Arcam Delta 60 amplifier

The Arcam Delta 60 is a powerful, versatile and thoroughly modern hi-fi amplifier.

The Delta 60 is a worthy successor to the famous A&R A60. England's "classic" integrated  amplifier of the late seventies and early eighties. Famed for its reliability and long life, as well as its fine sound quality, over 30 000 A60s are in everyday use worldwide. By making use of the advances in technology that were not available when the A60 was designed, the Delta 60 retains all that was best in that amplifier, whilst improving on it in terms of sound quality, aesthetics and ease of use.

The Delta 60's clean design makes it a perfect match for the Arcam Delta series of hi-fi components. These include the Delta 70 compact disc player (with its optional Delta Black Box outboard D/A cenverter) and the Delta 80 FM/AM Tuner. the Delta 60 is also ideally suited to driving Arcam's range of loudspeakers.

Versatility

The Delta 60 can accept inputs from up to 5 different sources. These include 4 line inputs, normally compact disc, tuner and two tape recorders (one of which can be a VCR). A full tape monitor facility for one of the tape recorders is provided, allowing offtape monitoring of the recorder signal when a three head tape recorder is used. Two tape outputs are available.

the disc input caters for all Types of pickup cartridge. As well as normall MM cartridges, even the highest quality low output moving coil types can be accommodated via the Delta 60's built in low noise MC preamplifier stage. this is switchable from the rear of the amplifier. In addition, the user's chosen cartridge may be optimally matched to the disc pre-amplifier by thw addition of our optional switched loading modules. Versions are available to suit both MC and MM cartridges.

All inputs to the Delta 60 are made via good quality phono sockets. All the line level inputs are fed directly to the volume control, enabling any source to be accepted without distortion, as the overload margin is virtually infinite. The volume control itself is a high quality, friction locked "dual" type. This removes the need for a separate balance control (with a consequent improvement in sound qualit). A mono switch is provided; this is operative on all inputs and can yield significant improvements in noise performance when playing old records or receiving weak FM broadcasts.

Ingenious loudspeaker switching is an Arcam speciality. Two pairs of loudspeakers may be used with the Delta 60 - these are connected via heavy duty, silver plated 4 mm sockekets. The main speaker sockets are hard wired directly to the amplifier's outputs to obtain the best possible sound quality. Headphones can be used in parallel with these. A second set of switched loudspeaker sockets is also available; these can be muted via a front panel switch when not required. This is particularly useful for someone who wants to listen to headphones without disturbing the neighbours.

Quality and Reliability

Great care has been taken with every aspect of the Delta 60's design to ensure first class sound quality and reliability. All components are operated well within their ratings and are laid out on a single large fibreglass p.c.b. (printed circuit board). This virtually eliminates internal wiring and connectors, both potential sources of inconsistency and long term unreliability. Most components are soldered using Arcam's military standard flow soldering and p.c.b. washing equipment. This is followed by a rigorous visual inspection procedure. 100% testing of all major parameters is carried out on every amplifier using advanced computer controlled automatic testing equipment both before and after a gruelling 24 hour burn in procedure. After this every amplifier is given a functional listening test by our final inspection department before packing and despatch.

As with all Arcam electronics, the Delta 60 is warranted for 2 years from date of purchase against failure in normal use.

Styling

The Arcam Delta 60 looks as good as it sounds. This is no accident, because great care was taken from the outset with all aspects of both the mechanical and electronic design.

The elegant, slimline cabinet is construced entirely from aluminium alloy with extensive and imaginative use being made of custom extrusions. Aluminium was chosen because of its excellent thermal characteristics (for cooler running) and nonmagnetic properties (for better ssound quality), in addition to its ease and consistency of fabrication. The cabinet is finished in attractive and durable black epoxy paint.

