity/Max.Input/Impedance:
Mic :  0,3 mV/100 mV / 10 k Ω (6 mm Jack, ref. Mic Impedance 250 Ω to 10 k Ω)
Line x 2 :  64 mV/ 25 V / 85 k Ω (Pin Jack)
Outputs Ref. Level/ Max. Level / Load Impedance
Line x 2 :  450 mV/630 mV / 50 k Ω (Pin Jack)
Hedaphones :  70 mV/ 98 mV / 8 Ω (6 mm Jack)
Amplifier Section:  49 Transistors; 10 Ics; 41 Diodes; 3 Zener Diodes; 7 LEDs
Motor Control Section:  3 Transistors; 1 Diode
Dolby NR system (ON-OFF)  with LED indicator lamp
Fluorescence tube level meter (-20 to +8 dB)(peak/Average Selector)
Biasfine adjusting control knob
4 position tape selector (STD/METAL/CrO₂/Fe-Cr)
Automatic Tape slack canceller
Cassette compartment illumination
Standby mechanism with unattended recording
Output level controls with click stop for reference playback level
Power Requirements:  AC 120, 220, 240 V (switchable)50/60 Hz
Power Consumption:  45 watts or 50 watts
Dimensions (W x H x D): 420 x 150 x 361  mm (16-9/16" x 5-15/16" x 14-1/4")
[452 x 160 x 361 mm (17-13/16" x 5-5/16" x 14-1/4") D/G model]
Weight:  9,5 kg (20 lb 14 oz) [9,9 kg (21 lb 12 oz D/G model]

Pioneer CT-F 7272

Front-Access Stereo Cassette Deck with Pioneer-Exclusive Automatic Chrome Detection, Vertical Cassette Hold, Dolby, Memory Stop and Other Advanced Features.
The Pioneer CT-F7272 isn't the most elaborate nor expensive deck on the market. But it has a number of exclusive features that add up to the kind of handling convenience and musical quality that aren't normally found in its price range. Among them is the Pioneer-perfected Automatic Chrome Detection System to eliminate the guesswork when you use wide-range Chrome tapes. It switches the Bias/Equalization to the correct values for Chrome, and also makes it easy to take advantage of the newer Ferrichrome as well as standard low-noise tapes. Advanced features like the Pioneer-exclusive Vertical-Hold Cassette Compartment help you realize the full potential of the space-saving front-loading format.

Tapes are held firmly upright so you can read labels and see tape movement. All controls are up front for quick access. They include those for Dolby, Memory Stop and the easy-touch pause and tape-transport keys. Big, accurate Vus twin Chrome/ferrichrome indicator s, LEDs for Rec and Dolby modes and separate controls for input and output improve handling ease.  Inside there's a wide-dynamic -range preamp plus a precision DC tape drive system with low wow/flutter, a tough Ferrite-Solid head, a built-in MPX noise filter for recording FM stereo , and more. The Pioneer CT-F7272  is guaranteed by Pioneer to bring you the convenience and quality you can't beat in its price range.

System:  Compact cassette, 2-channel stereo
Motor:  Electronically-controlled DC motor (built-in generator x 1)
1 x Ferrite Solid recording/playback head
1 x Ferrite erasing head
Fast Winding Time:  appox. 85 sec. (C-60 tape)
Wow and Flutter: 
no mor than 0,07% WRMS (JIS),
no more than ±0,19% WRMS (DIN)
Frequency Response:
Standard LH Tape :  30 to 14,000 Hz (40 - 13,000 Hz ±3 dB)
Chromium Dioxide Tape :  30 to 17,000 Hz ((40 - 15,000 Hz ±3 dB)
Ferri-chrome Tape :  30 to 16,000 Hz (40 - 15,000 Hz ±3 dB)
Signal-to-Noise Ratio:
Dolby OFF : more than 52 dB
Dolby ON :  more than 62 dB
(over 5 kHz, standard, LH tape)
When chromium dioxide tape is used,, Signal-to-Noise ratio is further improved by 4,5 dB over 5 kHz : more than 57 dB (DIN)
Total Harmonic Distortion:  no more than 1,7 %
Input Sensitivity/Impedance:
MIC x 2 :  0,23 mV/80 mV / 23 k Ω, (ref.MIC impedance; 600 Ω to 50 k Ω)
Line x 2 :  64 mV/25V / 100 k Ω
DIN Rec/Play  (Input/Output):  10 mV/3,6 V / 2,2 k Ω (5 pin DIN standard)
Output level/Impedance:
Line x 2 :  450 mV/ 800 mV/ 50 k Ω
Headphone :  60 mV/ 100 mV / 8 Ω
DIN Rec/Play :   450 mV/ 800 mV/ 50 k Ω
Amplifier Section:  35 Transistors; 22 Diodes; 1 Zener Diode; 2 FETs; 2 LEDs; 2 Dolby Module
Motor Control Section:  3 Transistors; 1 Diode
Dolby system (on/off) with indicator lamp
Tape selector (STD/FeCr/CrO₂) with CrO₂, Fe-Cr indicator lamp and chrome tape Auto-switchable mechanism
Cassette compartment illumination
Memory stop mechanism (on/off)
Power requirement:  AC 120 V, 50/60 Hz
Power Consumption:  18 watts
Dimensions (W x H x D):  453 x 177 x 343 mm (17-13/16" x 6-15/16' x 13-1/2")
Weight (without package): 9,5 kg ( 20 lb 15 oz)

