aCA7.5

Representing many hours of painstaking component tuning, the Cyrus aCA7.5 preamp is the most capable partner for our separate power amp models. Digital control of volume and system command ensures this audiophile control amp provides seamless system control. Features include intelligent headphone control, input level adjustment and PSX-R port.

Building on the success of the critically acclaimed aCA7 pre-amplifier, the aCA7.5 is the result of a review by the Cyrus design team. The new aCA7.5 takes the performance of our Cyrus aCA7/aPA7 amplifier system still further with subtle changes to the sensitive audio signal circuitry and layout further enhancing musical transparency and presentation. An aCA7.5 set up with a partnering PSX-R power supply and twin aPA7s offers Cyrus devotees the very best in sound quality, user convenience and system flexibility, housed in the unique and stylish Cyrus precision casting. The perfect combination of straight line approach with micro-processor controlled operation makes the Cyrus aCA7.5 a world class preamplifier.

Straight line, short path passive technology for input selection circuitry first developed for the Cyrus Pre goes a long way in establishing a sound foundation for the aCA7.5 to build on. The new generation of sub-miniature components selected by Cyrus have yielded a further reduction in circuit area and PCB path lengths. The passive approach for signal switching ensures an undisturbed, low impedance path for the low level input signals through miniature relays with gold switch contacts. The low current actuator coils of the relays ensure zero power supply related imprint on low level signals potentially caused by actuator coil coupling.

Two tape circuits are included within the comprehensive input selection options of the aCA7.5. Tape 1 is designed for use with two-head cassette decks or with the new generation of digital recording systems, Tape 2 offers the extra facility of full off-tape monitoring for a three-head analogue open-reel tape recorder or cassette deck equipped with separate recording and playback amplifiers.

The digitally controlled analogue volume control features laser trimmed resistor networks whose production accuracy allows excellent channel matching – particularly at low volume settings. The volume control also features a zero cross detection circuit which ensures that the volume setting is only changed at the point where the audio signal passes through zero, this ensures complete elimination of the zipper noise often associated with electronic volume controls.

Technical Information

Electrical

Line inputs – 5 + 2 Tape
Pre-amp Outputs – 2 Preamp-out (RCA phono sockets), Balanced out (XLR sockets)
Tape Outputs – 2 Tape-out
Headphone Output – ¼” Jack
Power Supply – Toroidal transformer with low noise double bridge rectification
External – Highly regulated PSX-R upgradeable
Communications – MC-BUS™ System BUS
Remote Control – Full function, supplied with Cyrus Audio Commander system remote

Specifications

Output voltage – (Max level) 380mV (RCA), 775mV (BAL)
Preamp Output – impedance 75 Ohm (RCA) 22+22 Ohm (BAL)
Distortion – 0.002% (20Hz-20kHz inc. hum)
Frequency Response – -3dB at 0.1Hz and 88kHz
Line input sensitivity – 200mV (RCA)
Line input impedance – 50 kOhm
Line s/n ratio (ref. 500mV) – 105dBA
Dimensions – (H x W x D) 73 x 215 x 360 (mm)
Weight – 3.1kg
Finish – Black

Designed & Engineered in the United Kingdom