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

Yamaha R-9

Uncommon sounds. Sounds that make exceptional demands on your audio system. Because from the crescendo of a massed chorale to the detonation of proton torpedos, the sounds of modern entertainment reward audio high-performance as never before. And nothing performs like Yamaha.
Yamaha's sophisticated new R-9 receiver is designed to make the most of today's home entertainment possibilities. With seven audio and three video hookups, the R-9 can serve as the control panel for your entire home audio/video system. And because it has a separates-quality 125 watt per channel amplifier with Auto Class A Power amplification, it provides tha high power and wide dynamic range that add a whole new dimension to your home entertainment experience.

Now you can hear digital recordings and compact disc reproduced with the full clarity and resonance demanded by serious audiophiles. Experience the high-decibel impact of the sound effects that make your favorite films special. And do it through a receiver so advanced it uses discrete circuitry like that found in Yamaha's finest separate components.

The R-9's AM/FM stereo tuner features digital tuning with a unique 5-digit capability that allows you to fine-tune in increments of 0,01 MHz (FM).
This is particularly helpful in obtaining maxinum signal quality when tuning relatively weak stations interfered with by stronger adjacent stations.
Combined with our new Computer Servo Lock Tuning System, it gives you the best of both digital and analog tuning capabilities.
The Yamaha R-9 includes a multi-function infrared remote control. And it is just one in a complete line of advanced Yamaha receivers. Now that's entertainment.