McIntosh MC 3500

The McIntosh MC 3500 sets a new precedent in high power performance and flexibility.
Many years of diligent research, space age product advances and careful examinations  of new developments in component parts have lead to the McIntosh MC 3500, a new Laboratory Standard.
The quality performance that is demanded in the scientific laboratory  is your for the highest performance in a home music system.

McIntosh  developed the first low distortion, high quality, high powered amplifier in 1947. the secret then was the Unity Coupled circuit and Bifilar Output Transformer.
The MC 3500 has made another new advance. Again transformer design has made the difference. A new output transformer with 5 primary windings, interleaved with the secondary to give you maximum output, lowest distortion, multiple output impedance for any type type of sound distribution requirement. The new McIntosh Pentafilar output transformer and Unity Coupled circuit means lowest distortion, flat power response, long, trouble free cooler operation at high power.

McIntosh has produced the answer to the majority of sound problems. With the McIntosh MC 3500, your music system will produce music as never before. All the instruments will be reproduced with clarity and accuracy. No more will you hear just a barrage of sound. Now you will hear each instrument clearly and cleanly without the cloudiness produced by the lack of power in the amplifier. The McIntosh MC 3500 is the ultimate in high power amplifiers.

Power Output:  350 RMS watts continuous
Harmonic Distortion:  0,15% at 350 watts power output from 20 Hz to 20 kHz. Typical performance is less than 0,1% at rated power. Distortion decreases as output power is reduced.
Frequency Response:  20 Hz - 20,000 Hz (+0 -0,1 dB at rated output); 7 Hz - 70,000 Hz (+0 -3,0 dB at 1 watt)
Noise and Hum:  95 dB below rated output
Output Impedance and Voltage:  1 Ω/ 17,3 V; 4 Ω/35,8 V; 8 Ω/53 V; 16 Ω/75 V; 50 Ω/132V; 64 Ω/150 V. may be operated isolated from ground. (1 Ω/17,3 V output is rated to 300 watts, and 4 Ω/35,8 V output is rated to 320 watts)
The 75 Volt output is used to power 70,7 V sound distribution lines. The 150 V output is used to power 141,4 V distribution Lines. The 132 Volt output is used to provide 117 V for laboratory or industrial applications.
Internal Impedance:  about 5% of rated load Impedance. The 1 Ω/17,3 V output is rated about . 1 Ω
Input Impedance:  200,000 Ω
Input Sensitivity:  1,1 volts. Level control provided for higher input voltages.
Power Requirement:  117 volts AC 50/60 Hz, 400 watts at zero signal output:  900 watts at rated output.
Solid State Complement:  3 Silicon Transistors; 2 Silicon Zener Diodes; 3 Germanium Diodes; 9 Silicon Retifiers and Diodes
Tube Complement:  2 x 12AX7; 2 x 6DJ8; 1 x 6CG7; 1 x 6BL7; 8 x 6LO6
Front panel :  10-1/2" (high), 19" (wide)
Chassis :  17" behind panel including connections
Knobs project 2" in front of panel.
Front panel :  Gold anodized aluminum and black
Chassis :  Chrome and black
Weight (Chassis only):  125 pounds (shipping 135 pounds)

Mark Levinson ML-2

ML-2 Monophonic Power Amplifier
ML-2 Class A power Amplifier in the appropriate system will produce striking sonic results. Each musical instrument is more articulated, while clear and open sound is maintained. Harshness seems to disappear from instruments with higher frequency content, such as violins. Music takes on more body and fullness. Absolute solidity of deep bass gives the entire performance an essential foundation and enables the listener to hear notes and passages that were previously inaudible. With quality recordings, the image of a performance is precise and remarkably stable appearing to emanate from a wider, taller and deeper stage.

