Fisher MT-6225 turntable

A Major Technological Advance in Turntable Engineering MT6225

 

The worlds first linear motor direct drive turntable

 

One of the problems in improving turntable performance, especially with direct drive systems, is the difficulry of reducing woa and flutter due to cogging action of the direct drive motor.

With its limited number of poles (usually 12) , a conventional direct drive system has an inherent problem, at its relatively slow operating speed, of low starting torque.

To solve these problems and improve turntable performance, Fisher has engineered the linear motor, 120 pole direct drive systems.

 

The Platter is The Motor

In effect, the platter becomes the motor of the MT6225. and Fisher's 120 pole design practically eliminates cogging action and wow and flutter - to a totally inaudible 0,03%

And the linear motor direct drive system further reduces turntable rumble to an extremely low -70 dB, so far below hearing level to be completely inaudible.

 

How it works

A continuous ring of magnetic material, containing, 120 magnetic poles, is attached to the inside bottom rim of the platter. As the platter rotates, each pole opposes one of the electromagnetic drivers on the base top. Each of the 120 poles is attracted or repelled  as it passes the driving electromagnets for smooth, stable operation.

An electronic sensing device monitors the platter's speed, and acts as a servo feedback control to maintain practically perfect speed accuracy. A built-in strobe and pitch controls are provided.

The speed accuracy of the system is independent of line voltage fluctuations.

 

The Arm

The handsomely styled Fisher MT6225 is equipped with a professional type horizontal and vertical gimbal suspended tone arm for performance commensurate with its technologically advanced design.

The arm accepts all standard cartridges. The auto-return system which returns the arm to rest at the end of a record is also an advanced design with no restraints on its lateral or vertical motion during operation.

The arm has adjustable tracking force with calibrated settings from 0,6 to 3,5 grams. There's also precise variable anti-skate, and viscous damped cueing. The MT6225 also has an aluminum alloy die cast platter, and a walnut grain vinyl veneer wood base.

 

Specifications

Motor:  Linear Direct

Drive:  Direct drive

Wow and Flutter:  0,03% (WRMS)

Rumble:  -70 dB

Speed Variation:  ±0,5%

Speed Control Range:  ±3%

Tracking Force Range:  0,6 - 3,5 grams

Platter:  Die cast aluminum

Platter Diameter:  12-15/16"

Platter Weight:  2,2 lbs

Record Speed Selector:  33-⅓ and 45 rpm

Tone-arm:  S-shape form

Resonance:  less than 10 Hz

Effective Length:  222 mm

Bearing Type

Horizontal :  Thrust

Friction Sensitivity :  0,15 gram

Vertical :  Pivot

Friction Sensitivity :  0,2 gram

Max. Tracking Error:  ±1,5°

Anti-skate:  adjustable control

Cueing:  Viscous damped

Power Requirements:  110V - 220 V Ac 50/60 Hz

Dimensions (W x H x D):  17-3/4" x 6" x 14-1/4"

Weight:  17,7 lbs

Canton GLE 45 loudspeakers

GLE series loudspeakers from Canton

Canton's new GLE loudspeakers represent a level of performance in respect to size that is, as far as is known, unequaled by any other designs.

The technical advances and creative thought behind their development is apparent the moment you hear them. Indeed, their unexampled realism and innate musicality could only be exceeded by the original performance.

The series is composed of six models - three 2-way systems GLE 40, GLE 40F, GLE 45  and three 3-way units, GLE 50, GLE 60 and GLE 70. all six bear an unmistakable family resemblance, not only in appearance, but in sound quality as well.

Among their more notable characteristics and features are high power handling capacity, extended high frequency response (up to 30,000 Hz), new pressure cast aluminum woofer frames and removable metal grilles.

In addition, the GLE series loudspeakers all make use of a new concept in the design of frequency dividing networks that insures equeal energy response across the entire audio spectrum, as well as a seamless transition from driver to driver.

All models are available in genuine walnut veneer, matte white and matte black finishes.

