The Fisher 400 pe tuburi (lampi) Stereo tube receiver

Vand The Fisher 400 -receiver pe tuburi, alimentare pe 110 Volti!

Original din US, nereparat niciodata, in perfecta stare de conservare si functionare, sunet fara brum, fasait sau alte zgomote din potentiometre, etc. Pozele sunt originale. Nu trimit in tara datorita greutatii si riscului cazaturilor. Se face proba la domiciliul meu. Compatibil 4,8, 16 ohmi.

When considering the origins of High-Fidelity, the names Avery Fisher,  Herman H. Scott, Rudy Bozak, Frank McIntosh, James Lansing, Jim  Stephens, Paul Klipsch, Saul Marantz, David Hafler, and a few others  come to mind. Of those people the single most prominent figure  responsible for its success is Avery Fisher.

Fisher was born in the  Yorkville section of Manhattan into a family to whom music was an  important part of recreational life. His father, Charles Fisher, a real  estate specialist, owned one of the nation's biggest collections of  acoustic horn gramophones. The boy Avery was allowed to study the violin as early as he wanted to, which was pretty early. As Fisher grew so did his proficiency of the violin, often participating as a first or second fiddle, at a nearby chamber music concert hall with visiting companies. Despite this musically bent upbringing, when he went to NYU he majored  in biology, then went an entirely different direction for his first  profession, a book and typographical designer at Dodd, Mead and Company, book publishers. Avery became very good at this, designing many  successful books, although his desire for music and the ability to  electronically reproduce it as accurately as possible got the best of  him. After years of tinkering around with audio circuits in his free  time Avery successfully developed audio equipment capable of  outperforming the professional equipment standards of the day. By 1937  his profession (book designing) and avocation (high fidelity) exchanged  places and he founded one of the first audio companies devoted to  developing high-grade components for home use, Philharmonic Radio  Corporation (PRC).

At PRC Avery produced components of uncommonly high quality and his company was quite successful from the get go.  However, with the onset of WWII the entire consumer audio and radio  industries came to a halt virtually overnight. Like so many other  companies PRC shifted its production to that of electronic mechanisms  for war. At this time Avery sold his company to a big corporation,  although he continued to direct it through the duration of hostilities.

Despite the many horrors the war brought to the world, one of the positive  things it contributed was the technical knowledge gained from six years  of wartime laboratory research. In 1945, after the war ended, Avery  refocused his attention back to music. Armed with his newfound  expertise, and a handpicked design team of  the brightest engineers of  Europe, he incorporated his 2nd company, the Fisher Radio Corporation.

Out of a small shop in New York City Avery Fisher peddled custom made  High-Fidelity equipment long before most people knew what that phrase  meant. He revolutionized audio circuitry inventing much of the  technology that we widely use today. As word of mouth grew so did  Fishers fame, eventually his equipment became known as the Rolls Royce  of the audio industry. He compiled a long list of noble clientele,  including heads of state, celebrities, and accomplished musicians.  Throughout the 40’s,50’s and 60’s if one wanted the finest in audio,  there was no question who made it, Fisher.

The Fisher 400  Stereophonic FM Receiver was released the same year as the 500c,1964.  Fisher feared the $390.00 projected selling price of 500C would scare  away a large portion of potential customers, so he designed the slightly lower powered 400 and sold it for $330.00.  $330.00 was still a lot of  money in the early 60’s, although the performance to dollar ratio of the 400 was the best to be found in that era.

Just a year prior to  the release of the 400 & 500c, Fisher showed the world true  hi-fidelity reproduction was possible in an all-inclusive component with the 500B receiver. Building upon the strengths of that receiver, Fisher tweaked the design, taking advantage of a, then, relatively new output  tube, the 7868. By using the 7868 tubes in a push-pull configuration, he reduced the power output by only 4 watts, although this allowed him to  use slightly smaller transformers, which is how he was able to shave off most of the extra cost.