The ML-2 may be operated in either the inverting or non-inverting mode. This allows a pair to be used in bridged configuration without additional circuitry. In bridged mode, two Ml-2s deliver twice the output voltage and four times the power. The power supply is fully regulated under all operating conditions. The ML-2 offers completely modular construction allowing efficient up-dating 9when available) and ease of servicing if required.
While outstanding performance can be achieved in high power amplifier designgs, the refined sound quality offered by ML-2s can only be attained by a design that, by today's standards, is limited in output voltage. The ML-2 is rated at 25 watts continuous sine wave power into 8 ohms from 20 Hz to 20 kHz with no more than 1% THD. For this reason, Ml-2s work best with higher efficiency loudspeakers, in multi-amp systems, or with lower efficiency speakers where loud listening levels are not required. While Ml-2s may not be optimum for every application, in the appropriate system they offer a beauty of musical sound unachievable by any other design.

Specifications ML-2:
Rated Power:  25 watts minimum continuous sine-wave power into 8 Ω from 20 Hz - 20 kHz with no more than 1% THD.  
Input Impedance:  100,000 Ω
Power Supply:  AC 100, 120, 220, 240 Volts, 50/60 Hz
Power Requirement:  400 Watts nominal, 50 - 400 Hz
Connector Complement:  2 Camac coaxial connectors; 13-pin audio connector (XLR); 5 binding posts; 1 AC receptacle/line voltage selector
Dimensions (overall W x H x D):  483 x 216 x 546 mm (19" x 8,5" x 21,5")
Weight:  29,6 kg ( 65 pounds)

B&W DM 4

The DM4 was released at the International Audio Fair, October 1972 in the firm belief that the design aims have been achieved, and from extensive comparasion with other systems currently available we believe the DM4 may well out-perform competitive loudspeaker systems of three times the size and twice the price.
The DM4 is a 3-unit loudspeaker comprising highly developed Bextrene coned Bass/Mid-range unit (designed and produced in our own factory), type HF1300 Mk II lower high frequency unit and a 19 mm plastic domed upper high frequency unit. Third oreder Butterworth filters are used throughout and the crossover unit closely integrates the optimum performance of the three units to give an exceptionally smooth response extending from 30 Hz to above 25 kHz.
The DM4 monitor is individually pen tested in anechoic chamber and supplied with automatic pen plot showing frequency response.

Stand-mount/Bookshelf loudspeaker system
Product Summary
The DM4 is a three-unit monitor loudspeaker system that produces high quality results from an incredibly small cabinet, making it perfect for home or small studio where space is at a premium. Acoustic loading is by a very dense, critically damped enclosure with a small controlling vent to optimise the response between 60 and 120 Hz. This also produces considerably reduction in cone excursion from 30 to 60 Hz.

Technical highlights
The bass/midrange units come in a critically contoured Bextrene cone configuration. This is laminated in a highly resistant damping compound that ensures linear frequency response to at least an octave above crossover.
The upper mid frequency unit offers wide dispersion from a virtual point source and a 19mm low diaphragm mass plastic dome unit extends frequency response to above 25 kHz
Constructed of 19 mm 750 density chipboard throughout with inside balancing  veneers. All battens pinned and glued , Choice of teak, Walnut or Rosewood veneers plus a satin white finish.

Drive Units:
High Frequency :  1 x 19 mm voice coil
Mid Frequency :  1 x 34 mm mid/high frequency unit
Low Frequency :  1 x 164 mm bass/midrange unit
Frequency Response30 Hz 25 kHz. Better than ± 2dB,
Sensitivity4,8 watts into nominal impedance (i.e 6.2 volts) for a sound pressure of 95 dB pink noise at 1 metre
Nominal Impedance8 Ω
Power Handling:  10 W – 30 W
Dimensions (H x W x D):  531 x 255 x 255 mm (21" x 10" x 10")
Weight:  11,1 kg (24 lb 6 oz)
Standard:  teak or walnut
Special:  satin white or selected veneersof rosewood or black ash

I like 

Onkyo TA-630D

 Stereo Cassette Tape Deck
A full-feature front loading cassette deck with phase-locked loop (PLL) servo DC motor drive system and unique "Accu-Bias" control for complete tape compatibility. Equipped with a newly developed hyperbolic S&S sendust rec/pb head, Dolby NR with MPX filter, memory rewind full auto stop mechanism, timer start/pause function, rec-mute switch and large VU meter with two peak level indicators.