 

Specifications 

Frequency Response:  38 - 30,000 Hz

Impedance:  4 Ω  nominal

Minimum Recommended Amp. Power:  7,5 watts

Power Handling: 

45 watts continuous

70 watts peak

Crossover Frequency:  1700 Hz

Crossover Slope:  10 - 12 dB/octave

Driver Complement:

Low Frequency :  200 mm (7,9") woofer

High Frequency :  19 mm (0,75") dome tweeter

Room Listening Volume:  1,9 watts (required amplifier output for 80 dB at 3 m distance)

Cabinet Resonance:  800 Hz

Distortion (above 300 Hz at 86 dB):  les than 1,0%

Angle of Dispersion:  more than 125°

Connectors:  Push-button

Dimensions (W x H x D):  320 x 220 x 180 mm (12,8" x 8,8" x 7,2")

Weight:  6,4 kg (11,88 lbs)

Canton GLE 40 loudspeakers

GLE series loudspeakers from Canton - model GLE 40

 

Specifications GLE 40

Frequency Response:  42 - 30,000 Hz

Impedance:  4 Ω  nominal

Minimum Recommended Amp. Power:  9 watts

Power Handling: 

40 watts continuous

60 watts peak

Crossover Frequency:  1400 Hz

Crossover Slope:  8 - 23 dB/octave

Driver Complement:

Low Frequency :  160 mm (6,3") woofer

High Frequency :  19 mm (,75") dome tweeter

Room Listening Volume:  2,25 watts (required amplifier output for 80 dB at 3 m distance)

Cabinet Resonance:  90 Hz

Distortion (above 300 Hz at 86 dB):  les than 1,5%

Angle of Dispersion:  more than 125°

Connectors:  Push-button

Dimensions (W x H x D):  265 x 180 x 150 mm (10,6" x 7,2" x 6")

Weight:  3,35 kg (7,37 lbs)

 

Canton GLE 40F loudspeakers

 

GLE series loudspeakers from Canton - model 40F

 

Specifications GLE 40F

Frequency Response:  48 - 30,000 Hz

Impedance:  4 Ω  nominal

Minimum Recommended Amp. Power:  9 watts

Power Handling: 

40 watts continuous

60 watts peak

Crossover Frequency:  1700 Hz

Crossover Slope:  8 - 23 dB/octave

Driver Complement:

Low Frequency :  160 mm (6,3") woofer

High Frequency :  19 mm (,75") dome tweeter

Room Listening Volume:  2,25 watts (required amplifier output for 80 dB at 3 m distance)

Cabinet Resonance:  120 Hz

Distortion (above 300 Hz at 86 dB):  les than 1,5%

Angle of Dispersion:  more than 125°

Connectors:  Push-button

Dimensions (W x H x D):  320 x 200 x 80 mm (12,8" x 6,8" x 3,2")

Weight:  3,1 kg (6,82 lbs)

Dual 1249 turntable

Single-play / multi-play , belt-drive turntable with fully automatic start and stop, plus continuous play. 

Mode selector paralleles tonearm to record in single-play for accurate vertical tracking.

True, four-point gimbal centers and pivots the tonearm mass at intersection of horizontal and vertical axes. Tonearm is dynamical balanced in all planes. The four needle-point pivot are first hardened, then honed, a process which produces microscopically smooth surfaces. The prcision ball-bearing races are only 0,157 inch diameter.

Unique "Vario-pulley" used in Dual three belt-drive models is precision-machined for perfect concentricity and balance. Speeds are adjust by expansion and contraction of pulley circumference, belt is never twisted or distorted.

 

For several years, independent surveys of component owners - audio experts, hifi editors, record reviewers, readers of the music/equipment magazines - have shown that more of them own Duals than any other turntable. This is quite a testimonial to Dual's quality performance, reliability and fully automatic convenience.

We believw the new 1249 will add even more serious music lovers to the roster of Dual owners, as it provides every feature, innovation and refinement long associated with Dual turntables plus some new ones. And all in a newly designed chassis that complements the superb design and meticulous engineering of the 1249.

The low-mass tubular tonearm pivots in a true four-point gyroscopic gimbal suspended within a rigid frame. All tonearm setting are easily made to the exacting requirements of the finest cartridges. The tonearm is vernier adjustable for precise balance, tracking pressure is calibrated in tenths of a gram; anti-skating is separately calibrated for conical, elliptical and CD-4 styli. Tracking is flawless at pressures as low as a quarter of a gram. In single play, the tonearm parallels the record to provide perfect vertical tracking. In multi-play, the Mode Selector lifts the entire tonearm to parallel the center of the stack. All operations are completely flexible and convenient - and they are foolproof. The tonearm can be set on the record manually or by using the viscous- damped cue-control or by simply pressing the automatic switch. You also have the options of single-play, continuou-repeat, or multiple-play. The dynamically-balanced cast platter and flywheel are driven by an 8-pole synchornous motor via a precision-ground belt. Pitch is variable over a 6% range and can be conveniently set to exact speed by means of an illuminated strobe, read directly off the rim of the platter.