Audio Section
Continuous Power Per Channel:
125 W (20 Hz - 20 kHz 0,15% THD; 8 Ω)
145 W (20 Hz - 20 kHz 0,03% THD; 6 Ω)
145 W (1 kHz 0,01% THD; 8 Ω)
Dynamic headroom: 1,58 dB (8 Ω)
Dynamic Power:
180 W at  8 Ω (1 kHz/channel)
220 W at  6 Ω (1 kHz/channel)
280 W at  4 Ω (1 kHz/channel)
360 W at 2 Ω (1 kHz/channel)
Power Bandwidth:  62,5 W, 8 Ω, 0,08% THD, 10 Hz - 50 kHz
Damping Factor:  60 (1 kHz, 8 Ω)
Input Sensitivity/Impedance
Phono MC :  160 µV/220 Ω
Phono MM :  2,5 mV/47 k Ω
CD, Tape, Video :  150 mV/47 k Ω
Receiver (Accessory):  150 mV/47 k Ω
Input Sensitivity (new IHF):
Phono MC :  14 µV
Phono MM :  0,22 mV
CD,Tape,Video :  13,4 mV
Maximum Input Signal (1 kHz)
Phono MC :  8 mV (0,01% THD)
Phono MM :  110 mV (0,1% THD)
Output level/Impedance:
Rec Out :  150 mV/470 Ω
Headphone Jack Rated Output/Impedance:  0,91 V/270 Ω (0,015% THD)
Frequency Response:  20 Hz - 20 kHz +0 -0,3 dB (CD,Tape Video)
RIAA Equalization Deviation
Phono MC RIAA :  ±0,5 dB (30 Hz - 20 kHz)
Phono MM RIAA :  ±0,3 dB (20 Hz - 20 kHz)
Total Harmonic Distortion (20 Hz - 20 kHz):
Phono MC to Rec Out (3 V) :  0,005%
Phono MM to Rec Out (3 V) :  0,003%
cD, Tape to SP Out (62,5 W/8 Ω) :  0,015%
Video to SP Out (62,5 W/8 Ω) :  0,02%
Intermodulation Distortion:
CD,Tape, Video  :  0,01% (Rated Output /8 Ω)
Signal-to-Noise Ratio
Phono MC :  75 dB (500 µV, Input Shorted)
Phono MM :  92 dB (5 mV, Input Sshorted)
CD, Tape :  103 dB (Input Shorted)
Video :  91 dB (Input Shorted)
Signal-to-Noise Ratio (new IHF):
Phono MC :  74,5 dB
Phono MM :  75 dB
CD, Tape :  80 dB
Residual Noise (IHF A-network):  120 µV
Channel Separation
Phono MM :  60 dB (1 kHz, Input Shorted, Vol. -20 dB)
CD, tape Video :  60 dB (1khz, 5,1 k Ω)
Tone Control Charecteristics
Bass  Control
Boost/Cut :  ±10 dB at 50 Hz
Turnover Frequency :  350 Hz
Treble Control
Boost/Cut :  ±10 dB at 20 kHz
Turnover Frequency :  3,5 kHz
 Control Range :  ±12 dB at 1 kHz
Center Frequency :  1 kHz
Flter Characteristics
Low (Subsonic, Builtin):  10 Hz, -12 dB/oct
Continuous Loudness Control (Level-related equalization)
Attenuation :  -40 dB at 1 kHz
Audio Muting :  -20 dB
FM Section
Tuning Range:  87,5 MHz - 108 MHz
50 dB Quieting Sesitivity (IHF)
Mono [75 Ω] :  1,5 µV (14,8 dBf)
Stereo [75 Ω]:  20 µV (37,3 dBf)
Usable Sensitivity (IHF Mono) :  30 dB S/NQuieting, 75 Ω:  0,75 µV (8,8 dBf)
Image Response Ratio:  40 dB
IF Response Ratio:  90 dB
Spurious Response Ratio:  70 dB
AM Suppression Ratio:  55 dB
Capture Ratio
Local :  1,2 dB
DX :  2,5 dB
Alternate Channel Selectivity
DX :  85 dB
Signal-to-Noise Ratio
Mono :  85 dB
Stereo :  81 dB
Total Harmonic Distortion [MONO]
100 Hz :  0,05%
1 kHz :  0,05%
6 kHz :  0,1%
Total Harmonic Distortion {STEREO}
100 Hz :  0,07%
1 kHz :  0,07%
6 kHz :  0,15%
Stereo Separation (Local)
50 Hz :  45 dB
1 kHz :  50 dB
10 kHz :  45 dB
Frequency Response;  30 Hz - 13 kHz  ±0,5 dB
Output Level/Impedance (Rec Out):  500 mV/2,8 k Ω (FM 100% mod. 1 kHz)
AM Section
Tuning Range:  510 kHz - 1620 kHz
Usable Sensitivity:  250 µV/m
Selectivity:  24 dB
Signal-to-Noise Ratio:  50 dB
Image Response Ratio:  40 dB
Spurious Response ratio:  50 dB
Total Harmonic Distortion (400 Hz):  0,3%
Output Level/Impedance (Rec Out):  150 mv/2,8 k Ω (AM 30% Mod, 400 Hz) 
Power Supply:  110, 120, 220, 240 V AC, 50/60 Hz
Power Consumption:  400W
AC Outlet [{U}{C}{R} only]
Switched x 2 :  100 W {R}, 60 W {U}{C}
Unswitched x 1 :  200 W max.
Dimensions (W x H x D):  435 x 151 x 423 mm (17-1/8" x 5-15/16" x 15-5/8")
Weight:  12 kg (26 lb 7 oz)

I like 

Nakamichi IA-3

The Essential Features:
In the interest of musical resolution and sonic transparency only an input selector, a record output selector, a volume control, and a power switch are provided. Inputs are available for Tape, CD, Tuner and Aux.
The amplifier circuits are 100% discrete -  no ICs are used. All parts are of the finest quality. Voltage amplification is performed by a differential two-stage circuit.
The IA-3 power amplifier section is rated at 40 watts per channel (stereo) into 8 ohms. The oversized power supply and high-current output stage, however, result in considerable dynamic headroom, enabling the clear reproduction of demanding musical peaks.  The amplifier low-impedance drive capability is exceptional. Efficient dissipation of thermal energy is assured by heat sinks made of black almite.
Starting at the inputs, separate ground lines are maintained for the left and right channels, becoming common only at the speaker outputs. This through left/right ground isolation is especially important in the low-level stages and contributes to greatly enhanced stereo separation and imaging.