Sonically the 400 & 500C are pretty  close, each having their own strengths and weaknesses, although the 400, with its 7868 output section, is favored by many for its ability to  present music with a degree of naturalness and effortlessness superior  to the 7591 designs. Overall the sonic quality of the 400 is very hard  to beat. Like the other classic Fisher receivers its sound is warm and  extremely musical. Bass is punchy yet polite, highs and mids are cleanly depicted with amazing detail. It is rated at 30 watts per channel;  although that is a very conservative rating, it puts out plenty of  real-world juice. Other features and functions of the 400 include:

Nuvistor-Golden  Synchrode  front-end

A FM breakthrough and an important reason for the 400’s phenomenal FM  performance. The Nuvistor-Golden Synchrode affords very high  sensitivity, a wide overload margin,  and  better rejection  of   spurious  and  image signals  than other designs. Low-noise  Nuvistor  triodes, used for both mixer and oscillator,  provide a  higher  degree  of  mechanical and electrical stability,  and a  better  signal-to- noise  ratio.  The signal is then amplified  by four wide-band  IF  stages  and  is converted  to an audio signal  by  a  wide-band ratio  detector that utilizes  two  balanced germanium  diodes.  The high  amplification of these IF stages, combined with  the  progressive action  of  three limiters  (including  the ratio detector), assures a maximum degree of  freedom from noise and interference.

The  Preamplifier  Section

offers a  full complement of  audio controls, including separate   friction-lock  bass and  treble controls, high sharp-cutoff filters,  loudness contour, plus a  front-panel headphone  jack. There are a total of 4 inputs: two phono inputs, a tape-head input, and an Aux input  allow you to handle any source component, modern or vintage.  The Phono  Preamp section uses one 12AX7 tube per channel for about 20dB of  amplification.

Power Amp Section

utilizing four Novar-type 7868 beampower pentodes in push-pull  configuration for a full 65 watts of Music Power (IHFM standard)  at   extremely  low  distortion,  with outstanding transient  response  and   stability. At normal listening levels the distortion is virtually  nonmeasurable.  It is inaudible at all levels.  Advanced circuitry is  combined with superior, oversize output transformers to make this  performance possible.  A derived 'third' power output is provided in  addition to the left and right speaker connections, for either  center-channel use or an extension speaker.

Superior Output Transformers

The 400 utilizes high grade output transformers with grain-oriented,  laminated steel cores. As the heart of the amplifier it is of highest  priority to not skimp here, as most manufacturers did.

Loudness Contour 

The Loudness Contour switch provides compensation for the decreased  bass sensitivity of the human ear at low volume levels. Scientific tests by Fletcher and Munson have established certain average amounts of bass that should be added to the musical signal at low volumes. When the  Loudness Contour switch is turned ON, this compensation is automatically added to the signal and automatically varied, according to the setting  of the Volume control.

And Much More!

SPECS

FM TUNER

IHFM  usable sensitivity: 1.8 microvolts. Selectivity: (alternate channel) 60  dB. Signal-to-noise ratio and hum: 70 dB. IF rejection at 100 MHz: 85  dB. Spurious response rejection: 90 dB. Image rejection: 57 dB. Capture  ratio: 2.5 dB. FM Harmonic distortion at 100% mod: 0.5%. Calibration  accuracy: 0.2% FM Channel separation (stereo): 35 dB.

AUDIO SECTION

Music  power: (IHFM at 1 kHz and 0.5% third harmonic distortion, 65 Watts total RNIS power at 1 kHz and 0.8% THD). One channel driven 30 Watts; both  channels • driven 50 Watts. Intermodulation distortion: (60/7,000 Hz,  4:1); at 30 Watts, each channel 0.8%; at 50 Watts, both channels 0.8%.  Frequency response: overall 25-25,000 Hz. ± 1 dB; power amplifier  section 10-40,000 Hz. ± 0 dB — 2 dB. Hum and noise: below RMS rated  output 80 dB. Channel separation: at 1,000 Hz, 50 dB. Bass controls:  variation at 50 Hz, 22 dB. Treble controls: at 10,000 Hz. 22 dB. Fixed  subsonic filter: 12 dB/octave below 18 Hz. High filter: — 3 dB at 5 kHz  12 dB/octave above 6 kHz. Input sensitivity: (for rated output) Phono  Low 4.4 rnV; Phono High 14 mV; Tape head 2.8 mV; Auxiliary 280 my. Tape  monitor: switch on 1.15 V; Selector at Aux-Tape 440 mV.