 

 

Specifications

Drive:  Dual 8-pole synchornous motor; flat belt for flywheel drive

Starting Time:  approx. 2 sec. (33-⅓rpm)

Platter:  Non-Magnetic, dynamically balanced

Diameter :  305 mm

Weight :  1,3 kg ( platter with flywheel drive 2,1 kg)

Platter Speeds:  33-⅓ and 45 rpm. Automatic tonearm set-down coupled with speed adjustment

Pitch Control Variation:  Adjustment range of approx. 1semitone (approx 6%) at both platter speeds

Speed Control:  with illuminated stroboscope for platter speeds (33-⅓, 45 rpm)

Illuminated Strobe Sensitivity for Speed Deviation of 0,1% :

3,0 bars/min at 50 cps

3,6 bar/minn at 60 cps

Wow and Flutter:  According to DIN 45 507 (GIS < ±0,08%

Rumble (according to DIN 45 500):

Unweighted :  better than 42 dB

Weighted :  better than 63 dB

Tonearm:  torsion-resistant tubular aluminnum tonearm in four-point gimbal

Effective Length:  222 mm

Offset Angle:  25° 20'

Tangential Tracking Error:  0,16 °/cm

Tonearm Bearing Friction (related to stylus tip):

Vertical :  less than 0,07 mN (0,007 p)

Horizontal :  less than 0,16 mN (0,16 p)

Stylus Pressure:  0 - 30 mN (0 - 3 g) Infinitely variable with 1 mN (1/10 g), calibration from 0 - 15 mN (0 - 1,5 g) operable from 2,5 mN (0,25 g) stylus pressure up

Cartridge Holder:  Removable, accepting any cartridges with 1/2", mounting and weight from 4,5 to 10 g

Adjustable Overhang: 5 mm

Current:  AC 50 or 60 Hz, changeable by changing motor pulley

Line Voltage:  110 - 130 V 0r 220 - 240 V , switchable

Power Consumption:  approx. 10 Watts

Dimensions (W x H x D):  420 x 148 x 365 mm

Weight:  7,6 kg

Akai X-1800SD reel/cartridge recorder

Akai Cross-Field Reel-to-reel and Cartrdidge Stereo 8 Recorder

Your dream of cartridge recording and playback or Reel-to-Reel recording and playback with the same recorder has come true. This is possible with Akai's X-1800SD, a novelty in the tape recorder world. Akai has combined in one tape recorder all the features that could beattained by using three conventional interconnected recorders.

Cartridge 8-track stereo recording and playback, with an one micron gap head;  Reel-to-Reel 4-track Stereo/Monaural recording and playback, with the Cross-Field head of superior recording capacity; and transfer from rell to cartrdige are unique and exclusive features of this model.

 

Outstanding Features

Reel-to-Reel

4-track stereo/monaural recording and playback

Tape speeds; 1-7/8; 3-3/4 and 7-1/2 ips (15 ips with 15ips adaptor kit)

Heads; Cross-Field head system (Erase, Recording/Playback and Nias heads)

Wide Cross-Field Frequency Response

Two lever system ensures dependable and durable operation

Track selector for simple selection between stereo and monaural

Automatic shut-off and Instant Stopcontrol

3-digit index counter with reset button

Tape cleaner with release button

Tape lifter in fast forward and rewind operation

Cartridge

8-track stereo recording and playback

Transfer fom reel to Cartridge

Transfer safety lock

Tape speed 3-3/4 ips

Heads, Erase and one micron gap recording/playback heads

Cartridge program selector button

Program selection may be remote controlled

Program indicator lamp (also indicates whether cartridge is perfectly set)

One hour of continuous stereo recording and playback

300 foot cartridge tape

Cartridge automatic stop

Reel-to-Reel/Cartridge

Hi-fi stereo sound produced by high capacity 12 W solid stste amplifier and high compliance self-contained speakers

Silicon transistors and shield type head for high Signal-to-Noise ratio

Strudy mechanism for absolute duraability

Main amplifier protector fuse

Tone controls

Tape speed equalizer high visable twin type VU meter

Speaker On/off switch

DIN jack, Stereo headphone jack

Fine oil-finished wooden cabinet

Vertical and horizontal operation

Universal voltage selector (100 V - 240 V , 50/60 Hz)

 

Cross-Field Head

On conventional recorders the signal and biass are applied to the same recording head. Therefore the frequencies recorded, especially the high frequency component of the recorded signal tend to be attenuated or erased by the effect of this bias field. On the exclusive Akai Cross-Filed head which was developed by Akai for practical use the signal and bias heads are mounted in opposition with their centres slightly off. As the recorded signal is entirely unaffacted by the prevailing effect of the bias fielf, the tape can be recorded over the entire frequency spectrum with maximum fidelity.

