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

Sony PS-3750 turntable

Direct-drive Turntable System
Direct drive system with BSL 9Brush and Slotless) DC servo-controlled motor
Electronically controlled speed selection for 33-1/3 and 45 rpm with pitch control
Buil-in stroboscope and engraved strobe markings on the platter rim
Precision machine finished aluminium alloy platter with resonance reducing undercoating
Newly designed record mat features air-damped record cushions
Highly sensitive statically balanced tonearm with plug-in universal headshell
Shock-mounted static balance counterweight with direct-reading stylus force gauge
Remote viscous-damped cueing
Rotatable armrest for easy tonearm balancing
Low capacitance phono cable and separate ground wire
Removable hinged plastic dust cover
Adjustable feet with rubber anti-feedback isolation
Complete with 45 rpm adapter, cartridge mounting screws and spacer

Platter:  314 mm 912-3/8 inches) aluminum alloy diecast
Motor:  DC brushless motor
Drive System:  Direct drive
Speeds:  3-1/3 and 45 rpm
Pitch Control:  ±4%
Wow and Flutter:  less than0,03% WRMS
Signal-to-Noise Ratio:  better than 70 dB (DIN-B)
Type:  Statically balanced, universal
Pivot to Stylus Length:  216,5 mm 98-1/2 inches)
Overall Arm length:  300 mm 911-7/8 inches)
Overhang:  16,5 mm (21/32 inchees)
Tracking Error:  within +3°, -1°
Tracking Force Adjustment Range:  0- 3 g
Shell Weight:  7,5 g
Cartridge Weight Range:  4 - 13 g (without extra weight)
Power Requirements:  120 V, 60 Hz
Power Consumption: 10 W
Dimensions (W x H x D):  445 x 155 x 365 mm (17-5/8" x 6-1/8" x 14-3/8")
Weight (net):  9 kg ( 19 lb 13 oz) 

Sanyo TP-1005 turntable

PLL Servo Belt Drive Stereo Turntable
Electronic speed control
s-shaped tonearm
Plug-in Headshell
Calibrated Counter weight for Stylus Force Adjustment
Adjustable Anti-skating
Viscous-damping Cueing
Shock-absorbent Feet

Motor:  DC motor
Drive System:  Belt drive
Speeds:  33-1/3 and 45 rpm
Wow and Flutter:  0,05% WRMS
Signal-to-Noise Ratio:  better than 60 dB
Turntable Platter:  292 mm (11-1/2" diameter
Tone Arm:  Static S-shaped balance type
Tracking Error:  ±1,5°
Stylus Pressure Force Range:  0 - 3 g
Cartridge:  magnetic steeo (MG-35D)
Stylus:  0,6 mil diamond stylus (ST-35D)
Stylus pressure:  1,5 - 2,5 g
Frequency Response :  20 - 20,000 Hz
Overhang:  15 mm
Channel Separation:  better than 20 dB
Power Source:  AC 100 - 120 V, AC 220 - 240 V; 50/60 Hz
Power Consumption:  6W
Dimensions (W x H x D):  440 x 140x 360 mm (17-3/8" x 5-1/2" x 14-1/4")
Weight:  4,1 kg (9 lbs)

Toshiba ST-335 MkII tuner

The Toshiba ST-335 MkII is an AM/FM stereo tuner featuring a stereo beacon, a three-position LED FM center channel tuning indicator, a five-step LED signal Strength/ AM tuning indicator, and a record calibration (Rec Cal) tone output for pre-adjustment of the input level to a tape recorder. The record calibration output is 6 dB below (-6 dB) the output level from a 100% modulated FM transmitter. The FM center channel tuning "meter" consists of a two yellow LED s flanking a gree LED; optimum tuning is attained when only the green LED is lit. However, tuning is relatively broad in the 'green range", and distortion and separation values might vary from our measurements. The output is provided by two "patch cords" with phono plugs, approx 1 meter in length.
The FM pilot leakthrough is relatively high and a recorder's MPX filter must be used when making recordings from FM stations. 

Sensitivity (IHF):  2,0 µV (11,2 dBf)
Selectivity:  60 dB
Capture Ratio:  1 dB
Image Rejection Ratio:  50 dB
Spurious Rejection:  70 dB
IF Rejection Ratio (98 MHz):  80 dB
Signal-to-Noise Ratio (IHF)
Mono :  73 dB
Stereo :  65 dB
T.H.D. (1 kHz)
Mono :  0,2%
Stereo :  0,4%
Stereo Separation (1 kHz):  40 dB
FM Frequency Response :  30 Hz - 15 kHz (-1 dB)
Output level:  500 mV
AM Suppresion Ratio:  45 dB
AM Sensitivity:  300 µV/m
Dimensions (W x H x D):  420 x 96 x 257 mm (16,5" x 3,8" x 10,1")
Weight:  3,4 kg (7,5 lbs)

