Arcam Comprehensive Guide for A85 Stereo Amplifier Users

Page 17

 

 

 

1

 

 

 

 

2

 

 

 

 

3

 

 

 

 

 

 

4

 

 

 

 

 

 

 

 

 

 

D302

 

 

 

 

 

 

D304

 

 

 

 

 

 

 

 

 

 

 

 

 

BAS16W SM

 

 

 

Z301

BAS16W SM

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Q305

 

+15V

 

LM317T

 

 

 

 

+5V

 

 

 

 

 

 

 

 

 

 

2SA1964

 

+15V3

I

Vin

 

Vout

O

 

 

+5V

D

SK300

 

 

 

 

 

 

 

 

Q306

 

 

 

ADJ

 

 

 

 

D

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

MOLEXPWR4

 

 

 

 

UR+

 

 

BC846B

 

 

 

 

 

D305

 

R303

 

 

 

 

 

D300

D301

 

+ C300

Q300

 

 

 

 

 

 

A

 

BAS16W SM

470R SM

 

 

 

 

 

S1D

 

S1D

 

J112

 

 

 

 

C304

 

 

+3.75V

 

 

 

 

 

 

 

 

 

 

 

 

1000u 35V

 

 

 

 

 

 

 

 

 

 

 

 

4

3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

F300

 

 

 

 

 

 

 

 

 

100N SM

 

 

 

 

 

 

 

AC1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

R300

 

 

 

+

 

R302

 

 

 

+ C306

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

+

 

 

 

 

 

 

 

 

 

 

 

330R SM

 

D310+

 

C303

 

 

 

1K2 SM

 

 

470U EL 25V

 

 

 

T2A SM

 

 

 

 

 

 

 

 

 

3300u 25V

 

 

 

C305

 

 

 

 

2

1

 

C307

C308

 

 

 

 

 

D310

 

 

 

 

R307

10U EL

 

 

 

 

 

 

 

470N PE

100N SM

 

 

 

 

 

15V 350MW SM

 

 

 

 

 

 

 

 

 

 

 

 

 

 

C314

 

+ C302

 

 

 

 

220R SM

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1N0 PP

220U EL

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

C309

 

 

 

 

+ C312

 

 

 

 

 

 

 

+15V

SK301

 

 

 

 

 

 

 

 

C315

 

 

 

 

 

 

 

 

 

1

 

 

 

 

F301

 

100N SM

 

 

 

220U EL

D311

 

 

 

 

 

 

 

2

 

C

 

 

AC2

 

 

1N0 PP

 

 

 

 

 

 

 

C

 

 

 

 

 

 

 

 

15V 350MW SM

 

 

 

0V_PSU

 

 

3

 

 

 

 

 

 

 

 

 

 

 

 

+ C313

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

-15V

 

4

 

 

 

 

T2A SM

 

 

 

 

 

 

 

 

 

3300u 25V

 

 

 

0V_PSU

IDC4S

 

 

 

 

 

 

 

 

 

 

Q303

 

D311-

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

J112

 

 

 

 

 

 

 

0V_MODULE

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

D306

D307

 

+ C310

R304

 

 

 

 

 

SP300

 

 

 

 

 

 

 

 

 

S1D

 

S1D

 

1000u 35V

 

 

 

 

 

 

0V_PSU

 

 

 

 

 

 

 

 

 

330R SM

 

 

 

 

 

STAR POINT 4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Q307

 

 

 

 

 

 

0V_SIG

 

 

 

 

 

 

 

 

 

 

UR-

 

 

BC856B

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

-15V3

 

0V_HF

0V_MODULE

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

-15V

 

 

 

 

 

 

 

 

 

 

 

 

 

Q301

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2SC5248

 

 

 

 

 

 

 

0V_SIG

 

 

 

 

 

 

 

 

 

 

 

 

D308

 

 

 

 

 

 

 

 

 

 

B

 

 

 

 

 

 

 

 

BAS16W SM

 

 

 

 

 

 

 

 

 

B

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DRAWING TITLE

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Integrated amplifier preamp - power supply

 

 

 

 

 

 

 

 

 

 

 

 

A

 

 

 

 

 

23425

 

Notes:

Circuit Diagram

 

 

 

 

 

 

 

 

 

A

 

 

 

 

 

 

 

 

 

01_E014

JBR

28/11/01

Fuses uprated to 2A

 

 

 

 

 

 

 

 

A & R Cambridge Ltd.