Conventional designs with monitor switches require a contact point in the signal path, and the constant load of a monitor output is detrimental to signal purity. The IA-3 takes a different approach the record output selector is not part of the main signal path and, hence, has no advers affect on sound quality.
The power supply section and audio circuits are on separate printed circuit boards to prevent any unwanted interaction.
The selectors, volume control, and input/output jacks are arranged to maintain the shortest possible signal path.
A heavy-duty chassis with a dual-plate bottom eliminates "ringing" and effectively shields the amplifier circuits from external interference.
The power transitors, volume control, and blocking capacitors are all high-grade components designed specifically for exacting audio applications.
The CD input jacks are gold-platted.
The front panel and the control knobs are made of heavy-gauge aluminum.
Screw-type terminals are provided for speaker connection.

Power Amplifier Section
Rated Power Output: 
40 watts per channel into 8 Ω (both channels driven, 20-20,000 Hz; 0,1%THD)
65 watts per channel into 4 Ω (DIN, both channels driven 1 kHz; 1%THD)
Dynamic Power Output:
57 watts per channel into 8 Ω
80 watts per channel into 4 Ω
Power Bandwitdth:  10 - 40,000 Hz
Frequency Response:  20 - 20,000 Hz +0, -1 dB; 10 - 60,000 Hz =0, -3 dB
Signal-to-Noise Ratio: 
better than 103 dB rated power (A-weighted,, input shorted)
better than 83 dB (A-weighted, input shorted , IHF-A-202)
Total Harmonic Distortion:  0,1% or less (8 Ω, rated power,, 20-20,000hz)
Peak Current Capability:  12 A
Preamplifier Section
Input Sensitivity/Impedance:  150 mV/20 k Ω
Output Level/Impedance:  150 mV/1 k Ω (Rec Out)
Power Requirement:  110, 120, 220, 240 V AC, 50/60 Hz
Power Consumption:  210 W max
Dimensions (W x H x D):  430 x 75 x 320 mm
Weight:  7 kg approx.

Acoustic Energy AE 1 classic

The AE1 Classic is modelled on the original AE1 from around 1990. our aim was, within the limitations of component supply and manufacturing, to make the AE1 Classic as close to identical as possible. That we didn't quite make it is only because, thanks to improved components and manufacturing consistency, the AE1 Classic is better.
The originsl AE! Introduced new techniques in almost every element of its design and construction, each one aimed at making a better nearfield monitor. It was, for example, the first professional monitor with a ceramic sandwich aluminium cone, the first to increase power handling by using the cone as a heat-sink, the first to incorporate a metal dome tweeter,, the first to feature a latex fibre/powder composite lined cabinet, and the first to demonstrate beyond doubt that a seriously small speaker could be a seriously capable monitor.
The AE 1 technical highlights feature in the Classic just as they did in the original. The bass/midrange driver is UK manufactured in house at Acoustic Energy using a spun aluminium cone only 0,2mm thick. The cone is hard anodised onn both side to create an immensely rigid sandwich component and then bonded to an aluminium voice-coil former. The intimate bond between metal former and cone means that the entire cone area is used for heat dissipation. As a result, and despite its small dimensions, the AE 1 driver offers generous power handling and suffers minmal compression.

Welcome though it is, power handling is not the primary reason for the choice of an aluminium cone. Aluminium's combination of light weight and rigidity means that cone break-up is delayed till well above the crossover frequency. And thanks to the aluminium cone, bass/mid driver and magnesium dome tweeter, the AE 1 Classic is one of very few speakers of any type that can genuinely claaim pistonic operation over the full audio bandwidth. The result is extraordinary tonal accuracy that reveals the shortcomings of most other monitors.
Near ideal drive unit performance however would mean little if the AE 1's cabinet panels sang along in sympathy. That they don't is thanks both to the inherent rigidity of the AE 1 construction and to the unique latex composite lining of the internal walls.

AE 1, First and Second
The E 1 was the first truly accurate, high power compact nearfield monitor. We believe 20 years later the AE 1 Classic is perhaps the only speaker to reach its predecessor's standards. The AE 1 Classic completes the award winning reference series, which features the AE 1 MkII and AE3 MkII.