Scott PS-18 turntable

Semi-Automatic Turntable
The Scott PS-18 is a belt-driven two-speeds semi-automatic record player complete with factory installed pickup. Overall performance and soun quality is about average for the price, though the system is sensitive to external shock and vibration. The motor starts when the tonearm is moved off its rest. At the end of play the tonearm recycles to the rest and the motor turns off. The tonearm has a micro-adjust counterweight that serves as an 0 - 4 gram VTF (vertical Tracking Force) adjustment calibrated in 0,5 gram increments. There is a calibrated anti-skate. The pickup rated for 1,5 to 3 grams VTF, is factory installed in a fixed headshell. The stylus overhang gauge is a reference mark on the shell which isn't sufficiently accurate for user-installed pickups. The tonearm rest has a positivie user-applied lock that prevents accidental displacement of the tonearm from its rest, which might result in stylus damage. The PS-18 we tested was from the first production run at the factory. Subsequent units are to be delivered with a universal headshell mount to give the user more flexibility in cartridge selection and easier installation.

Speed select
Tonearm lift
Vertical Tracking Force
Turntable Performance
Line Voltage Immunity:  Total (90 to 140 volts)
Wow and Flutter:  0,07% (average);  0,1% (peak)
Tracking Force Calibration :  accurate to 0,25 grams
Output Cable Capacitance:  150 pF
Pickup performance:
Frequency response Limits:  +5/-1 dB
Frequency Response:  20 to 20,000 Hz
Channel Balance:  1 dB
Stereo Separation:
At 1,000 Hz :  20 dB
At 15,000 Hz :  15 dB
Dimensons (W x H x D):  17,25" x 5,5" x 13,75"
Weight: 15 pounds

Crown FM 1 tuner

FM Stereo Tuner
An FM only stereo tuner with phase-locked loop digital tuning and LED metering readouts. All tuning functions are touch-controlled for no-moving-parts operation. The memory function allows the pre-setting of five favorite stations for instant recall. The scan search feature allows the listener to sweep up and down the dial, stopping either at every active station or only those broadcasting in stereo automatically. The variable muting control allows the user to set the tuner to receive only signals of sufficient strength to assure noise-free reception. All phases of operation are handled smoothly and facilitate the highest order of tuning accuracy and convenience. Ther is LED  metering for multipath and signal strength variable interstation muting control, selectable stereo de-emphasis and a multiplex filter.

Tuning Range:  88,1 to 107,9 MHz
Antenna Inputs:  300 Ω balanced; 75 Ω unbalanced
Intermadiate Frequency:  10,7 MHz
Sensitivity:  10,8 dBf (IHF usabla)
Quieting:  0,6 mV (75 Ω) for 30 dB mono quieting;  36 dBf for 50 dB stereo quieting; 10,8 dBf for 50 dB mono quieting
Signal-to-Noise Ratio:
Mono :  70 dB below 100% modulation at 65 dBf reference level
Stereo :  65 dB below standard stereo modulation at 65 dBf reference level
Hum and Noise:  65 dB below 100% modulation at 65  dBf reference level. Minimum volume hum and noise is 90 dB below reference
Total Harmonic Distortion:  at 1000 Hz 65 dBf 100% modulation
Mono :  0,1%
Stereo :  0,09%
Capture Ratio:  2 dB at 65 dBf
Alternate Chanel Selectivitty:  75 dB at 25 dBf
Frequency Response:  30 Hz to 15 kHz ±0,5 dB
Stereo Separation:  45 dB at 1 kHz; 35 dB aat 10 kHz
Image Response Ratio:  better than 114 dB
Spurious Response Ratio:  better than 114 dB
IF Response Ratio:  better than 114 dB both balanced and unbalanced
RF Intermodulation:  65 dB
AM Suppression Ratio:  better than 73 dB at 25 dBf
Subcarrier producct Ratio:  65 dB
SCA Rejection Ratio:  72 dB
300 Ω Balanced Antenna Input - push button quicj connect
75 Ω Unbalanced Input - F type
Composite - PIN jack
Multipath - PIN jack
Left Channel variable and fixed output - PIN Jack
Right Channel variable and fixed output - PIN Jack
Display:  7 segment red LED Frequency readout
Red LED Stereo indicator
20 LED Analog dial green dot display
10 LED Signal Strength green bar display
10 LED Multipath amber bar display
Power Requirements:  120 V or 100, 200, 220, 240 V AC , 50/60 Hz
Power Consumption:  10 watts
Dimensions (W x H x D):  483 x 133 x 381 mm (19" x 5-1/4" x 15")
Weight:  7 kg (15,5 pounds)