Accu-Bias is Onkyo's exclusive system. It works with a pair of reference signal generators built into the TA-630D. Feed these signals to your tape, and read the reproduction signal on the meters. If bias is off for that cassette tape, you compensate with continuous variable settings until you get an absolutely flat frequency response. It's that simple, and you get the best high frequency response, least distortion and lowest signal to noise ratio.
 High Quality Long Life "S&S" Sandust Head
Onkyo's recently developed "S&S" Sedust head (made from a highy robust silicon/iron/aluminum alloy of outstanding magnetic properties) plays a very big role in achieving the high quality of sound reproduction in the TA-630D. Extended frequency response 920 Hz - 18,000 Hz with chrome tapes) and an exceptionally wide dynamic range make your recordings sound professional-like.

Other important features:
Dolby NR System with Switchable MPX Filter
Built-in Dolby FM Decoder
Timer Switch for Automatic recording or monitoring Alarm
One-Touch Rec Muting for Clean Editing
Memory rewind for Rapid replay
Separate 3-Way Bias and Equalization Selectors
Full Auto-Stop mechanism
Track Format:  4-track, 2-channel
Erase System: AC erase
Tape Speed:  4,8 cm/sec
Wow and Flutter:  0,048% (WRMS)
Fast Forward and Rewind Time:  90 sec (C-60)
Frequency Response:
Normal Tape :  30 -15,000 Hz
CrO₂ Tape :  30 -18,000 Hz
FeCr Tape :  30 - 18,000 Hz
Signal-to-Noise Ratio:  68 dB (FeCr tape, Dolby NR in, Dolby level)
Transistors:  40
SCR:  1
IC:  4
Diodes:  25 diodes, 3 LED
Input Terminals:
Microphone jacks : 2
Minimum Input level :  0,3 mV
Input Impedance : 50 k Ω
Optimum Mic Impedance:  200 Ω - 50 k Ω
Line in Jacks : 2
Minimum Input level :   50 mV
Input Impedance :  50  k Ω
DIN Jacks : 1
Minimum Input Level :  0,1 mV/k Ω
Input Impedance :  5 k Ω
Output Jacks
Line Out jacks :  2
Standard Output level :  0,775 V (0 VU)
Optimum Load Impedance:  over 50 k Ω
DIN Jack: 1
Standard Output Level :  0,775 V (0 VU)
Optimum Load Impedance :  over 50 k Ω
Headphones :  8 Ω - 200 Ω
Motor:  PLL Servo DC
Power Supply:  AC 120 V, 60 Hz (for USA and Canada)
AC 110/120/220/240 V, 50/60 Hz or 240 V, 50 Hz  ( for other countries)
Power Consumption:  13 W
Dimensions (W x H x D):  418 x 158 x 297 mm (16-1/2" x 6-1/4" x 12"
Weight:  6 kg (13,2 lbs)

Onkyo TA-2010

Stereo cassette tape Deck
The most affordable way to enjoy high fidelity cassette recording and playback with all-tape compatibility. Featuring Onkyo's own :Accu-Bias" adjust control, long-life superb permalloy Widex rec/pb head, Dolby NR with MPX filter, Dolby referenced VU meters, separate 3-position bias/EQ tape selectors, end-of-tape shut off and pause/edit control.

Track System:  4-track, 2-channel stereo
Recording System:  AC bias
Erasing System:  AC erase
Tape Speed:  4,8 cm/sec
Wow and Flutter:  0,08% (WRMS)
Frequency Response:
Normal Tape :  20 - 14,000 Hz
FeCr Tape :  20 - 16,000 Hz
High Tape :  20 - 16,000 Hz
Signal-to-Noise Ratio:   54 dB (Dolby NR Out, FeCr tape)
A nooise reduction of 10 dB above 5 kHz and 5 dB at 1 kHz is possible with the Dolby NR in.
Input Jacks:
Microphone Jacks :  2
Minimum Input Level/Impedance:  0,3 mV/5 k Ω
Optimum Mic Impedance :  200 Ω - 50 k Ω
Line In Jacks : 22
Minimum Input Level/Impedance :  50 mV/50 k Ω
Line : 2
Output Level :  0,480 V ( at 0 VU)
Impedance :  over 50 k Ω
Headphone :  1
Impedance :  8 Ω / 200 Ω
Motor :  DC servo-motor
Heads:  Hard Permalloy Heads
Mechanism Specifications
Tape Speed: 4,8 cm/sec (3 kHz =3%, -2%)
Wow and Flutter:  less than 0,08% (WRMS)
Take-up Torque:  35 - 70 gr-cm
F.F. Torque:  55-130 gr-cm
Rwind Torque:  55-130 gr-cm
Automatic Shut-Off Time:  less than 5 sec
Components:  15 Transistors; 11 Diodes;  2 IC; 3 LED
Power Supply:  AC 120 V 60 Hz ( U.S.A. model) or AC 110/120/220/240 V 50/60 Hz
Power Consumption:  8,5 W
Dimensions (W x H x D):  418 x 150 x 250 mm (16-7/16" x 5-5/16" x 9-13/16")
Weight:  4,8 kg  (10,6 lbs)