 

One Micron Gap head

Model X-1800SD utilizes the cross-field head to obtain an amazing level of recording characteristics in reel-to-reel recording. In cartridge recording, the high-quality one micron gap head designed by Akai also gives excellent recording characteristics. This recording characteristic, 50 to 17,000 Hz ±3 dB at a tape speed of 3-3/4 ips, produces excellent results for cartridge tape recordings.

 

8-track stereo recording/playback (cartridge)

Model X-1800SD employs the 8 track stereo system on the cartridge. The tape has a total of eight tracks, two of which are used at a time for stereo recording or playback. These are four choices of channels for stereo recording and playback. When the tape ends, the next channel is automatically positioned for recording or playback. Recording or playback time for one channel is fifteen minutes, and continous one hour on four channels by using 300 foot cartridge tape. The desired channel may be easily selected by manually pushing the Cartridge program Selector Button.

 

Cartridge recording tape (ACT-200, ACT-300)

Akai's 1800 series tape recorders, Model 1800L and X-1800SD are the latest models that are capable of recording with a cartridge tape. For use in this type of recording, we have cartridge recording tapes, ACT-200 with 200 foot long tape, and ACT-300 with 300 foot long tape. This cartridge tapes are highly recommended for best results.

 

Specifications

Reel Tape Spped:  1-7/8, 3-3/4, 7-1/2 ips

Cartridge Tape Speed:  3-3/4 ips

Wow and Flutter::

Reel

7-1/2 :  less than 0,12% RMS

3-3/4 :  less than 0,15% RMS

1-7/8 :  less than 0,20% RMS

Cartridge:  less than 0,25% RMS

Frequency Response

Reel

7-1/2 :  30 - 23,000 Hz ±3 dB

3-3/4 :  30 - 18,000 Hz ±3 dB

1-7/8 :  30 - 9,000 Hz ±3 dB

Cartridge :  50 - 17,000 Hz ±3 dB

Signal-to-Noise Ratio

Reel :  better than 50 dB

Cartridge :  better than 45 dB

Input Level

Mic ;  better than 0,5 mV

Line :  better than 60 mV

Power Output:  6 W maximum each channel at Music Power,total 12 W

Equalization:  Correct equalization for plaback of tapes recorded to the NARTB curve

Recording level Indicator: Twin type VU meter

Recording System:

Reel :  4-track stereo/monaural, Cross-Field bias system

Cartridge :  8-track stereo system

Fast Forward and Rewind Time

Reel :  150 seconds using 1200 foot tape at 50 Hz or 120 seconds at 60 Hz

Recording Capacity

Reel : 

8 hours monauraal recording at 1-7/8 ips (1200 foot tape)

4 hours stereo recording at 1-7/8 ips

Cartridge :  one hour stereo recording at 300 foot cartridge tape

Maximum Reel Size:  7-inch

Motor:  2-speed induction motor

Speakers:  2 x 4" speakers

Semiconductors:  19 Transistors, 13 Diodes

Power Supply:  AC 100 - 240 V,, 50/60 Hz

Power Consumption:  60 VA

Dimensions:  378 x 338 x 238 mm (16" x 13-1/2" x 9-1/2")

Weight:  17 kg (37,4 lbs)

Thorens TSP-100 loudspeakers

 

High-end floor-standing loudspeakers.

Two-way with bass-reflex front design.

Die-cast frames with Kevlar membranes.

Separate pedestal featuring adjustable spikes.

Selected genuine veneers available in the following finishes; 

Black ash, natural cherrywood, natural beechwood. 

Special stains on oak veneers on request.

 

Specifications

Impedance:  4 - 8 Ω

Sensitivity:  92 dB

Frequency Range:  40 - 20,000 Hz

Power Limits:

120 W average

160 W max

Drive Units:

High Frequency :  1 x 25 mm dome tweeter

Mid/Low Frequency :  2 x 170 mm Kevlar cone woofer

Dimensions (W x H x D):  205 x 980 x 295 mm

Pedestal :  245 x 19 x 330 mm

Weight:  21,0 kg

Thorens TSP-80 loudspeakers

 

High-end floor-standing loudspeakers.

Two-way with bass-reflex design.

Die-cast frames with Kevlar membranes.

Separate pedestal featuring adjustable spikes.

Excellent veneers available in the following finishes;

Black ash, natural cherrywood, natural beechwood

Special stains on oak veneers on request.