Bass/Mid :  110 mm ceramic sandwich aluminium cone, 32 mm edge-wound voice-coil
Tweter :  32 mm magnnesium alloy dome
Crossover:  third order at 3 kHz
Power Handling:  compatible with amplifiers rated at up to 200 watts into 8 ohmm
Frequency Response:  70 Hz - 22 kHz ±3 dB
Sensitivity: 88 dB for 2,83 V at 1 m
Nominal Impedance:  8 Ω
Total Harmonic Distortion:  typically less than 0,3%, 200 Hz to 20 kHz
Power Compression:  less than 1 dB for 16 dB gain at 250 Hz
Dimensions (W x H x D):  295 x 180 x 255 mm
Weight:  8 kg (single speaker)

B&W DM 330i

Bowers and Wilkins DM330i
Stand-mount/Bookshelf loudspeaker system
Product Summary
The DM330i is a 2 1/2-way closed-box stand mount/bookshelf loudspeaker system.
Super sensitive, with high acoustical output yet affordable.
Technical highlights
Modal analysis techniques revealed a simple bonding technique of corner joints could improve rigidity and reduce coloration.
New thinking on crossover design has also led to the provision of higher safe power handling and fuse protection overload.
The driver chassis have non-magnetised castings for all the bass midrange units ensuring resonance free high-level sound of the highest amplitude.

Drive Units:
1 x 26 mm high-frequency driver with dome/coil construction of special polymide material
2 x 200 mm nominal piston dia and 26mm high temperature voice coil with critically impregnated composite short fibre cone
Frequency Response:   48 Hz to 20 kHz (± 3dB)
Sensitivity:  91 dB spl (2.83V, 1m)
Power Handling:  10W – 100W
Dimensions (H x W xD):  857 X 290x 320 mm
Finish:  American Walnut or Black Ash vinyl

Dual C809

The Dual C809 fulfills or exceeds the requirement of DIN 45 500 for domestic HiFi equipment. 
Tape Speed:  4,75 cm/s
Deviation from Correct Speed:  less than ±1%
Wow and Flutter:  weighted RMS :  less than ±0,07%
To DIN for reproduction only :  less than ±0,12%
To DIN for recording/reproduction :  less than ±0,16%
Frequency Response (ref-to DIN tolerances)
Fe Standard Tape :  20 -15,000 Hz
CrO₂ Tape :  20 - 15,000 Hz
FeCr Tape :  20 - 16,000 Hz
Distortion K3 at 333 Hz (ref.to 0 dB VU)
Fe Standard Tape :  less than 0,7 %
CrO₂ Tape :  less than 1,5 %
FeCr Tape :  less than 0,7 %
Signal-to-Noise Ratio (weighted)
With Dolby NR
Fe  Tape : better than 63 dB
CrO₂ Tape : better than 63 dB
FeCr Tape : better than 65 dB
Without Dolby NR
Fe Tape :  better than 56 dB
CrO₂ Tape : better than 56 dB
FeCr Tape :  better than 58 dB
Channell Separation at 1000 Hz
Between Stereo Channels :  better than 30 dB
In Oppositie Direction :  better than 70 dB
Erasure at 1000 Hz :  better than 70 dB
Oscillator (push-pull oscillator):  80 kHz
Inputs ( Sensitivity at 0 dB VU)
Microphone :  0,2 mV/10 k Ω
DIN Connector :  0,6 mV/10 k Ω
RCA Jack :  65 mV/ 45 k Ω
DIN Connector :  560 mV/8 k Ω
RCA Jack :  580 mV/1,0 k Ω
Headphones :  4 - 2000  Ω adjustable
Tape Motion Monitoring:  Electronic
Complement:  2 Ics; 30 Transistors; 13 Diodes; 2 LED's; Z-diode; 1 Silicon bridge rectifies; 2 G-Fuses 400 mA slow-blow
Power Requirements:  100 -125 V / 220 - 240 V, 50/60 Hz
Power Consumption:  approx. 10 Watt

