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Decuphase C-260 ENTO EENE ol Bs, ER The unparalleled performance of the new Accuphase C-260 Stereo Control Center sets a new standard for the times. Dependability is built in with features such as Class-A push-pull circuits with exclusive power supplies that control line amplifiers for a balanced transmission system. And the complete twin mono construction incorporates independent power transformers. The versatility of the innovative C-260 makes it a unique and powerful stereo control center. A preamplifier or a "Control Center", as we call it source of sound deterioration, The resistor element operated in the balanced signal transmission con- here, ls positioned between the power amplifier and of the control is polished very precisely to reach a nection as shown in Fig. (a). Even when unbal- such musical sources as a CD player, analog turnt- mirror-like smoothness. This newly employed vol- anced external equipment is connected to the in- able, tuner, DAT recorder, etc., conveniently con- ume control rotates the resistor elements unlike the puts, outputs or both, the new balanced line am- trolling the signal traffic and adjusting the signal conventional volume control, in whioh the collectors plifier circuit of the C-260 simply grounds the nega- volume to any desired level. This is the main func- rotate. Thus, it successfully reduces the number of tive signals, while maintaining its original circuit tion required of a preamplifier. However, it must metal joints, which have been a source ol sound configuration functioning fully as an ideal balanced transmission system. In other words, the circuit, also provide absolutely uncolored sound reproduc- deterioration, resulting in a remarkable improve- tion whereby the listener will not even notice its ment of the distortion characteristics. through which signals pass, remains the same existence. The C-260 provides a numobf feuncrtio ns worthy whether or not it is used with balanced or unbal- Employed by the very first model of the C-200 to its designation as a "Control Center”. All func- anced connections, thus successfully eliminating series preamplifiers is ap ure complementary push- tions, other than those most commonly used, are any changes in the signal path that may deteriorate pull amplifier circuit, a truly ideal amplification cir- logically organized under the hinged front sub- sound quality. panel. This assures the utmost ease of operation This ideally balanced circuit based on the signal cuit topology. As the series advanced, such addi- tional circuit features as a direct coupled and cas- while maintaining a simple overall appearance. transmission theory, guarantees remarkably im- code bootstrap circuit were added. Further, a bal- We are confident that the C-260 Incorporates all proved S/N characteristics, thanks to the excellent anced signal transmission circuit was very quickly the technical know-how that Accuphase has noise reduction when employed in a balanced con- employed for both the input and output stages, in accumulated since its foundation. It combines nection order to further improve the audio quality. superb performance characteristics, excellent op- In the C-260, the circuit perfection has been erational functions and beautiful design, allo fwh ich Excellent Basic Characteristics for Line Input furthered by successfully developing an output cir- have been refined to their utmost, bringing you a ‚Amplifier step higher in the fascination of sound reproduc- Fig, 3 shows a circuit diagram for the balanced cult consisting of a single amplifier and no transformer. This is an ideally balanced signal transmis- tion input amplifier. It is based on Accuphase's original sion circuit, which does not require a common differential complementary. push-pull input am- ground. plifier and cascode push-pull amplifier circuits. The Accuphase's original logic relay control circuit High Quality, Ideally Balanced Transmission input stage, in which a high-gm type FET is employ- has been emplotyoec ondtro l compauldieo sxign al Line Amplifier ed, consists of a constant current load type cas- Fig, 1 is a