Denon DP-30L turntable

Servo controlled Direct-drive Auto-lift turntable
The Denon DP-30L is an electronically controlled direct drive two speed record player complete with integral base and dust cover. The pickup is provided by the user.
Overall performance is exceptionally good; high performance pickups seem to deliver a "little bit extra", and resistance to external shock and vibration is unusually high, even at low tracking forces. No stylus overhang gauge is provided; the user must make the adjustment using a ruler, which can lead to stylus damage. There is really no good reason why a record player of this quality and price is not provided with an overhang gauge, which costs a few pennies, at most.
There are controls for main power, 33/start, 45/start, speed adjust (pitch) and stop. 33 and 45 full time illuminated strobes are provided. The tonearm is manually positioned on the record. At the end of play an optical sensor causes the tonearm to lift and motor to stop. Alternately, pressing stop during play will cause the tonearm to lift and the motor to stop. Pressing a speed selector control restarts the motor and lowers the tonearm. The tonearm has a micro-adjust counterweight that also serves as an 0-3 gram VTF calibrated in 0,1 gram increments. There is a calibrated antiskate. The pickuup mounts in a universal headshell.
Auto-lift mechanism with non-contact record-end sensor
Newly developed auto arm lifter functions with smoothness and stability
Trim and slim profile with up-front control arrangement
Detects speed with exclusive magnetic recording system
Achieving outstanding anti-howling characteristics through a cabinet made of new compound
Remarkably low (-75 dB) DIN-B rumble -Quiet smooth running AC motor

Drive System:  Dirct-drive
Motor:  AC servomotor
Speed:  33-1/3 and 45 rpm
Variable Speed Adjustment Range:  over ±3%
Wow and Flutter:  less than 0,018% WRMS
Signal-to-Noise Ratio:  better than 75 dB (DIN-B)
Starting Time:  less than 1,5 sec to reach 33-1/3 rpm nominal speed
Speed Control System:  Servo controled by frequency detection
Turntable Platter:  Diecast aluminium 300 mm diam.
Weight:  1,5 kg
Moment of Inertia:  190 kg-cm² (including turntable mat)
Type: S-shape static balance with automatic arm lift
Effective length:  220 mm
Overhang:  16 mm
Tracking Error:  within 3°
Stylus Force Range:  0 - 2,5 g/rot (1 division is 0,1 g) direct reading
Acceptable Cartridge Weight:  5 - 10 g (with head shell provided)
Weight of Headshell:  8 g 9excluding screws, nuts and spacer)
Shell Connector: FIA standard 4P connector
Arm Lifter:  Servo controlled by angular control motor
Power Supply:  AC 120 V at 60 Hz, AC 200, 220, 240 V at 50 Hz
Power Consumption:  15 W
Dimensions (W x H x D):  450 x 140 x 403 mm ( dust cover closed)
Weight:  9,5 kg 

Denon PMA-630 amplifier

The Denon PMA-630 is a stereo integrated amplifier FTC rated for 8 ohms at 80 watts RMS per channel, 20 to 20,000 Hz  at less than 0,01% T.H.Dbetter than thouch a dual range (20 Hz and 40 Hz) subsonic filter and loudness compensation are provided, there are no conventional tone controls. Tone equalization, if desired can be provided through an optional accessory equal izer, such as a graphic-type equalizer, for which "break in" preamplifier-poweramplifier connections are provided on the rear. A shorting bar normally connects the preamp and amplifier. To use an accessory equalizer, the shorting bars are simply pulled out, thereby "breaking" the signal path for the equalizer. Other features include automatic dubbing from and to either of two recorders, a recorder output disconnect (labled Rec out) which is supposed to avoid some effect of the recorders on sound quality (thogh we could not measure non hear  any deleterious effect of the recorders on the speaker sound), and an output hold-off that prevents power supply turn-on transient from being fed to the speakers. The unit is in a metal cabinet. Three AC convenience outlets are provided.
Pre-amplifier equipped power amplifier that leads the cartridge output to the speaker by way of a simple signal route
Pure complementary circuits
Low distortion high stability DC power amplifier
High output, High gain equalizer amplifier
Power section that employs a powerful power transformer and large capacity condensers
Reduction of output impedance through the adoption of the relay driving system (damping factor: 80 upward)
Rec-out "Off" function