Dual C 939

The more experience you've had with tape decks, the more you're likely to appreciate the Dual C939's performance and versatility. Apply the most demanding musical tests; sustained piano tones for flutter; extreme highs and lowes for frequency response; soft passages for Signal-to-Noise ratio - and you will hear no diference between the original disc and tape made on the 939. all of which brings to life the 939's impressive specifications for wow and flutter (0,05%), Signal-to-Noise (65 dB) and frequency response (20-17,000 Hz). Now we'd like to take you through the 939's astonishing array of design and operating features.
Auto/reverse playback, bi-directional record. The 939 reverses automatically in play-back - a C-90 will play 90 minutes without interruption. There's continuous play too. Recording is bi-directional. When the tape reaches the end, youu just reverse direction.
With any other deck you either live with unwanted sounds on a tape or erase them abruptly - without hearing what you're doing until it's too late.
With the 939's unique fade/edit control you can fade out those annoyances gradually, smoothly and permanently. And then fade back into the music. While listening. Because it's all done during playback.

Drive system and tapeheads like no other.
Dual's powerful Continuous-Pole /synchronous motor,, two capstans and two drive belts maintain speed accuracy within 0,5% . A C-90 cassette fast-winds in lust over a minute, the time other decks need for a C-60. hard permalloy tapeheads are used for their extended life and superior magnetic linearity. The four-track record/playback head switches electronically when the tape changes direction, it never shifts position. The result; perfect tape alignment in both directions at all times.

LED Record-Level Indicators
Meter needles can't move fast enough to keep up with musical signals. Which is why the 939 uses instantaneous reacting LED record-level indicators. And they lilt to the best viewing angle.

The Dual C939 meets or exceeds the requirement of DIN 45 500 for domestic HiFi equipment. The data given base upon the current DIN reference tapes.
Tape Speed:  4,75 cm/s
Deviation from Correct Speed:  less than ±1%
Wow and Flutter:  weighted RMS :  less than ±0,07%
To DIN for reproduction only :  less than ±0,10%
To DIN for recording/reproduction :  less than ±0,10%
Frequency Response (ref-to DIN tolerances)
Fe Standard Tape :  20 -14,000 Hz
CrO₂ Tape :  20 - 16,000 Hz
FeCr Tape :  20 - 17,000 Hz
Distortion K3 at 333 Hz (ref.to 0 dB VU)
Fe Standard Tape :  less than 1,2 %
CrO₂ Tape :  less than 1,8 %
FeCr Tape :  less than 1,0 %
Signal-to-Noise Ratio (weighted)
With Dolby NR
Fe  Tape : better than 63 dB
CrO₂ Tape : better than 63 dB
FeCr Tape : better than 65 dB
Without Dolby NR
Fe Tape :  better than 53 dB
CrO₂ Tape : better than 56 dB
FeCr Tape :  better than 58 dB
Channell Separation at 1000 Hz
Between Stereo Channels :  better than 30 dB
In Oppositie Direction :  better than 60 dB
Erasure at 1000 Hz
Fe Tape :  better than 70 dB
CrO₂ Tape : better than 65 dB
FeCr Tape :  better than 70 dB
Oscillator (push-pull oscillator):  80 Hz
Inputs ( Sensitivity at 0 dB VU)
Microphone :  0,30 mV/10 k hm
DIN Connector :  0,45 mV/4,7 k Ω
RCA Jack :  70 mV/ 82 k Ω
DIN Connector :  0 -700 mV/1,8 k Ω
RCA Jack :  0 - 700 mV/1,8 k Ω
Headphones :  4 - 2000 k Ω adjustable
Fast Winding:  C-60 less than 60 sec.
Complement:  4 Ics; 49 Transistors; 30 Diodes; 1 Darlington photo cell; 28 LED's
Power Requirements:  100 -125 V / 220 - 240 V, 50/60 Hz
Power Consumption:  approx. 35 VA

I like 

Akai GX 260D

The GX 260D means the machine is fitted with Akai's unique Glass and Crystal Ferrite head. This head is completely unique to Akai. The core of the head is  a "single crystal" gem set in pure glass of terrific hardness. Because the gem set in pure glass of terrific hardness. Because the gem is a single crystal, it has no composite particles that can break off and damage he head. (Inn a way, it's rather similar to the jewel action in a watch - except that Akai would be the only watch - maker to use it.)
So, the head remains wear-free for life. In fact, Akai guarantee it. If the GX head on your Akai machine wears out in normal use during the lifetime of the machine, we will repace it without charge.
And in the meantime, the GX head gives you outstanding performance because the head and the tape are kept in perfect contact at all times - even high frequency distortion is very greatly reduced.