 

Specifications

Impedance:  4 - 8 Ω

Sensitivity:  91 dB

Frequency Range:  50 - 20,000 Hz

Power Limits:

100 W average

150 W max

Drive Units:

High Frequency :  1 x 19 mm dome tweeter

Mid/Low Frequency :  2 x 130 mm Kevlar cone woofer

Dimensions (W x H x D):  175 x 850 x 265 mm

Pedestal :  205 x 19 x 290 mm

Weight:  14,5 kg

Sony SSU-1000/1200 loudspeakers

Two-way speaker systems

Features

2-way, direct radiating acoustic suspension design

Exceptionally smooth, flat frequency response in a 2-way design

High power handling capability and excellent bass response for smaal size enclosures

Minimum system distortion and coloration, for clear, well defined sound

Powerful, heavy magnets providing increased efficiency

Scratch resistant walnut grain vinyl enclosures, designed for vertical or horizontal placement

Attractive, removable flat cloth grilles, selected for maximum acoustic transparency

 

Sony's acoustic suspension speaker systems offer exceptionally weill defined sound, with bass response not likely to be found in other 2-way systems. In accord with Sony engineering standards which demand the lowest possible levels of system distortion and coloration, the speakers fulfill strict specification requirements. Listeners will be impressed with the sound which results, especially when they compare the Sony speakers with systems of similar design and capacity.

Feature and performance Highlights

The Sony 2-way acoustic suspension speaker systems have cone drivers, placed in extra thick particle board enclosures which are fully sealed, and lined with fiber glass. This construction avoids air leakage which would cause deterioration in bass response and allows a high power handling capability (50 W RMS, weighted pink noise continuous). Thus good response is assured, with a constant sound pressure level, minimum noise and distortion and good damping.

The two cone tweeters are also sealed tightly, creating a constant sound pressure level which precludes interference from the woofers and assures an ideal foll-off of low frequencies. In addition, the outside edge of the cones are treated with speciaal damping material, smoothing out frequency response even further and limiting coloration.

Equal care has been given to exterior design. Housed in hand-some walnut grain vinyl enclosures, with complementary flat cloth grilles, the speakers will look as great as they sound in every listening room.

 

Specifications

SSU-1000

Nominal Impedance:  8 Ω

Frequency Response:  50 Hz - 18,000hz

Crossover Frequency:  1500 Hz 96 dB/oct)

Max. Handling Power:  50 watts (RMS, weighted pink noise continous)

Minimum Power Requirement:  15 W (continous RMS)

Speaker Complements:

LF : 1 x 8" cone woofer

HF : 1 x 3" cone tweeter

Dimensions (H x W x D):  17-11/16" x 11-11/16" x 8-1/4"

Weight:  17 lbs

 

SSU-1200

Nominal Impedance:  8 Ω

Frequency Response:  45 Hz - 18,000hz

Crossover Frequency:  1000 Hz 96 dB/oct)

Max. Handling Power:  50 watts (RMS, weighted pink noise continous)

Minimum Power Requirement:  15 W (continous RMS)

Speaker Complements:

LF : 1 x 10" cone woofer

HF : 1 x 3" cone tweeter

Tweeter Control:  2 position, 0; +3 dB

Dimensions (H x W x D):  23-1/8" x 13-1/8" x 10"

Weight:  29lbs

Sony STR-7015 receiver

FM Stereo - FM/AM receiver

Features:

True complimentary direct coupled power output stage with differential dual power supply

FM IF stage with IC and solid-state filter

Triple tuned soild- state AM IF stage

 

Budget minded hi-fi enthusiasts will find the STR-7015 well within their reach and well up to hi-fi standards. Power output is moderate but adequate to drive a fairly efficient speaker. It doesn't take much to really appreciate the STR-7015's circuitry and performance features. Another fine example of Sony's advanced engineering and component design expertise.

 

Tuning

Up in the front-end the STR-7015 features in the FM stage an IC and soild-state IF filter for high stability and smooth, clean listening. Phase locked Loop (PLL) circuitry in the FM stereo demodulator delivers high stereo sepaaration and low distortion performance. Triple-tuned soild-state AM IF stage offers high selectivity for great AM listening. An illuminated frequency linear FM dial scale and signal strength meter make tuning a snap. FM interstation muting quiets the annoying between station noises for noise-free tuning.

Preamplifier and Control ections

A front panel Mic input jack allows for voice mixing with any source, i.e., phono, tuner, etc. PA applications are also possibile in addition to voice mixing for recording. Loudness compensation offers precise bass response and overall tonal quality at low listening levels. An attractive gold anodized control panel includes a headphone jack, mode switch, bass and treble controls and a tape monitor.