Main Amplifier Section
Type:  pure complementary push-pull system DC circuit
Rated Output (both channels driven)
From 20 Hz to 20 kHz :  80 W + 80 W RMS at each channel (T.H.D., 0,008% at 8 Ω)
At 1 kHz :  80 W + 80 W RMS at each channel (T.H.D., 0,01% AT 4 Ω)
Total Harmonic Distortion:  LES THAN 0,01%
Intermodulation Distortion:  less than 0,005% (at equivalent rated output)
Less than 0,005% (at 1 watt output)
Power bandwidth:  5 Hz to 100 kHz (IHF, T.H.D. 0,05%)
Transmission Characteristic:  DC to 100 kHz +0 -1 dB (at 1 watt output)
Input Sensitivity/Impedance:  320 mV (RMS)/100 k Ω
Output Impedance:  less than 0,09 Ω
Output Terminals Speaker:
A & B, 4 to 16 Ω load
A + B, 8 to 16 Ω load
Pre-amplifier Section
Max. Output:  25 V (at 50 k Ω , T.H.D. 0,01%)
Rated Output:  320 mV
Total Harmonic Distortion:  0,003% (at 10 V output)
Input Sensitivity/Impedance: 
Disc 1 and 2 :  2,5 mV/ 50 k Ω
Tuner ;  320 mV/ 30 k Ω
Aux, Tape :  320 mV/ 30 k Ω
Maximum Allowable Input
Disc 1 and 2 :  200 mV 1 kHz
RIAA Deviation:  less than ±0,2 dB (20 Hz - 20 kHz)
Signal-to-Noise ratio (IHF, A network)
Disc 1 and 2 ;  better than 86 dB (input terminal shorted)
Tuner, Tape, Aux :  better than 112 dB (input terminal shorted)
Filter Characteristic:
Subsonic :  20 Hz (6 dB/oct); 40 Hz (6 dB/oct)
Loudness Control Characteristic
Low Range:  100 Hz +9 dB
High Range:  10 kHz +5 dB
Power Source:  AC 120 V at 60 Hz or AC 220 V at 50 Hz
Power Consumption: 215 W ( at Ac 120 V) or 445 W (at AC 220 V)
AC outlet (USA and Canada)
Unswitched :  250 W max total
Switched ;  100 W max
Dimensions (W x H x D):  434 x 145 x 390 mm (17-5/64" x 5-45/64" x 15-23/64")
Weight:  16 kg (35,3 lbs)

Toshiba SR-B150 turntable

Semi Automatic Belt Drive Stereo Turntable
4-pole AC synchronous motor
Straight  tone aem with antiskating
Oil-damped cueing
Anti-resonance cabinet
Magnetic cartridge (SR-B152)

Type:  Belt-drive, Semi-automatic
Motor: 4-pole synchronous
Speeds:  33-1/3 and 45 rpm
Wow and Flutter:  0,07%
Signal-to-Noise Ratio:  60 dB
Plater diameter:  310 mm
Tone -arm:  Straight-type arm with carbon glass fibre
Tracking Error:  ±2°
Cartridge:  C-320 M Moving Magnet
Stylus:  0,6 mil diamond
Dimensions (W x H x D):  420 x 130 x 380 mm (16,6" x 5,1" x 14.9")
Weight:  4,1 kg (9,0 lbs)

Toshiba SR-A100 turntable

Semi Automatic Belt Drive Stereo Turntable
4-pole AC synchronous motor
High quality tone aem with antiskating
Oil-damped cueing
Full acoustic damping
Magnetic cartridge (SR-A102)

Type:  Belt-drive, Semi-automatic
Motor: 4-pole synchronous
Speeds:  33-1/3 and 45 rpm
Wow and Flutter:  0,06%
Signal-to-Noise Ratio:  65 dB
Plater diameter:  310 mm
Tone -arm:  S-shape-type arm
Tracking Error:  ±2°
Cartridge:  C-44 Induced  Magnet
Stylus:  0,6 mil diamond
Dimensions (W x H x D):  422 x 130 x 359 mm (16,6" x 5,1" x 14.1")
Weight:  4,5 kg (9,9 lbs)

Sony PS-X555ES turntable

The linear tracking tonearm is a major technological achievement in turntable design that has recently become both highly successful and quite popular. The reason for its nearly universal appeal is simple - it plays records exactly as they were originally cut, thereby eliminating tracking error, and improving both stereo separation and overall sonic fidelity. Unfortunately, despite its benefits, the linear tracking tonearm alos produces an unwanted (and often audible) side effect - resonance. The Sony PS-X555ES uses microcomputer technology to control resonance.

The Problem of Low Frequency Resonance
A conventional tonearm pivots at a stable, reinforced point. By contrast, the linear tracking tonearm moves along the groove towards the center of the disc as it plays. This means that it lacks a rock-solid foundation. Since this is the key to fighting the low-frequency resonance that's fairly common during disc playback, linear tracking tonearms are prone to this type of distortion.
Resonance can actually be quite disturbing in a listaning situation - its manifestations include distortion, rumble, howl, and an overall dulling of the musics impact. It's a serious problem with all linear tracking turntables - except those equipped with Sony's unique Biotracer tonearm. The Sony Biotracer is the first - and to date, the only - linear tracking tonearm that effectively combats the effects of low-frequency resonance.

