Yamaha CA-610

 Pure Power Boots Listening Pleasure

In the trend towards higher output powers, the CA-610 is unique. The minimum 40 Watts per channel is generous. With most home listening done between 1 and 10 Watts it can even be overwhelming. But the tremendous sense of scale, of unstrained ease in reproduction, and vast reserves of power, is more than you would expect from 40 Watts (and certainly more than you would get from most competitive amplifiers in the same class).

Capable of recapturing for you the thrill of an orchestral ‘tutt’ or a live rock concert the sound is never choked in noise or smeared with distortion at low levels.

From a mere 250 mW up to the full rated output of 40 Watts, and for all frequencies from 20 Hz to 20 kHz, the CA-610 gives no more than 0,05% THD. At 20 Watts output that drops to 0,01% (0,005% at 1 kHz) And signal-to-noise ratio is 75 dB for a 2.5 mV phono input. It all adds up to a new experience in impressive, powerful reproduction. The meters cover outputs from 0,01W to 100 W in one unswitched range a valuable feature that lets you know how much power your speakers are handling.

  Ultra Low Distortion Tone Control Circuitry.

The CA-610 tone controls offer the ideal combination of characteristics; simple to operate, they add virtually no distortion to the final sound. You can boost or cut treble and bass to suit your mood, your choice of music, or the acoustics of your room and speakers. And you can do it all without sacrificing quality for the convenience.

The special Yamaha negative feedback circuitry, and perfect crystal device trchnology used in the semiconductors, give smooth and precise control, with perfectly flat ‘0’ (zero) position. And so that you can compare the effects of your tone control settings, there are separate ‘defeat’ switches for bass and trebl, instantly bypassing the boost and cut circuits. Thespecial Yamaha design ensures that distortion is held to a minimum, typically contributing only 0,008% from 20 Hz to 20 kHz with 90 dB S/N ratio and 0,4 mV residual noise for the Aux terminals.

Music waveforms are incredibly complex, and the pulse plus sine wave response of the CA-610 shows how faithful reproduction of such signals is.

Clearly Audible Advance in Quality

The CA-610 is more than the sum of its parts. More than a combination of superb equalizer amplifier for record reproduction, sophisticated tone controls, and a powerful main amplifier. It’s truly integrated. And not only is power high, the distortion hits new lows at all listening levels form the quietest to the very loudest.

A Fantastic Range of Operating

The Ca-610 combines full tape monitoring and dubbing facilities with a new ability. Now, not only can you copy direct from one tape deck to another in any direction, and monitor recordings while they are being made  (if you have a three-head tape deck), You can also listen to any program source while you are recording. This lets you save time by dubbing at double speed, while relaxing to the sound of your favorite record. Or your can record an FM program for later audition while listening to a pre-recorded tape.

More Than an Amplifier  - A Complete Control Center

If you hear the Ca-610 you can hardly fail to want it. If you select it, you are sure to want the matching tuner; the CT-610. Together, they stand right at the top of their class, and from the nucleus of a first quality home stereo system.

The CA-610 has  a precision volume control, perfectly in balance within +_1 dB form 0 to -70 dB, with an attenuation curve that makes it easy to set the exact level you want. Then there is the -20 dB muting switch for an instant cut in volume. And the useful Rec Out Off position, cutting out the effect of tape decks when not recording. A host of useful features.

Advanced Equalizer Design

With its four-stage direct-coupled configuration, the equalizer resembles power amplifier design more than it does conventional circuitry. All four stages (differential current-mirror first stage plus emitter/ collector/ emitter-follower) operate under constant current bias, and give excellent open loop performance. The result is high stability and ultra-low distortion with moderate NFB for superb dynamic characteristics.

Sophisticated Amplifier Design

The combination of differential current-mirror first stage, and common emitter plus Darlington-connected fully symmetrical complementary output-capacitorless (OCL) output stage, with careful choice of high performance, low input capacity transistors in closely matched pairs, gives power amplifier performance virtually indistinguishable from Class A operation. Low frequency response is improved by separate power supplies for differential amp., pre-drive, and power stages, via two 6,800 uF smoothing capacitors.

Specifications

Continuous Min. RMS Power (both channels driven at rated distortion, 20Hz-20kHz):

50 + 50 Watts at 4 Ω

40 + 40 Watts at 8 Ω

Total harmonic Distortion:  0,05% or less (rated output)

Intermodulation Distortion:  0,05% or less (rated output)

Power bandwidth (IHF, both channels driven):  10 -50 ,000 Hz

Damping factor (8 Ω, 1 kHz):  better than 50

Output Terminals:  A, B or A + B (front panel switch)

Speaker Impedance:

A or B : 4 to 16 Ω

A + B : 8 to 16 Ω

Frequency response (Aux to Sp. Out):  20 Hz - 20,000 Hz  +0,2  -0,3 dB

RIAA Deviation: 20 Hz - 20,000 Hz ±0,3 dB

Signal-to-noise Ratio (IHF-A  network):

Aux to Sp. Out : 90 dB

Phono to Sp. Out : 75 dB

Residual Noise (Pre + Main Amp , 8 Ω):  0,4 mV

Input Sensitivity/Impedance:

Phono : 2,5 mV/50 k Ω

Tuner, Aux tape PB ( 1,2) : 150 mV/50 k Ω

Phono Dynamic Margin (1 kHz,0,1% THD) : 150 mV/1 k Ω

Output Level/Impedance:

Tape Rec Out (1, 2): 150 mV/1 k Ω

Tone Controls:

Bass : ± 12 dB boost/ cut at 50 Hz

Treble : ± 10 dB boost/ cut at 10 kHz

Loudness Control (volume -30 dB):  50 Hz : +9 dB, 10 kHz : +5 dB

Subsonic Filter:  -3 dB at 25 Hz (12 dB/oct)

Audio Muting:  -20 dB

Semiconductors:  4 Ics; 29 Transistors; 13 Diodes plus 3 Zener Diodes;

Power Source: 110/130/220/240 V AC switchable, 50/60 Hz

Power Consumption:  105 Watts

Dimensions (W x H x D):  435 x 150 x 298 mm (17⅛" x 6" x 11¾")

Weight:  8 kg (17,6 lbs)