Power Amplifier Section

The STR-7015 features a direct coupled true complimentary power output stage that delivers 15 watts per channel, minimum RMS at 8 ohms from 40 Hz to 20 kHz with no more than 0,8% Total Harmonic Distortion. Though the power output is modest, the performance is outstanding. For operation of main and remote speaker, the STR-7015 features two pairs of speaker outputs in addition to a speaker selector switch.

 

Specifications

Amplifier Section

Continuous Power Output (RMS):  15 watts per channel minimum RMS at 8 Ω from 40-20,000 Hz with no more than 0,8% T.H.D.

IM Distortion:  0,8% at rated output and 1,0% at 1 W output

Damping Factor:  25 at 8 Ω, 1 kHz

Input Sensitivity/Impedance

Phono :  2,5 mV/47 k Ω

Microphone :  2 mV/47 k Ω

Aux :  250 mV/100 k Ω

Tape ;  250 mV/100 k Ω

Rec/Pb :  250 mV/100 k Ω

Output Voltage/Impedance

Rec Out :  250 mV/10 k Ω

Rec/Pb:  30 mV/82 k Ω

Frequency Response:

Phono :  RIAA ±2 dB

Microphone :  30 Hz - 10 kHz +0 -3 dB

Aux, Tape, Rec/Pb :  30 Hz -40 k ohz +0 -3 dB

Signal-to-Noise Ratio: 

Phono :  60 dB

Microphone :  60 dB

Aux ;  70 dB

Tape : 80 dB

Rec/Pb Input :  80 db

FM Tuner Section

Sensitivity:  2,2 µV

Signal-to-Noise Ratio:  68 dB

Capture Ratio:  3,0 dB

Selectivity:  60 dB

Total Harmonic Distortion

Mono :  0,3% at 400 Hz , 100% modulation

Stereo ; 0,8% at 400 Hz 100% modulation

FM Stereo Separation:  better than 35 dB at 400 Hz

Frequency Response:  30 Hz to 15,000 Hz +0 -2 dB

AM Tuner section

Total Harmonic Distortion:  0,8%

Signal-to-Noise Ratio:  50 dB

General Section

Power Requirements:   AC 120 V, 60 Hz

Power Consumption:  85 W

Dimensions (W x H x D):  16-3/8" x 5-7/8" x 13-3/8"

Weight:  16 lbs 5 oz

McIntosh MC 2100 power amp

 

The Solid State Stereo Power Amplifier

A two stage preamplifier with three transistors in each channel increases the input voltage 16 dB .

There are 13 transistors in each power amplifier section. The two stage preamplifier is fed to a pair of matched transistors arranged as an emitter coupled amplifier with two inputs and one output. The signal from the preamplifier section connects to one of these inputs. Both AC and DC negative feedback are applied to the other input. This large quantity of feedback is used to reduce noise and distortion. The signal is then fed to a voltage amplifier. The voltage amplifier is followed by two driver transistors.

The output section is arranged as a series push-pull amplifier. The power transistors used in the output section of your MC 2100 are selected for their high power dissipation capability, wide frequency response, and large "safe operating area." In addition, each power transistor is given four separate tests before it is put in your MC 2100. This additional testing makes sure your MC 2100 will deliver its rated power from 20 Hz to 20 kHz with low distortion and complete reliability. 

The power transistors are mounted on oversized anodized heat sinks. The heat sinks assure that under normal operation the transistors will operate at a low temperature. If temperatures increase due to a shorted speaker, or restricted ventilation, an automatic temperature sensing device turns off the MC 2100. The device operates automatically at a preset temperature. The MC 2100 will turn on again when the temperature has returned to normal limits. This additional feature gives your MC 2100 complete reliability under the most extreme operating conditions.

The output stages are matched to the load by the Mclntosh autoformer. The Mclntosh autoformer is carefully wound using Mclntosh trifilar winding and interleaving techniques. Trifilar winding and interleaving gives the autoformers exceptional bandwidth. The autoformers properly match the power transistors to 4, 8, and 16 ohms loads at all audio frequencies.

The use of the Mclntosh designed trifilar autoformer makes the Mclntosh solid state amplifiers the only amplifiers that deliver Full Power at All Speaker Impedances. You have not been power penalized for your choice of loudspeakers when using the Mclntosh MC 2100.

 Another of the advantages of the autoformers is the 25 volt output for a constant voltage distribution system. With the MC 2100 several sets of speakers can be operated independently throughout your home.

To further insure reliability a special power output Sentry Monitoring Circuit prevents failure of the power output transistors due to excessive mismatch of the output. When your MC 2100 operates normally the Sentry Monitoring Circuit has no effect on signals passing through the power amplifier. If the power dissipation should rise above normal operation, the Sentry Monitoring Circuit restricts the drive to the output transistors. The Sentry Monitoring Circuit acts instantaneously for any input signal or load combination. This arrangement assures complete circuit reliability. Only Mclntosh gives you this degree of protection.