Biotracer Technology for Improved Performance
How  does the PS-X555ES control resonance? It thinks. The Biotracer tonearm of the PS-X555ES is a dynamic device that is constantly driven by two microcomputer controlled motors. When the microcomputer senses any variation from the correct tonearm position, it instantly alerts the motors 9one for horizontal motion, one for vertical), and instructs then to adjust the tonearm's motion. Not only does this ingenious system relieve resonance problems associated with the linear tracking design, it also helps combat distortion caused by warps and eccentricities in the disc itself. And previously annoying imperfections such as tonearm skating and improper stylus force adjustments are automatically corrected as well.
The Biotracer Supports Freedom of Choice
And the Biotracer does still more. With most turntables, your choice of cartridges is greatly limited - the tonearm accepts only a narrow range of cartridge mass and compliance. Butthat's not the case with the Biotracer. Because it is so effective in overcoming low-frequency resonance, the Biotracer permits you to install just about any cartridge you like. With most turntables, the choice of cartridge must be based on the equipment - with the PS-X555ES, you can select your cartridge according to its sonic characteristics.

Incorporates Many Other Design Innovations
Furthermore, all the special technology that's made Sony turntables so popular is also found on the PS-X555ES. That includes our Brushless Slotless (BSL) motor, recognized for its accuracy and reliability. Plus, Sony's quartz lock direct drive with magnedisc servocontrol ensures rotational precision. And height-adjustable gel-filled feet, combined with Sony's non-resonant SBMC base, resist acoustic feedback.
Naturally, all the convenience and performance features that have made the linear tracking design so popular are included in the PS-X555ES. For example, you can control the movement of the tonearm without ever raising the dust cover, and without risking damage to the record or the stylus - cueing and indexing are accomplished with front-panel feather-touch controls.

Tonearm Section
Tonearm Type:  Tangential Biotracer
Effective length:  130 mm (5-1/8")
Overall Arm length:  213 mm (8-3/8")
Tracking Error:  ±0,07°
Tracking Force Range:  0,5 - 2,5 grams
Cable Capacitance:  60 pf/meter; (87,5 pf total)
Usable Cartridge Weight (including Headshell):  10 - 19,5 grams
Supplied headshell:  7,2 grams
Turntable Section
Motor:  Linear BSL
Drive System:  Direct-drive
Control System:  Quartz lock control, magnedisc servo control system
Wow and Flutter:
WRMS :  0,025%
FG Direct :  0,015%
Signal-to-Noise Ratio:  78 dB (DIN-B)
Speed Accuracy:  better than 0,0003%
Start-up Time (at 33-1/3 rpm):  1/2 rotation
Platter Diameter:  320 mm (12-5/8 inches)
Platter Weight;  1,2 kg (with rubber mat)
Speeds:  33-1/3 and 45 rpm
Electromagnetic Breaking:  yes
Power Requirements:  AC 120 Volts , 60 Hz
Power Consumption: 23 Watts
Dimensions (W x H x D):  430 x 100 x 425 mm (17" x 4" x 16-3/4")
Weight:  7,4 kg (16 lb 5 oz)

Sony TC-K555ES cassette deck

Quite simply, Sony wanted to build a deck goodenough to be a part of the ES system. Se we addressed each of the three essential issues concerning cassette deck design - the heads, the transport, and the noise reduction system. Each was designed and constructed incorporting the most advanced technology available today.
A Third Head for Better Performance
Let's begin with the heads - the TC-K555ES employs a unique Independent Suspension three-head design. The record head has been designed with the wide head gap that is essential for wide dynamic range recordings, while the playback head retains the narrow gap required for accurate high frequency response. This is in sharp contrast to the glaring compromises of a two-head deck, in which a single head gap must adequately accommodate both requirements - an impossible task.

Superior Sound without the Struggle
Three-head design has been the cornerstone of superior cassette performance.  Unfortunately, in the past, three-haed decks have required critical and nearly constant azimuth adjustment to be effective. But Sony's inventive three-head design places the record and playback heads in close proximity to one another, eliminating the need for cumbersome azimuth adjustments. Yet the heads still remain physically distinct 9for optimized performance) and magnetically shielded from one another 9for minimal crossfeed). And Sony's exclusive independent Suspension design improves tape contact and azimuth accuracy, while reducing flux leakage. Result? Outstanding (and adjustment-free) performance.
The heads also combine an amorphous core material (whose irregular molecular structure provides superior magnetic performance) with modern laser construction technology to assemble the heads with exceptional precision. These laser Amorphous (LA) heads assure you superior sound and long life.

More Innovative Transport Technology
Another problem often associated with cassette decks is the distortion caused by inaccurate tape transport. A common manifestation of transport imperfection is called modulation noise. Sony's closed-loop dual capstan transport combats this problem. We've placed a capstan on either side of the tape path to isolate the tape passing across the heads form external influences 9such as the spooling motor). And, as a bonus, head-to-tape contact is also improved and performance remains consistent from one end of the tape to the other.