circuit block diagram of the C-260. The ntroatf fice. xpTohsei nrge laythse useeldec tarrice icn oan tsaecatlse d toc asaiirn,g ,w htihcuhs simplified functional explanation of the balanced icnopduet acimrpcluíift.i er,T hew hCe-n2 60t heo pienrpautte ss igansa las baarlea nccoend- guarantees many years of perfect operation and line amplifier stage is shown in Fig. 2. As shown, nected to the positive (+) and negative (—) termi- AMP2 and AMPS complement each other's opera- nals. It operates as an unbalanced amplifier, when high quality sound reproduction. tion. Asa result, no common ground (G) exists in the the input signals are connected to the common Special attention has been paid to the audio circuit, thus forming an ideal amplifier circuit, when volume control, which normally tends to be a big ground and positive terminals. Naturally, these am- A Newly De trol Presence Control Offers a Versatile 4-Point, 6- Frequency Control Fig. 5 Circuit configuration of the Presence Control ono Equalizer Amplifier AC Cartridges Presence control characteristics INTERIOR LAYOUT channel po transformer hannel pow nel fiterc apacitor: innel fi Each amplifier unit and filter capacitors mounted on the mother PC board and peripheral circuit boards Other Features ar quency energy at terist wide range of MM cartridges. The cuit for MM phono cartridge or 36dB for MM Balanced to Unbalanced Transmission Conver- sion Amplifier Exclusively for Tape Output. Highly Reliable Logic-Relays Permit Straight For the tape recording output Loudness and Short Signal Paths. e signal iransi compensator s of thep reamplifier ist or rt b r characteristics n the sam that they tend tod egrade handled. put terminals, to joke, the C-2€ possibilities with ver rogram source Frequency! vith nitroge Unsurpassed Input/Output Versatility For Multi- ‘Sub-sonic filter the relay are a gold p ple Program Sources characteristics speci ly oped unication equipment use wa toa input put com prerequisites of a "€ Luxurious Persimmon Wood Sidepanels Provided are three pa The airs of unbalance 3 t panel (AD) airs e: N The phono equalizer amplifier has a dedicated power supply unit and features an exclusive input circuit compatible with all cartridges, including MM and MC. The logic relay control circuit board incorporates highly rellable sealed relays charged with nitrogen. FRONT/REAR PANELS Remarks "These switched and unswitched AC outlets may not be supplied depending on the safety standards or regulations applicable in the particular country to where the unit is destined. From the 1owling winds of time and change emerges the Accuphase traditior hones polished and shining. Meet the new tradition enrich life through technology GUARANTEED SPECIFICATIONS +L oudness compensator (when the audio volume set to (Guaranteed specifications are measured accordi —— BUANLBAANLCAEN CED C ~3048) ndard AS-490, AD denotes Analog Disc input Performance Guaranty All Accuphase product sp stated + Attenuator + Frequency characteristics UNBALA! = REC OUTPUT BALANCED INPUT: [CD/LINI MMI/MM2] — BALANCED OUTPUT: + Semiconductors 1.0 to6 00,000H a M — UNBALANCED OUTPUT oH +0, = = REC OUTPUT CED INPUT: [CO/T AILINEITAPE PLAY D OUTPUT. ED OUTPUT AD [MC] INPUT Z REC OUTPUT. e Presence controller + Total harmonic distortion 0.005% ( termina + Input sensitivity and impedance Input termin Rated output AD MMT MMz a AO NC 7000, BALANCED ET] UNBALANCED EA + Rated output and output impedance BALANCED OUTPUT: UNBALANCED OUTPUT: TAPE RE! + Headphone jack Sultable impedance 4 to 6000 + SIN and input converted noise Input shor-cireulted Output voltage vs. THD ‘Output voltage vs. THD- (Balanced CD input to balanced output) (Unbalanced CD input to'unbalanced output) AD MN AD MM2 ADC ALANCED BALA BALANCED OUTPUT UNBALANCED OUTPUT TAPE REC 7.0V. RCA jack for AC input + AD maximum input voltage (distortion ratio 0.005%, 1kHz) MM INPUT: 250mV MM2 INPUT: 125mV a E J MC INPUT: Bm + MiAnLiAmNuCmE Dl oOaUdTiP UmTp.e dance 6000 Input voltage vs, THD (MM input to tape output) Input voltage vs, THD (MC input to tape output) ED OUTPUT: 1k) ccupnase ACCUPHASE LABORATORY INC. K915Y 851-0103-00(G3) PRINTED IN JAPAN