There are three separate power supply sections. One positive and one negative high current supply is used for the output stages. The other positive supply is used for the driving amplifier stages. All supplies are full wave and use silicon rectifiers. Adequate filtering is used to assure an absolute minimum of hum. The power output stage filter capacitors have very high capacity, which allows full power output below 20 Hz. The power transformer is generous in size and runs cool, even under heavy use.

 

Specifications

Power Output

Stereo :  105 watts (continuous, per channel, both channels operating, which is):

20.5 volts RMS across 4 Ω 

29.0 volts RMS across 8 Ω 

41.0 volts RMS across 16 Ω 

Mono :  210 watts (continuous, which is):

20.5 volts RMS across 2 Ω 

29.0 volts RMS across 4 Ω 

41.0 volts RMS across 8 Ω 

Harmonic Distortion

Stereo :  Will not exceed 0.25% at any power level to 105 watts output per channel from 20 Hz to 20,000 Hz both channels operating. Typical performance is less than 0.1% at rated power. Distortion decreases as output power is reduced

Mono :  Will not exceed 0.25% at any power level to 210 watts output from 20 Hz to 20,000 Hz. Typical performance is less than 0.1% at rated power. Distortion decreases as output power is reduced

Intermodulation Distortion

Stereo :  Will not exceed 0.25% if instantaneous peak power is 210 watts or less per channel with both channels operating for any combination of frequencies 20 Hz to 20,000 Hz

Mono :  Will not exceed 0.25% if instantaneous peak power is 420 watts or less for any combination of frequencies 20 Hz to 20,000 Hz

Frequency Response:

20 Hz to 20,000 Hz (+0 -0,25 dB) at rated power

15 Hz to 60,000 Hz (+0 -0,5 dB) at rated power

10 Hz to 100,000 Hz (+0 -3,0 dB) at one-half rated power

Noise and Hum:  90 dB or more below rated output

Output Impedance

Stereo :   4, 8, and 16 Ω 

Mono :  2, 4, and 8 Ω 

Output Voltages: 25 volts (stereo and mono)

Damping Factor:

20 at 4 Ω  output

14 at 8 Ω  output

11 at 16 Ω  output

Input Sensitivity:  0.5 volt. (Level control provided for higher input voltage)

Input Impedance: 200,000 Ω 

Power Requirements: 

120 volts 50/60 Hz, (50 watts at zero signal output)

450 watts at rated output

Semiconductors:  32 silicon transistors;  14 silicon rectifiers and diodes

Dimensions (W x H x D): 298,5 x 196,9 x 431,8 mm  (11" x 7" x 17")

Chassis:  Chrome and black.

Weight:  25,86 kg (57 pounds) 

 

Special Features: 

The amplifier is completely stable when connected to any loudspeaker system or even to any reactive loads. The MC 2100 has special circuits to prevent damage by short circuit or open circuit of the output loads, or by any amount of output impedance mismatch. Thermal cutouts are mounted on the output transistor heat sinks to provide protection in the event of inadequate ventilation.

Performance Limits are the maximum deviation from perfection permitted for a Mclntosh instrument. We promise you that the MC 2100 you buy must be capable of performance at or exceeding these limits or you get your money back. Mclntosh is the only manufacturer that makes this guarantee. 

Akai GX-F90 cassette deck

Stereo Cassette Tape Deck

Super Slim Up to The Minute Design with Feather Touch Control

 

Super GX Heads Usher in The Age of Metal Tape

Superficial modifications would have been totally inadequate to bring about the greatly improved performance achieved in the GX-F90. for this, Akai's engineers went to the heart of the matter - the heads. The Super GX Head follows in the tradition of the immensely successful GX and new GX heads. It employs improved crystal ferrite as the core material, a super-hard substance which provides longer head and tape life. The heads of the 3-head system maintain optimum individual gap widths for better recording and playback characteristics with virtually no azimuth loss. Another advantage is that it enables direct tape monitoring. All this makes the Super GX Head ideal for metal tapes, with their greater dynamic range and improved Signal-to-Noise Ratio. Greater performance is obtained from conventional tapes, too.

 

Two-Motor System for maximum Stability.

High torque and minimal ripple, resulting in Wow and Flutter of less than 0,08 (DIN) are the major advantages of the GX-F90's transport mechanism. The Direct Capstan Drive system employs a coreless/FG Servo DC motor incorporating a Sample-and-Hold circuit for the capstan and a coreless DC servo-controlled motor for the reel drive.