Kenwood KR-950B

Kenwood KR-950
Quartz Synthesizer Hi-Speed DC Receiver
Front panel MM/MC cartridge selection
Two-way tape dubbing LED power meters
Quartz PLL frequency synthesized tuner
Automatic seek tuning with High and Low sensitivity selector
6 FM and 6 AM memory presets

Audio Sections
Power Output:  80 W/ch min. RMS, both channels driven into 8 ohms, 20 Hz to 20 kHz with no more than 0,015% THD
Both Channels Driven ( into 8 Ω at 1 kHz):  85 W + 85 W
Dynamic Power Output (at 4 Ω):  250 W
Total Harmonic Distortion (20 Hz -20 kHz from Aux):
Rated power into 8 Ω :  0,015%
1 watt power into 8 Ω :  0,01%
Intermodulation Distortion (60 Hz :7 kHz = 4:1 SMPTE):
Rated power into 8 Ω :  0,01%
Damping Factor:  40 at 1 kHz, 8 Ω
Transist Response:
Rise Time :  2 µs
Slew Rate :  ±50 V/µs
Input Sensitivity/Impedance:
Phono MM :  2,5 mv/ 50 k Ω
Phono MC :  0,25 mv/100 Ω
Tuner,Aux,Tape Play :  150 mV/50 k Ω
Signal-to-Noise Ratio (A weighted):
Phono MM :  86 dB for 2,5 mV input
Phono MM :  92 dB for 5,0 mV input
Phono MC :  68 dB for 0,25 mV input
Tuner,Aux,Tape Play :  104 dB for 105 mV input
Phono Max. Input Level (at 1 kHz):
MM :  200 mV (RMS), THD0,01%
MC :  30 mV (RMS), THD0,1%
Frequency Response:
Phono RIAA Standard  Curve:  20 Hz to 20 kHz ±0,3 dB
Over All (Aux ->Spkr.):  DC Hz to 160 kHz +0 dB, -3 dB
Tone Control:
Bass :  ±8 dB at 100 Hz
Treble :  ±8 dB at 10 kHz
Low :  6 dB/oct at 18 Hz
High :  6 dB/oct at 5 kHz
Loudness Control (Vol -30 dB):  +10 dB at 100 Hz
Output Level/Impedance:
Tape Rec Out (PIN):  150 mV/ 1 k Ω
FM Tuner Section
Usable Sensitivity:  10,8 dBf (1,9 µV)
50 dB Quieting Sensitivity:
Mono :  14,2 dBf (2,8 µV)
Stereo :  36,8 dBf (38 µV)
Signal-to-Noise Ratio at 65 dBf:
Mono :  80 dB
Stereo :  74 dB
Total Harmonic Distortion at 1 kHz:
Mono :  0,07%
Stereo :  0,08%
Frequency Response:  30 Hz to 15 kHz +0,5 dB -2 dB
Image rejection Ratio:  80 dB
Spurious Response ratio:  95 dB
IF Response Ratio:  95 dB
Alternate Channel Selectivity:  60 dB at ±400 kHz
AM Suppression Ratio:  60 dB
Stereo Separation:  50 dB at 1 kHz; 40 dB at 50 Hz to 10 kHz
Antenna Impedance: 
Balanced :  300 Ω
Unbalanced :  75 Ω
FM Frequency Range:  87,5 MHz - 108 MHz
AM Tuner Section
Usable Sensitivity:  10 µV (400 µV/m)
Signal-to-Noise Ratio:  48 dB
Image Rejection Ratio:  40 dB
Selectivity:  25 dB
Power Consumption:  65 W (no signal); 3,5 A (UL and CSA); 450 W (IEC); 450 W (others)
AC Outlet:  Switched2, Unswitched 1
Dimensions (W x H x D):  480 x 142 x 350 mm (18-29/32" x 5-19/32" x 13-25/32")
Weight:  9,0 kg (19,8 lb) net