Power

The Arcam Delta 60 is an extremely well behaved amplifier which has a sufficiently high peak current capability to drive all practical loudspeaker loads down to 4 ohms nominal impedance. Electronic protection in the power stages safeguards against  any incorrect loads or short circuits. This short term protection is backed up by easily replaceable output fuses should a fault persist.

The Delta 60 amplifier is guaranteed to deliver its continuous rated output power of 50 watts per channel into an 8 ohm load at any frequency from 20 Hz to 20 kHz. In practice, under normal music conditions, considerably more power is available. Given loudspeakers of at least moderate efficiency, surprisingly high volume levels are attainable without audible distress.

Electronic Design

The Delta 60's electronics incorporate high gain, high current power amplifiers whose inputs are fed directly from the amplifiers's volume control. By eliminating all line amplifier and tone control stages from the circuitry Arcam have ensured that all the Delta 60's line inputs are always routed straight through to the power amplifiers, eliminating the need for such marketing handles as "CD direct" switches and the like. Due to the amplifier's straightwire input the number of series coupling capacitors has been dramatically reduces with consequent improvements in dynamics and clarity.

The power supply meets Arcam's usual high standards with substantial twin 10,000 uF reservoir capacitors fed from a generously sized 200 VA Holden and Fisher toroidal mains transformer. This has excellent regulation and a very low radiated magnetic field for optimum sonic performance.

The phono pre-amplifier stages of the Delta 60 are of a high standard for an integrated amplifier. They feature fully regulated power supplies and a passive equalisation section between the two main stages which are themselves D.C. coupled to each other. This system provides audibly better resolution and imagery. The input buffer amplifiers use precision Op27 amplifiers for improved noise performance and liberal use is made of 1% metal film resistors and high grade polystyrene and polypropylene film capacitors. In addition the Delta 60 incorporates a high quality switchable MC cartridge pre-amplifier stage fed from its own totally separate regulated supply. Provision is made for customised cartridge loading on both MC and MM inputs via Arcam's unique user adjustable universal cartridge loading modules.

Specifications

Output Power

Both Channels :  50 W at 8 Ω  (20 Hz to 20 kHz , 0,5%)

Single Channel :  60 W at 8 Ω , 95 W at 4 Ω

Peak Current Delivery:  ±10A

Harmonic Distortion:  0,02% (50 W, 8 Ω , at 1 kHz)

Frequency Response:

Disc :  better than 40 Hz - 35 kHz  +0,3 -0,5 dB

Typ. -3 dB  at 20 Hz

Line :  30 Hz  to 35 kHz  ±0,5 dB

Typ. -3 dB  at 10 Hz , 80 kHz

Inputs

Disc (Moving Magnet)

Sensitivity :  1,8 mV

Noise (CCIR) :  -75 dB

Overload Margin at 1 kHz  :  35 dB

Input Impedance :  47 k Ω /100 pF

Switchable Loading Module (type ULM/M) available to provide the following additional loads; 30 k Ω , 8 k Ω , 200 pF, 320 pF, 420 pF and user programmable option

Disc (Moving Coil)

Sensitivity :  160 µV

Noise (CCIR) :  -67 dB

Overload Margin at 1 kHz  :  35 dB

Input Impedance :  220 Ω /4,7 nF

Switchable Loading Module (type ULM/M) available to provide the following additional loads; 100 Ω, 30 Ω, 10 Ω, 100 nF and user programmable option

Tuner, Tape 1, 2

Sensitivity: 160 mV

Noise (CCIR) ref. 1 W output -95 dB

Input Impedance: 10 k Ω

Overload Margin at 1 kHz :  50 dB

CD

Sensitivity :  260 mV

Input Impedance :  6 k Ω

Outputs

Tape 1, 2

Nominal  Output :  160 mV

Input IMpedance :  2 k Ω

Crosstalk (all Inputs):  -70 dB at 1 kHz

Power Consumption:  250 VA maximum

Dimensions (W x H x D):  430 x 64 x 295 mm

Weight:  5 kg Net (6 kg Packed)

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