 

FL Display BAR Meters

Reflecting the latest trend in electronics, the conventional needle-type level meter has been replaced in the GX-F90 by a 48-segment fluorescent meter. Using 2 colours to indicate levels below and above 0 dB, it shows either the peak level or VU reading at the press of a button. The advanced digital circuitry provides level readings of much higher accuracy than the mechanical type.

 

Playback - It's All Automatic

Let the instant Programme Locating System find the song you want to play. The system detects the beginning of the song by the volume level and the time constant and then commences playback automatically. The song can also be played repeatedly by setting the index counter to "000" and pressing the Repeat and Memory buttons. For continuous playback, press the Repeat button and at the end of the tape it will rewind to the beginning and resume playback.

 

Illuminated IC Logic Control Buttons

The feather-touch logic controls light up when touched. And with the Pause button on, when you press a mode button, the button will flash, to indicate the next mode. What's more, you can switch directly from one mode to another without having to press the Stop button. Operating the deck is thus exceptionally fast and simple

 

Calibration Tone Switch and Adjusters

A Cal Tone button is provided which activates a built-in oscillator to supply a 400 Hz recording signal for recording calibration adjustment. Use this reference signal when performing re-calibration with the two Rec Cal adjusters to match the characteristics of the tape being used. An especially useful feature when making Dolby NR recordings.

 

Dolby NR System and MPX Filter

Much has been written about the unique Dolby NR system, and how it greatly improves the sound of cassette tapes. It is exemplified by the GX-F90's Dolby NR system which works by raising low level signals prior to recording and then lowering them proportionately on playback. This results in sharply reduced tape hiss and an improved Signal-to-Noise Ratio of up to 10 dB above 5 kHz. The Dolby effect can be monitored during recording to cut the disturbance caused by the 19 kHz pilot signal during FM stereo broadcast recording with Dolby NR system, this deck ha an MPX Filter Switch. The ability to turn off the filter at all other times ensures full wide range frequency response.

 

The Akai A.D.R. System

This system designed by Akai automatically adjusts recording equalization at high frequencies while at the same time suppressing intermodulation distortion Sound that is crystal clear over the entire frequency band is obtained.

 

Specifications

Track System:  4-track, 2-channel stereo system

Tape:  Compact Cassette type

Tape Speed:  4,76 cm/s (1-7/8 ips) ±0,5%

Wow and Flutter:  less than 0,03% (WRMS); 0,08% (DIN 45500)

Frequency Response

LN Tape :  25 to 15,000 Hz ±3 dB (-20 VU)

LH Tape :  25 to 17,000 Hz ±3 dB (-20 VU)

CrO₂ Tape :  25 to 15,000 Hz ±3 dB (-20 VU)

CrO₂ Tape :  25 to 9,000 Hz ±3 dB (0 VU)

Metal Tape :  25 to 21,000 Hz ±3 dB (-20 VU)

Metal Tape :  25 to 13,000 Hz ±3 dB (0 VU)

Total Harmonic Distortion (1,000 Hz "0" VU):

LN Tape :  less than 0,8%

LH Tape :  less than 0,8%

CrO₂ Tape :  less than 0,7%

Metal Tape :  less than 0,6%

Signal-to-Noise Ratio :

LN Tape :  better than 58 dB

LH Tape :  better than 60 dB

CrO₂ Tape :  better than 61 dB

Metal Tape :  better than 62 dB

Erase Ratio:  better than 70 dB

Bias Frequency:  100 kHz

Heads:  Super GX recording head Super GX playback head and erase head (3 head System)

Motors:

Capstan Drive :  One FG servo DC motor (Direct Drive)

Reel Drive :  one DC motors

FF and Rewind Time:  60 sec. Using a C-60 cassette tape

Output (Jacks)

Line :  410 mV (0 VU). Required load impedance :  more than 20 k Ω

Phone :  100 mV/8 Ω

Input (Jacks)

Microphone :  0,25 mV (Input impedance 4,7 k Ω ). Required microphone impedance :  600 Ω

Line :  70 mV (Input Impedance 100 k Ω )

DIN Jack:

Input :  2 mV (Input Impedance 10 k Ω )

Output :  0,3 V Required load impedance: more than 20 k Ω

Power Requirements:  100 V, 110/120/220/240 V switchable, 50/60 Hz

Power Consumption:  38 W (JPN, CSA, AAL) 

Dimensions (W x H x D):  440 x 105 x 370 mm (17,3" x 4,1" x 14,6")

Weight:  9,8 kg (21,6 lbs)