The GX 260D has four heads - 2GX recording/ erase heads and 2 GX playback heads. It features automatic or manual revers for both recording  and playback.
It has 3 motors - one self-lubricating hysteresis synchronous capstan drive motor, two eddy-current outer-rotor reel drive motors. The advantage of the centre capstan drive motor is that it ensuress identical performance in both tape directions.
The GX 260D offers you line output  level control. It lets you add echo effect to any recording. And, of course, it has all the facilities for sound-on-sound, sound-with-sound, and microphaone/line mixing.
There's also a yape/Source montor,  a Tape Selector Switch and Automatic  shut-off.

Track System:  4-track, 2-channel stereo/monaural
Reel Capacity:  up to 7" reel
Tape Speed:  7-1/2 and 3-3/4 ips
Wow and Fluter:  less than 0,06% WRMS at 7-1/2 ips; less than 0,1% WRMS at 3-3/4 ips
Frequency Response: 
Low Noise Tape :
30 - 26,000 Hz (±3 dB) at 7-1/2 ips
30 - 20,000 Hz (±3 dB) at 3-3/4 ips
Regular Tape :
30 - 23,000 Hz (±3 dB) at 7-1/2 ips
30 - 18,000 Hz (±3 dB) at 3-3/4 ips
Distortion:  less than 1,2% (1,000 Hz, 0 VU)
Signal-to-Noise Ratio:
Activated Tape Selector Circuit :  Better than 57 dB
Inactivated tape Selector Circuit :  Better than 54 dB
Erase Ratio Cross-Talk:
Mono :  better than 60 dB
Stereo :  better than 45 dB
Bias Frequency:  100 kHz
Heads:  two GX recording/erase combination heads, two GX playback heads
One :   4/8-pole self-lubricating hysteresis synchronuous capstan drive motor;
Two :  Eddy-current outer-rotor reel drive motors
Fast Forward / Rewind Time:  75 sec using 1200 ft tape
Output Jacks:
Two Line :  1,23 V, 0 VU/100 Ω (required load impedance more than 20 k Ω)
One Phono :  30 mV/ 8 Ω
Input Jacks:
Two Line :  50 mV
Two Microphone :  0,3 mV/4,7 k Ω
DIN Jack:  0,5 V/25 mV
Power Requirements:  100 V to 240 V AC, 50/60 Hz
Dimensions (W x H x D):  17,5 " x 18,6" x 8,9"
Weight:  45,8 lbs

A&R Cambridge T21

The T21 Stereo FM Tuner
The qualities of the A60 amplifier series demand a tuner that is a complete partner. The T21 is that partner, an ideal match in looks, performance and price.

Great care has been taken in the design of the sound circuitry of the T21 to produce an unusually flat frequency response over the critical listening bandwidth. A "birdie" filter, fitted before the stereo decoder, considerably reduces the unpleasant whistles ("birdies") caused by closely positioned stereo broadcasts it also compensates for phase errors in previous stages which would otherwise add to distortion and crosstalk. A highly efficient ,ultiplex filter removes the 19 and 38 kHz high frequency tones produced by the stereo decoder circuitry, preventing damage to loudspeakers and interference with the bias oscillator in a tape recorder.

Overall, our design and production standards have been carefully maintained with the T21 tuner. We beliwve it is the perfect complement to our range of high performance, value-for-money sound equipment.
T21 also included in the tuning window is a single red LED as a stereo beacon. Tuning can be carried out by either the manuall tuning control or one of the five preset push buttons. Full station search with continuously variable tuning is provided by the rotary knob which has a pleasant and useful flywheel action. For the more frequently used stations each of the five buttons can be individually preset with the controls at the rear of the tuner. A mute facility is provided to remove background noise between the stations. To ensure that a station, once selected, remains accuraattely tuned in, an AFC (automatic frequency control) is fitted.

