SONY STR-7800SD (1977) | LEC Transistor

The STR-7800SD introduced by Sony in 1977 seems to be a rather rare unit that was aparently only distributed to the U.S. market. According to a Sony advert from 1977: "Even before you switch on the STR-7800SD receiver, it'll be receiving. Receiving oohs and aahs." It continues by saying: "...it is the finest receiver ever designed by Sony." The 7800 puts you on the receiving end of the most tomorrow-looking technology available in 1977. The 7800 brings power to the power-hungry, and can even make the mild-mannered lust for power. Rated at 125 watts per channel, it's powerful enough to drive any speakers-satisfy any need. The 125 watts, minimum RMS at 8 ohms, is from 20 to 20kHz-with no more than 0.07% Total Harmonic Distortion. How this combination of power and low distortion was achieved, is an example of Sony's engineering muscle. Starting with the toroidal transformer. A more efficient structure, it fully exploits the high-performance power amp. As do two over-sized capacitors, each 22,000uF. So the feeling of power throughout the frequency range is unmistakable. You'll receive tuning that'll leave you swooning. FM circuitry found usually in separates appears in the 7800. Pardon for the initials, but MOS FET's are used in the FM RF amplification. The result: good linearity, low noise and high sensitivity. For FM Dolby listeners, a complete FM Dolby noise reduction system is available, to minimize noise and overload distortion. A Multipath switch and meter indicate optimum antenna orientation, thereby reducing distortion. An LED dial pointer doubles in length when an FM signal is received for easy tuning. You'll receive a pre-amp that's pre-eminent. High marks for Sony's Low Emitter Concentration (LEC) transistor. Designed, made by, and exclusive to Sony. It guarantees low noise, and a wide dynamic range. It also keeps RIAA equalization to within ±0.5dB. You'll receive power. And the means to control it. The pre-amp section also gives you the control you need to keep all that power in line. A presence switch is a special present: it lets you equalize the mid-range. Importantly, the 7800 was built with a Professional Attenuator Main Volume Control. It eliminates gang error between channels. Some input on the inputs: Phono 1, Phono 2, External Adaptor, Auxilliary, two tape decks - and tape-to-tape dubbing facilities. Specifications: Continuous power: 2x125W (RMS, both channels, 20-20.000Hz, 0,07%) | THD: 0,07% | Dimensions (W/H/D) 490x170x515 mm | Weight 22,8kg | Original sale price 700 US-$

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Technics RS-B900 (1991) | G-Series

 

The Technics RS-B900 is a stereo cassette deck with a closed-loop dual capstan system and three heads. The mechanism employs a closed-loop dual capstan system, with a high-torque Quartz controlled DD motor providing excellent rotational precision and stable running performance. The recording amplifier employs Technics' proprietary discrete linear magnetfield Class AA, consisting of a voltage-controlled amplifier and a current-supply amplifier, significantly improving the magnetic field waveform response. The playback system is equipped with a phase correction circuit to ensure a more faithful waveform response. A CD direct line input terminal is also provided to record CDs without compromising their dynamic range. The mounting frame supporting the transport system effectively combines two different materials, die-cast zinc and die-cast aluminum, for superior vibration resistance. In addition, power-assisted cassette loading securely holds the highly rigid, glass-fiber-reinforced cassette holder in place, while cassette half stabilizers suppress vibration of the half itself caused by tape movement. The internal structure features a T.N.R.C. base with excellent vibration damping properties and an anti-vibration top panel, reducing external and internal vibrations. A separate block structure prevents mutual interference. This structure separates the power supplies for the mechanism control system and the audio system, and further divides the audio system into five blocks: playback equalizer, playback noise reduction, recording noise reduction, recording equalizer, and headphones, preventing signal interference from adversely affecting sound quality. Beat noise is reduced by incorporating a BS bias that drives the bias at a high oscillation frequency of over 200 kHz. The RS-B900 also features APRS (Advanced Precise Rec Level System) functionality. When a signal is input while in record pause mode and the APRS button is turned on, the maximum input signal value is held and displayed on the meter. Adjusting the Rec-Level to match this displayed maximum value will cause the hold indicator on the meter to move accordingly, allowing you to set the appropriate recording level. The level meter features a switchable range, allowing you to change the level display in 1dB steps. A built-in recording calibration oscillator allows you to adjust the recording level and bias for each left and right channel. In addition to Dolby B/C, the noise reduction system also includes dbx, which provides excellent noise reduction. The recording/playback combination head uses an amorphous head with PC-OCC windings. Dolby HX-PRO is included for improved high-frequency recording characteristics. A linear electronic counter is included, allowing memory stop and memory repeat functions. An MPX filter is included. An auto tape/source monitor is included. A wireless remote control is included. While this model is based on the RS-B965 it was actually only made to order for Japanese market customers. Specifications: 3-Head System, Amorphous heads | Quartz Direct Drive Dual Capstan in a 2+1 motor mechanism | Wow & Flutter 0,03% WRMS | Dimensions (W/H/D) 483x141x290 mm | Weight 7,5kg | Original sale price in Japan ¥100,000

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Victor (JVC) Mezzo Prezio micro (1990)

This is an amazing micro Hi-Fi system introduced in 1990. It was known as the Victor Mezzo Prezio in Japan and JVC Super Digifine micro Worldwide. The components of this system are: FX-105 (FX-V1TN) Computer-Controlled Digital Synthesizer tuner with 40 random preset memory, 16-character alphanumeric display for station names and frequencies, remote control card with numeric keypad - TD-105 (TD-V1TN) 3-Head Dual Capstan Computer-Controlled cassette deck with Dolby B-C HX Pro, fluorescent digital peak display and remote control card - EX-105 (EX-V1TN) Digital Processing Control Amplifier with Dolby Pro Logic Surround, Digital Acoustics Processor, Input 6-audio and 5-video, on-screen display, dot-matrix fluorescent display, 2 unified A/V remote control cards - ME-105 (ME-V1TN) Dynamic Super-A Power Amplifier, 2x80W 4ohm + 50W centre channel + 2x30W rear, discrete 5-channel amplifier, automatic 2/5 channel operation - SX-105TN 2-Way 3-Speaker bass reflex loudspeakers with two 12cm "metal cone" woofers and 2,5cm Titanium dome tweeter.

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