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





Sherwood S-5000

 The "new" Sherwood S-5000 dual amplifier preamplifier makes possible either stereo or monaural high-fidelity systemoperation with only one set of basic coordinated controls, yet offers every important control feature essential to both stereo and monaural operation. These include 10 two-channel controls, stereo normel/revers switch, phase inversion switch, and dual amplifier monaural operation with either set of input sources. The five modes of operation; stereo, stereo-reversed, monaural 1, monaural 2, monaural 1 + 2, are selected by the function switch which also operates a corresponding group of indicator lites to identify the selected operating mode.
All controls operate both channels simultaneously. In addition, the bass and treble controls feature friction-locked shafts which also allow the adjustment of one channel separately from the vertical rumble and noise components balanced out. A tape monitor switch permits instant comparison of recording input signal to tape with recorded output from tape when used with recorders offering monitor heads.
 Special features:
Stereo-monaural indicator lights
Dual/single bass and treble control
Compensated ganged loudness control
Plays monaural records with vertical rumble and noise balanced out
Stereo normal/reverse switch
Phase inversion switch
Ganged presence rise switch
Ganged phono and scratch filter switches
Ganged tape monitor switch
Stereo balance controls both channel
Six high level inputs
Four phono/tape preamp inputs
3rd channel output
Two tape monitor inputs and recording outputs
Speaker damping factor selection
Color coded cables and receplacles
 The Model S-5000 also can be used as a 40 watt monophonic "starter" system planned for later conversion to a 20 + 20 watt stereophonic system. The interchange from a 40 watt single amplifier to a 20 + 20 watt dual amplifier is accomplished by a single front panel switch. This circuit connection features the full sum of the 2 separate amplifierrs' outputs instend of using the power-robbing parallel connection commonly used.
All Sherwood amplifier now provide selectable damping factors of 10/1 (normal) or 2/1 (for use with today's popular compact speaker systems).
 The Sherwood S-5000 Function Selector operates its associateed indicator lites to identify the source-speaker combination selected. This exclusive feature, which also serves as the off-on pilot lite, tells at a glance which stereo or nonaural function has been selected as shown in the chart at right. Note especially the last position, :Mono S1 & 2" which connects a stereo phono pickup in such a manner that the vertical rumble and scratch components are balanced out for use with monaural records.

Important aids to flexibility of stereo system operation are the bass and treble controls included in the Model S-5000. each control features friction locked dual knobs. With normal usage, the main knob on each control operates both left and right hand channels  simultaneously due to its friction-locked concentric shafts. In addition, one channels tone may also be adjusted independently of the other. This is possible, because the 2nd-channel indicaqtor knob can also readily be adjusted without moving the 1st-channel knob as permitted by the friction -locked shafts. Afyer this independent adjustment, both channels  are again automatically ganged together for simultaneous operation by the main knob without upsetting the inter-channel relationship selected.
Specifications:
Power Output:
Monaural :  40 watts (80 watts peak) at 1½ %  IM distortion.
Stereo :  20 + 20 watts (40 + 40 watts peak) at ½% THD or 1½%IM distortion
Outputs:  16, 8 and 4 Ω for left and right speaker, 2 cathode follower recording outputs
Inverse Feedback:  18 dB
Damping Fcator:  10 : 1 normal
Frequency Response:  20 cps to 20 kc ±0,5 dB (at 20 + 20 watts)
Tone Control Response:  flat Setting, 20 cps to 20 kc ±½ dB
Tone Control Range:
At 15 kc :  20 dB boost or cut
At 40 cps :  16 dB boost, 19 dB cut
Rumble Filter:
At 27 cps :  18 dB rejection
At 100 cps :  less than 1 dB down
Preamp Equalizer Curves:
RIAA phono;  NAB tapehead, others w/tone controls
Controls and Switches (all controls and switches operate both channels):
Loudness control w/loudness compensation switch, dual/single bass and treble controls, stereo balance, presence rise, rumble-filter, and scratch filter switch, phono level, function switch selector switch, tape monitor switch, and output tube balance.
Balance Control range:  ±45 dB
Interchannel Crosstalk:  less than -50 dB at 1 kc
Sensitivity: 
Tuner :  0,20 V
Phono :  2 mV (adjustable with phono level control)
Max. Input Capability:
Tuner :  10 V for less than 1% IM distortion
Phono :  200 mV for less than 1% IM distortion
Max. Hum and Noise (volume controlat min. 90 dB weighted below rated output.)
Tuner Input  (controls max.):  80 dB (weighted) below rated output
Phono Input (control flat):  60 dB below rated output; 72 dB below 10 mV
Power Consumption:  at 110 - 120 V,  60 Hz is 110 W
Dimensions (W x D x H):  14 x 13 ½ x 4 inch

Weight:  29 lbs (shipping)

1 commento:

  1. I have this exact amp in the shop now being refurbished. 6 months and still waiting... hoping for stellar results.

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