The Beautiful Sound of Silence
Perhaps the most heralded recent achievement in cassette deck technology is in the field of noise reduction - specifically, the development of Dolby C. and it's an impressive accomplishment, to be sure. With no more effort than simply flipping a switch, you can reduce the tape hiss in its most annoying frequencies by nearly 20 dB. The TC-K555ES lets you experience the wonder of Dolby C, while still providing compatibility with your tapes recorded with Dolby B - the older noise reduction system is included as well. And an anti-saturation circuit improves treble headroom by up to 4 dB, which makes proper recording utterly simple.
The TC-K555ES also includes a variety of convenience features, such as auto play; memory play; feaather-touch full-logic controls; a fluorescent Concentrated Display; variable bias for tape types I, II and II; and a Linear Counter that accurately reveals elapsed tape time in all transport modes (including rewind and fast forward). But it is most impressive for its unsurpassed basic performance and remarkable sonic capabilities.

Fastforward/Rewind Time:  80 sec C-60
Wow and Flutter (WRMS):  0,04%
Frequency Response (±3 dB, re-20 dB)
Metal Type IV  :  25 Hz - 18,000 Hz
FeCr  Type III :  25 Hz - 18,000 Hz
UCX Type II :  25 Hz - 17,000 Hz
AHF Type I :  25 Hz - 17,000 Hz
Signal-to-Noise Ratio (re 3% T.H.D., peak Wtd):
Dolby Nr Off
Metal Type IV  :  60 dB
FeCr  Type III :  62 dB
UCX Type II :  59 dB
AHF Type I :   56 dB
Dolby B NR On
Metal Type IV  :  67 dB
FeCr  Type III :  69 dB
UCX Type II :  66 dB
AHF Type I :   63 dB
Dolby C NR On
Metal Type IV  :  73 dB
FeCr  Type III :  75 dB
UCX Type II :  72 dB
AHF Type I :   69 dB
Total Harmonic Distortion (at 1 kHz, re 0 dB record level):  0,8% (Type IV, Type II)
Crosstalk (1 kHz):  60 dB between tracks
Separation (1 kHz):  35 dB between channels
Input Sensitivity
Line :  77,5 mV (50 k Ω) - 20 dB
Output Level
Line :  435 mV (10 k Ω) -5 dB
Headphone level (8 Ω):  -20 dB to - 50 dB
Power requirement:  AC 120 V, 60 Hz
Power Consumption:  26 watts
Dimensions (W x H x D):  430 x 105 x 285 mm (17' x 4-1/4" x 11-1/4")
Weight:  6,1 kg (13 lb 8 oz)

Marantz PM-7001 KI amplifier

PM7001 KI - Signature Integrated Amplifier
The KI Signature series is for many years synonym of finest electronics with best sound quality. Every aspect of the design and construction of the PM7001 KI stereo amplifier has received Ken Ishiwata's personal attention to attain uncompromised quality. The copper-plated chassis and rear panel reduce signal-degrading electromagnetic interference, while its rigid dual layer chassis and solid aluminum front panel virtually eliminate mechanical vibration. Delivering 2 x 70 watts into 8 ohms (120 watts, 4 ohm), this 2-stage constructed Current Feedback amplifier features symmetrical circuits for perfect image balancing, and uses audiophile Customized Components and the new HDAMs to preserve the music's dynamic structure, tonal quality and stereo image. Power handling characteristics have been reshaped and the large toroidal transformer is designed for this renewed circuitry. Its low impedance, wide-bandwidth power supply ensures a massive reserve of energy, to drive even difficult speakers with ease. Enjoy the exclusivity of the Ken Ishiwata Signature integrated amplifier.

Sufficient real power capability to fill the room with musical enjoyment
Ultra low vibration and leakage flux keeps the signal sharp and minimizes internal electro magnetic distortion
Excellent frequency response and superb sonic performance for the highest standard such as SACD
Achieving a unprecedented dynamic, accurate and detailed sound reproduction
Two times identically lay out symmetric audio circuit boards secure precise stereo imaging
Bypasses the tone control circuitry to ensure the purest sound quality
Allows tonal adjustment to personal taste
For bi-wired connection of loudspeakers, or for multiroom applications
Flexible system integration and total control via one system remote

A touch of Ken Ishiwata
The PM7001 KI is a clear example of benchmark engineering and craftsmanship of Ken Ishiwata and features a number of Marantz sound enhancements. The PM7001 KI integrated amplifier is built on a rigid dual layer enforced chassis. All of the analogue signal and control circuits are separated and shielded to prevent cross-talk and other unwanted interference. A high grade power supply centered around a special selected toroidal transformer secures maximum separation, clarity and dynamics. This design configuration is capable of a clear and powerful reproduction of the most demanding musical performances. The strength of each KI Signature design can be found in the attention to detail and the synergy of the different elements