The  T21 can be used with any amplifier including of course, the A60 itself. A level controll knob on the rear of the tuner allows unwelcome variation in the output volume between the tuner and, say, a record deck to be equalised. Thus only minimal adjustment of the amplifier's volume control is ever needed. Both 75 Ω and 300 Ω balanced serial sockets are provided together with tuner matching plugs, allowing easy connection to all standard FM aerial systems.

Tuning Scale:  21 matched red LEDs in steps of 1 MHz, a gradual changeover in light intensity between adjacent LEDs allows frequency readings of typically 0,2 MHz to be achieved.
Tuning Range:  87,5 - 108,5 MHz
Signal Strength Meter:  bargraph scale using 5 LEDs, 2 red and 3 green
Tuning Meter:  3 LEDs, red-green-red
Stereo beacon:  single red LED
Aerial Inputs:
Socket for 75 Ω and 300 Ω antenna
Sensitivity (IHF):  1,3 µV
-3 dB Limiting Point :  10 µV
Capture Ratio:  1,5 dB
Alternate Channel Selectivity:  better than 60 dB
Repeat Spot Suppression:  better thann 80 dB
IF Rejection:  better than 80 dB
AM Suppression:  better than 50 dB 
(ref. 75 kHz deviation, 30% AM at 400 Hz, aerial signal  10 µV-10 mV)
Signal-to-Noise Ratio (CCIR/ARM weighted):
Mono :  better than 70 dB
Stereo :  better than 68 dB
Pilot Tone Suppression :  better than -50 dB
Subcarrier Suppression:  better than -40 dB
Total Harmonic Distortion (1 kHz):
Mono :  better than 0,15% (typically 0,08%)
Stereo :  better than 0,25% (typically 0,15%)
Channel Separation:  better than 40 dBf
Frequency Response:  20 Hz - 12 kHz  ±0,5 dB ( typically -3 dB at 15 kHz)
Channel balance:  within ±1 dB
Output Level:  continously variable 10 mV- 1 V at full deviation
Output Impedance:  less than 1 k Ω
Recommended Load:  better than 10 k Ω
Power Supply;  200 - 250 V  AC, 6 VA maximum; (or  100 - 120 V AC)
Deimensions (W x H x D):  450 x 60 x 240 mm (17-3/4" x 2-3/8" x 9-1/2")
Weight (net):  3,3 kg (7,3 lb)

TEAC A-X5030

Integrated Stereo Amplifier A-X5030
High-power drive capability
Switchable subsonic filter
-20 dB muting switch
Loudness compensation switch
Center-detented bass and treble tone controls
Balance control
Dual speaker terminals and independent speaker A/B switches
Heavy-duty binding-post speaker terminals
Large insulator feet.

Another example of TEAC dedication to delivering the finest possible quality in these amplifiers is the fact that each unit is individually calibrated for optimum performance.
In the A-X series amplifiers, the output stage idling current is determined by a precision trimmer rather than the usual fixed resistor. This is adjusted to provide optimum idling current - and therefore an absolute minimum of crossover distortion - during the final testing and inspection stage. You can rest assured that the amplifier you receive is fine-tuned to deliver super sound quality.
All-Mechanical Short-Path Signal Switching
Many modern amplifiers use semiconductor switches to control signal routing. These like any other electronic part, can degrade signal quality. TEAC has used only top-quality mechanical switches ensuring reliable, distortion-free signal routing. Furthermore, switches handling low level signals are positioned as close as possible to the corresponding rear-panel terminals to minimize the signal path length and are remotely controlled via the panel knobs. This means that noise and interference pickup is minimized for extra signal purity.
 Source Direct Switch
When you want an extra margin of signal purity, the Source Direct switch can be engaged to bypass the tone, balance, loudness controls, muting and subsonic filter controls, giving you the shortest, most direct signal path possible for all input sources.
Versatile Input and recording Capability
Independent input and Rec selectors let you monitor one source while simultaneously recording another. The Rec selector also offers tape-to-tape recording capability. The A-X5030 accept of 6 base input sources like; phono, tuner, CD, tape 1/DAT, tape 2, AUX, and additionally features Adapter/Tape 3 terminals that can be used to connect a third tape deck or an external adapter such as a graphic equalizer or surround processor. The A-X5030 also features a high-performance internal MC phono cartridge head amplifier and an MM/MC phono selector switch.
Heavy-Duty Binding-Post Speaker Terminals
Since speaker cables can have a significant effect on the sound, the TEAC amplifiers are equipped with heavy-duty binding-post terminals that will easily accept high-quality speaker cables while providing solid reliable contact.