 

 

 

 

 

 

1.1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Pembroke Avenue

 

 

 

 

 

01_1142

JBR

14/8/01

First production release

 

 

1.0

 

 

 

 

 

 

Denny Industrial Centre

 

 

 

ECO No.

INITIALS

DATE

 

 

DESCRIPTION OF CHANGE

 

ISSUE

 

 

 

 

 

 

Waterbeach

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Filename

 

 

 

Date Printed

 

 

Drawn by:

 

 

 

 

 

 

 

 

 

 

 

Cambridge CB5 9PB

 

 

 

 

 

Sheet 3 of 3

DRAWING NO.

L937C3

 

 

 

 

 

 

J:\Change_Control\ECO_AGENDA\01_E014 Fuse changes on A32 preamp\L937_1.1.ddb - Documents\Schematic\L937C328-Nov-2001_1.0.SCHJBR

 

 

 

 

1

 

 

 

 

2

 

 

 

 

3

 

 

 

 

 

 

4

 

Image 17
Contents A85 Contents List Pre-amplifier circuit description Amplifier & PSU Circuit Description L882 Circuit Sheet PSU Ground naming convention is as follows A85, P85, P85/3 Service Guide Fault Diagnostics A85 amplifier and PSU top sheet Circuit Diagram A85 amplifier power supply and microcontroller interface A85 amplifier power output stage left A85 amplifier power output stage right DVD Display PCB USE Exclude NF When Using Runout Sheet Program Integrated amplifier preamp main signal path Integrated amplifier preamp power supply A85 Display PCB Circuit Diagram A85 Phono Stage TOP Level A85 Phono Stage Left Channel A85 Phono Stage Right Channel AP85 third channel top level 23425 P85 microcontroller and switch Page Page Page Page Page Page Page Arcam 220NF Class X2 CAP 275VRMS IC Vreg POS Wima FKP2 Ppro Obsolete, absent, redundant, or incorrect issue in PDM Part Qty Iss Description Designators Phono SKT 4-WAY EMC Gold SK2 SK3 SK4 SK5 WAF MN12818A VFD Itron DISP1 Title A85 Phono PCB Title RES SM Phono SKT 2-WAY EMC Gold Title P85 Switch Board Tact Switch 2-PIN LOW Prof SW1 SW2 A85 General Assembly Parts List Silver Black Description Where Used QTY P85 General Assembly A85P Transformer P85/3 General Assembly Clamp E912MC to E804HK ST=L
Related manuals
Manual 14 pages 30.61 Kb

A85 specifications

The Arcam P85 and A85 amplifiers are a testament to Arcam's commitment to high-quality audio performance. These components are well-known in the audiophile community for their unique blend of state-of-the-art technology and superior sound quality, catering to discerning listeners who value fidelity and craftsmanship.

The Arcam A85 is a high-performance integrated amplifier that features a robust design and advanced circuitry. It offers a powerful 85 watts per channel output, which is more than sufficient to drive a wide range of speakers with clarity and precision. The A85 incorporates a dual mono design with separate power supplies for the left and right channels, ensuring low crosstalk and high channel separation. This design choice also enhances the amplifier’s dynamic response, allowing it to handle complex musical passages with ease.

One of the standout features of the A85 is its use of high-quality components, including low-noise transistors and capacitors that are specifically chosen to minimize distortion. The amplifier exhibits an impressive signal-to-noise ratio, contributing to a clean audio signal that preserves the nuances of the music.

On the other hand, the Arcam P85 is a powerful, dedicated power amplifier that pairs perfectly with the A85. It utilizes a Class G amplification technology, which provides significant power efficiency. This means that the P85 can deliver peak power output without generating excessive heat, making it an ideal choice for long listening sessions.

The P85 offers 85 watts per channel into 8 ohms but can also deliver 140 watts into 4 ohms, allowing it to drive even the most demanding loudspeakers with authority. Its balanced XLR inputs, alongside standard RCA inputs, ensure compatibility with various audio sources, while the sturdy construction ensures durability and performance.

Both the A85 and P85 feature a simple yet elegant design, characterized by a sleek chassis that minimizes resonances and maximizes aesthetic appeal. They also come equipped with a variety of connection options, including multiple line-level inputs and outputs, making integration into an existing audio system straightforward.

In summary, the Arcam P85 and A85 amplifiers represent a harmonious fusion of innovative technology, impeccable sound quality, and user-friendly design. Their powerful performance, combined with high efficiency and low distortion, makes them a prized possession for any audiophile seeking to enhance their listening experience. Whether used in a stereo setup or as part of a more extensive home theater system, the A85 and P85 deliver exceptional audio performance that stands the test of time.