Power Output (20 Hz - 20 kHz, simultaneous drive of both channels)
2 x 70 W at 8  load
2 x 100 W at 4  load
Total Harmonic Distortion (20 Hz - 20 kHz, simultaneous drive of both channels, 8 ):  0,02%
Power Bandwidth (8  load, 0,05% T.H.D.):  5 Hz - 60 kHz
Frequency Response:  5 Hz - 100 kHz ±3 dB
Damping Factor:  100 (8  load, 20 Hz - 20 kHz)
Input Sensitivity/Impedance
Phono  MM :  2,5 mV/47 k
Cd, Line, Tuner, Aux :  200 mV/20 k
Main In :  1,6 V/20 kohm
Output Load/Impedance
Pre Out :  16 V/560
Max. Allowed Phono Input :  130 mV
RIAA Deviation (20 Hz - 20 kHz):  ±0,5 dB
Signal-to-Noise Ratio (IHF-A, 1 W, 8  load)
Phono MM :  85 dB (5 mV input)
Cd, Line, Tuner, Aux :  88 dB (500 mV input)
Main IN :  107 dB
Tone Control
Bass :  ±10 dB at 50 Hz
Treble :  ±10 dB at 20 kHz
Power Requirement:  AC 230 V 50/60 Hz
Power Consumption:  470 W (2 x 100 W output, 4 )
Dimensions (W x H x D):  440 x 128 x 364 mm
Weight:  10,5 kg

Audio Analogue Puccini amplifier

 Stereo Integrated Amplifier
Power Output (both channels driven, 8 Ω):  2 x 40 W
Input Sensitivity/Impedance (RMS):
Phono MM :  10 mV /47 k Ω
Phono MC :  1 mV / 100 Ω
Line :  1 V / 50 k Ω
Signal-to-Noise Ratio
Phono MM :  better than 70 dB
Phono MC :  better than 60 dB
Line :  better than 80 dB
Phono MM :  better than 80 dB
Phono MC :  better than 70 dB
Line :  better than 90 dB
Tape Output Level/Impedance (RMS):  1 V / 600 Ω
Total Harmonic Distortion:  less than 0,196 % (at 40 W, 8 Ω, 1 kHz)
Damping Factor:  better than 100 (at 1 kHz, 8 Ω, 1 W)
Slew Rate:  better than 10/µsec
Bandwidth:  20 Hz - 20 kHz (±0,1 dB);  5 Hz - 20 kHz (+3 dB)
Channel Separation (at 1 kHz, unused input shorted):  better than 80 dB
Inputs:  Phono MM/MC, Tuner, CD, Video, Aux, Tape
Nominal Voltage Supply:  115 V AC, 230 V AC; 50/60 Hz
Max. Power Consumption:  170 VA
Dimensions (W x H x D):  445 x 85 x 365 mm (17,52" x 3,35" x 14,4")
Weight:  7 kg (15,5 lbs)

Harman/Kardon HK 725 pre-amplifier

Harman Kardon introduces low negatiwe feedback design for inaudible TIM distortion
For the last few years,, audio manufacturers have been rushing to bring you newer,lower T.H.D. levels in their amplifier sections. And every year, they've accomplished this the simplest way they could. By adding negative feedback, a form of electronic compensation. Unfortunately, this "cure" for T.H.D. - typically 60 - 80 dB of negative feedback - creates another form of distortion. Transient Intermodulation Distortion, or TIM, which does far more to degrade the music than T.H.D. at Harman Kardon, we lowered T.H.D. the right way. With unique circuit design (US Patent #4.176.323) that lets us use just a fracrtion of the negative feedback typically used. The result is our new HK 700 series High Technology Separates. Built around our low negative feedback amp/preamp combination that delivers a crystal clear, totally transparent 65 watts per channel. You can also choose from a full-featured digital tuner, a phase locked analog tuner, and the most advanced cassette deck on the market.

The HK 725 High Technology pre-amplifier
Many of the critics from the most widely recognized audiophile publications consider the HK 725 one of the best preamplifiers on the market
As with all our components, the KH 725 was designed with careful attention to even the finest details. Instead of the typical 4-stage phono section, we used 8 stages. And we used FET front ends on both our low and high level stages. These provide higher Signal-to-Noise ratio than other designs. Instead of conventional rotary tone controls, we used fixed resistor push-buttons because they provide lower distortion. The HK 725 also allows you to defeat the tone controls altogether, giving you the clearest, cleanest sound possible.
Even our volume controls is unique. With twelve wipers instead of the usual four. This extra bit of engineering not only provides a smoother acting, longer lasting control, but also helps lower distortion as well. And we didn't forget convenience. You get facilities for two tape decks, with 2 way tape copy that allows you to monitor any source you like while copying from one deck to another. Plus loudness, subsonic and high cut filters to help you contour your system to your listening environment.
The Harman kardon HK 725 stereo preamplifier is housed in a relatively small metal cabinet that matches its associated model HK 770 power amplifier. Individually, or in conjunction with the power amplifier, the sound quality is best described as "exceptionally clean" particularly with respect to the deep bass. An unusual feature is switch-selected bass and treble equalization, rather than rotary controls. The bass and treble have eight switches each, four providing boost in steps of 2 dB at 50 Hz and 10 kHz; four providing attenuation in 2 dB steps at the same frequencies. An illuminated switch in the center of each row of buttons provides a tone control defeat. Subsonic and high cut filters round out the equalization. Switching is provided for automatic tape duplication from, or to, either of two recorders. A panel-mounted headphone jack allows the signal to be monitored without going through the associated power amplifier. One unswitched and two switched AC convenience outlets are provided.
Frequency Response : less than 1 Hz to beyond 150 kHz   +0 -1 dB
Total Harmonic Distortion: 
Phono :  0,009%
High Level :  0,005%
Intermodulation Distortion:  0,009% at 2 volts output
RIAA Equalization:  ±2 dB (20 -20,000 Hz)
Signal-to-Noise Ratio:
Phono :  90 dB IHF-A
High Level :  106 dB IHF-A
Phono Overload:  250 mV at 1 kHz
Input Sensitivity/Impedance:
Phono :  2,3 mV/47 k Ω
High Level :  145 mV/23 k Ω
Slew Rate:  Greater than 200 volts/µsec to output with IHF standard
Tone Control Range
Low :  ±8 dB at 50 Hz
High :  ±8 dB at 10 kHz
Dimensions (W x H x D):  385 x 72 x 320 mm (15,2 x 2,9 x 12,6 inches)
Weight:  4,2 kg (9,25 pounds)