Continuous Power Output (RMS):
At 8  :  75 W + 75 W (20 - 20,000 Hz, 0,02% THD)
At 4  :  100 W + 100 W (20 - 20,000 Hz , 0,04% THD)
DIN Power Output:
At 8  :  85 W + 85 W (1 kHz)
At 4  :  120 W + 120 W (1 kHz)
Dynamic Power Output:
At 8  :  100 W + 100 W
At 4  :  150 W + 150 W
Total Harmonic Distortion (Continuous Rated Output Power):
At 8  :  0,007% (1 kHz)
At 4  :  0,01 % (1 kHz)
Input Sensitivity/Impedance:
Phono (MM) :  2,5 mV/ 47 k Ω
Phono (MC) :  0,25 mV/100 Ω
CD, Tuner, Aux, Tape :  150 mV/30 k Ω
Signal-to-Noise Ratio (IHF--A):
Phono (MM) :  80 dB (5 mV)
Phono (MC) :  67 dB (0,5 mV)
CD, Tuner, Aux, Tape :  101 dB
Frequency Response:
Phono (RIAA) :  20 - 20,000 Hz ±0,5 dB
CD, Tuner, Aux, Tape :  5 - 100,000 Hz -3 dB
Dimensions (wxhxd):  435 x 155 x 354 mm
Weight:  10,5 kg

NAD 6340

Cassette Deck
Dolby HX-Pro and DYNEQ: 
Dyneq varies the record equalization to prevent over saturatio when strong high frequency transients occur. HX PRO varies the bias supplied to the bias supplied to the tape during recording to maintain optimum high frequency at all times, thus making a much more accurate reproduction of your source. Note:  HX-pro and DYNEQ are compatible for playback with all cassette decks, including car decks.
Car Circuit: 
Boosts quiet passages in the music without altering the loud passages, making a more practical tape for car or portable players. It also adds equalization for the car environment.
Play Trim:
Developed by Dolby laboratories with NAD, Play Trim compensates for high frequency loss before Dolby NR, restoring highs withput increasing noise. Example: Take an old tape with dulled highs and turn the Play Trim knob and note the restored highs.
Dolby B & C
Full Logic Transport

Speed Accuracy:  +1%
Wow and Flutter: 
less than 0,06% JIS wtd RMS
less than 0,1% DIN wtd. Peak
Frequency Response:  30 Hz - 19 kHz +3 dB (MPX filter Off)
MPX Filter Response:  flat within 1 dB to 15 kHz
Harmonic Distortion:  varies with recording level typically less than 0,3% at -10 dB
Total Harmonic Distortion at 0 dB:
Normal Tape :  less than 1,0 %
CrO₂, Metal Tape :  less than 1,5%
Signal-to-Noise Ratio (ref.3% T.H.D. at 333 Hz CC1R/ARM weighting):  57 dB
Dolby off :  75 dB
Dolby B :  67 dB
Dolby C :  77 dB
Channel Separation:  45 dB at 1 kHz (38 dB broadband)
Erasure:  better than 70 dB at 1 kHz
Input Sensitivity /Impedance:  40 mV/10 k Ω
Maximum Input level:  25 V
Output Level at 0 dB:  500 mV
Output Impedance:  1000 Ω
Power Requirement:  120, 220, 240 V AC 50/60 Hz
Power Consumption:  22 W at 120 V AC
Dimensions (W x H x D):  420 x 122 x 270 mm (16,5" x 4,8" x 10,6")
Weight (net):  4,5 kg (9 lb 15 oz)