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





McIntosh MC 2002 power amplifier

Power Amplifier. 

 The MC 2002 amplifier is designed for the Real world of 10 decibel overloads from compact disc players. It combines: 200 watts of extremely low distortion power at 8 ohms; 300 watts of the same power at 4 ohms. The greatest reliability in modern amplifiers to protect your investment. And most important today, design for 10 decibels of overload stress with the greatest Spectral Fidelity.

Spectral Fidelity is one of the most meaningful characteristics of an amplifier. The harmonic distortion and the two tone intermodulation measurements are important criteria in predicting the sonic performance. However to obtain better correlation with human hearing response, we need to know not only the energy in the distortion spectrum, but also the number of discords and their frequency spacing from the desired tones. This is what the Spectral Fidelity testing can do, enlarging the scope of the data and showing its meaning more fully.


Spectral Fidelity Protection

The threshold for human hearing shows a pronounced sensitivity in the region of 1500 Hz. At low levels of music, during pianissimo passages for example, is where we hear most intermodulation discords. But during the periods of sonic overload, this sensitivity characteristic changes. Under this condition, the sensitivity of the human ear becomes more uniform over most of the range of hearing. Thus all of the discords from sonic overload combine to reduce the musicality of instruments and voices, their clarity and definition. This loss of the order, the structure, and harmony, remebered from live musical experience, is frustrating and disappointing to the human psycho=physical hearing phenomenon. This frustration is the major cause of unacceptable  Listening Fatique.

Of all the amplifiers tested for Spectral Fidelity under stress, the McIntosh alone could accept the compact disc overload without exceeding 3/10 of 1% distortion. The others produced high levels of distortion, distortion from 20% to 30%. Some designs blew fuses. Others suffered output stage device failures.

 


Specifications

Power Output: 

Stereo :  200 watts into 8  loads or 300 watts into 4  loads is the minimum sine wave continuous average power output per channel for 20 Hz to 20,000 Hz with both channels operating, which is:

40,0 volts RMS across 8 oh or 34,6 volts RMS across 4

Mono :  600 watts into an 8  load, is the minimum sine wave continuous average power output from 20 Hz to 20,000 Hz, which is 69,3 volts RMS across 8

Output Load Impedance

Stereo :  4  to 8

Mono :  8  obtained by connecting across the output terminals of both channels

Rated Power Band:  20 Hz to 20,000 Hz

Total Harmonic Distortion

Stereo :  0,01% maximum harmonic distortion at any power level from 250 milliwatts to rated power per channel from 20 Hz to 20,000 Hz, both channels operating

Mono :  0,01% maximum harmonic distortion at any power level from 250 milliwatts to rated power from 20 Hz to 20,000 Hz

Intermodulation Distortion

Stereo :  0,01% maximum at any power level from 250 milliwatts to rated power with both channels operating, for any combination of frequencies from 20 Hz to 20,000 Hz

Mono :  0,01% maximum at any power level from 250 milliwatts to rated power for any combination of frequencies, 20 Hz to 20,000 Hz

Frequency Response (at 1 watt output):

20 Hz to 20,000 Hz  +0 -0,25 dB

10 Hz to 100,000 Hz +0 -3,0 dB

Hum and Noise:  100 dB below rated output 90 dB IHF

Ratings IHF Dynamic Headroom:

2,1 dB at 4   load

1,7 dB at 8  load

Damping Factor:  greater than 100

Input Impedance:  20,000

Input Sensitivity:  Switchable for either 1,4 Volt or 2,5 Volt

Power Requirements:  120 Volts, 50/60 Hz 0,6 to 15 ampers

Dimensions

Front Panel (W x H) :  411 mm x 181 mm (16-3/16" x 7-1/8")

Chassis :  375 x 165 x 368 mm (14-3/4" x 6-1/2" x 14-1/2")

Finish:  Front panel is anodized gold and black with special gold/teal nomenclature illumination. Chassis is black

Weight (net):  22,7 hg (50 pounds)

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