Harman/Kardon HK 770 power-amplifier

The HK 770 is certainly one of the most sophisticated stereo power amps you can buy. With 65 watts per channel, and plenty of extra headroom, the  HK 770 can easily handle the most demanding of transients.
Unlike most conventional amplifiers, negative feedback levels in the HK 770 are kept below 20 dB, reducing TIM distortion to inaudible levels. Also unlike conventional power amps, the brawn behind the Kh 770 comes from a pair of independent power supplies. We use two discrete rectifier circuits. Two sets of electrolytic capacitors. And two massive toroidal transformers, which eliminate the stray magnetic fields that cause hum.
Our twin power supply design provides you with two distinct benefits.
First, it eliminates the possibility of channel-to-channel interference. It also prevents one channel from draining the power available to the other. Each power supply is further divided into high and low level stages. This ensures that the power requirements of the high level stages do not drain current at the expense of the low level stages
Unlike most power amps, the HK 770 gives you, accommodations for two pairs of speakers with independent speaker switching. Plus a power display that allows you to monitor performance. And for more accuraate power readings at low listening levels, display aensitivity can be increased by a factor of 10. The HK 770 packs a lot of power and lot of technology into a surprisingly compact amplifier.
The Harman Kardon HK770 Stereo Power Amplifier is FTC rated for 8 ohms at 65 watts RMS per channel, 20 Hz to 20 kHz, at less than 0,03% Total Harmonic Distortion. Test results were considerably better than even the low claimed distortion, resulting in some of the lowest distortion figures ever attained from a power amplifier. The sound quality reflects the low distortion, being exceptionally clean, particularly in the deep bass. Special construction techniques result in an unusually small cabinet for an amplifier of this power rating. The front panel has left and right LED dual range output power indicators calibrated 0,05-100 watts and 0,005-10 watts into 8 ohms.
The LED power output indications were essentially precise, with a virtually flat 20 Hz to 20 kHz Frequency Response. An output power hold-off prevents power supply turn-on transients from being fed to the speakers. One unswitched AC convenience outlet is provided.
Power Output:  65 watts (RMS per channel into 8 Ω, both channels driven simultaneously from 20 Hz to 20 kHz with less than 0,03% T.H.D.)
Power Bandwidth:  less than 8 Hz to 100 kHz at 32,5 watts per channel with less than 0,03% T.H.D.
Total Harmonic Distortion:  0,006% at rated output
Intermodulation Distortion:  less than 0,01% at rated output, both channels driven at different operating frequencies
Frequency Response:  below 1 Hz to 250 kHz +0, -3 dB
Damping Factor:  greater than 50
Slew Rate:  150 V/µsec into 8 Ω at rated power output, both channels driven
Square Wave Rise Time (20 kHz):  1,5 µsec into 8 Ω at rated power output, both channels driven
Square Wave Tilt:  less than 2% at 20 Hz
Total TIM Distortion:  less than 0,007% at rated output
Total Interface I.M. Distortion:  less than 0,007%
Power Supply Crosstalk:  greater than 100 dB (20 Hz to 20 kHz) unused channel sherted input
Amplifier Configuration:  Twin toroidal transformers with positive and negative supplies plus high and low voltage supplies for output and driver stages
Signal-to-Noise Ratio:  123 dB (IHF-A)
Input Impedance:  35 k Ω
Sensitivity:  1,2 V for rated output
Dimensions (W x H x D):  385 x 72 x 320 mm (15,2" x 2,9" x 12,6")
Weight:  10,1 kg (22,2 lbs)