AVM EVOLUTION CD2 Operating Instructions Manual

AV

M Evolution

C02

96kHz'

24

btt

BETRIEBSANLEITUNG

CD-PLAYER

EVOLUTION

C02

OPERATING

INSTRUCTIONS

CD-PLAYER

EVOLUTION

C02

DEAR

AVM

CUSTOMER,

thank you for

the

trust

you have showninus

with

the

purchase of this Evolution

CD2

unit.

You

have acqui-

red a versatile

hi-fi

component

with absolutely excellent sound qualities.

It

is

understandable

that

you would

liketoimmediately

start

listeningtothe

music. Despite this we advise

you

to

show

some

patience; you

will

find

that

this

will

stand youingood

stead.

Before you take this equipment into use for

the

first time you should thoroughly read this operating manu-

al.Itwill

ensure

that

the

equipment can be optimally usedtogive you a

great

dealofuntroubled pleasure.

We

have made every efforttoincludeinthis manual

all

the

necessary information for providing assistance

to

operate

the

equipment. Please

contactusin

writingorby

telephoneifyou have further questions,ifthe

answers are

nottobe found here.Wewill

make every efforttoprovide you with assistance.

TEAM

CAUTION:

This unit contains a class I laser diode.

Never

open

the

casingorremove any covers

otherwise

invisible laser

light could cause damage

to

the

eyes.AII maintenance should be carried

outbyqualified service personnel.

ews

I

WER

PRooua

Laser diode

Type
Wavelength
Laser

performance

Ga-AI-As
755 -

815

nm

(25°C)

max.0.7mW

(continuous rating)

CERTIFICATEOFCONFORMITY

We

confirm

that

the

equipment describedinthese

operating instructions conformstothe

EU

regulations

applicable

at

the

timeofprint permitting ittobear

the

sign (

E:

All

relevant

tests

achieved positive results.

TIPS:

To

produce

the

connections

between

individual unitsofyourhifi

equipment and

the

CD2

only use

high

qua-

lity digital cabling

not

exceeding 50 cminlength. Near-by placed radiosortelevisions can

otherwise

suffer

reception interference.

If

optical cableisused as a digital connection

the

length of

the

cableisnot

critical.

20

THE

CONCEPTOFTHE

EVOLUTION

CD2

The

C02

has been optimizedtoa

sure

and extremely jitter free read

outofthe

digital information

where-

by

the

quantityofinformationisunmistakably definedbythe

CD

format16Bitl44.1 kHzatthe

converter

input.Additional informationinthe

senseofa higher resolutionoran

extended

frequency rangeisnot

achie-

vable. Most

of

the

currently used digitallanalogue (D/A)

converters

are

not

abletocompletely

convert

the

information offered on

the

CDtoanalogue signals for

the

following reasons.

A n

in

built problem with systems when reconverting digital informationisthe

so-called quantization noise.

This results from slight inaccuracies displayed

by

the

discrete existing valuesincomparisontothe

original

analogue signal.

With

the

CD

format

these

inaccuracies are definedbythe16Bit

word

breadth,inother

words

that

during

the

productionofthe

CDapendant

with a maximum resolutionof65,536 stagesisatta-

ched

to

the

analogue signal.Ifan analogue signal lies between

these

stages a principle

error

occurs

during

recording which limits

the

achievable tonal quality.

The

recordingistherefore

produced with a far

greater

resolution than can actually be

storedonthe

CDinan

attempttominimize

the

error.

The

remaining inaccuracies are randomly distributed and

become

apparent during re-conversionasan

even-

ly

distributed noise

over

the

useful frequency band.This noise limits

the

dynamic characteristics approaching

the

lower ranges and ieadstoconcealment of

the

fine information held on

the

CD.Ifthe

digital signal

is

upsampledtoa higher frequency

priortore-conversion

the

quantization noiseisdistributed

overagreater

frequency spectrum. However because

the

noise energy remains

constant

the

greater

noise band width leads

to

a lower noise level. A large

partofthe

noiseisnow situated outside

the

relative audio frequency band

and can be filtered

out

relatively easily.This

does

not

mean

that

new informationisgained

however

that

part

of

the

information

that

was previously coveredbythe

noise becomes audible.

For this reason

the

digital signal of

the

C02isupsampledto24 Bitl96 kHz

priortothe

DIA conversion.

The

enlargementofthe

word

breadthto24 Bit leadstoa clear reductionofthe

quantization noiseofthe

DIA

converter.

At

the

endofthe

frequency range

the

low frequency signals must be filteredtoseparate

aliasing

compo-

nents from

the

useful signal. The filtration causes drastic phase shifts

under

normal circumstances which can

be detrimental

to

the

spatial image.Aliasing

components

become

apparent from a frequency

of22kHz with

standard

CD

format.This makes

the

employmentofsteep sloop analogue filtersofa

high

order

necessary

which lead

toanincreaseofthe

phase- and amplitude distortions.Incomparison upsamplingto96 kHz

aliasing

components

first

become

apparent

beyond 48 kHz.This means

that

impulse optimized filters can

be

utilized which

treat

the

analogue signal with

great

care

within

the

audible range. Phase- and amplitude

distortions

do

not

occur

and

the

tonal image remains correctly pitched and stable.

Special attention was paid

to

the

minimizationofjitter. Deviationinthe

pulse

rateofthe

digital signal

is

knownasjitter.These deviations, which are for

the

most

part

causedbythe drive, resultsinthe

offered infor-

mation being processed

at

the

wrong

moment

of time.This causes distortion and noiseinthe

analogue range

thatintheir

turn are responsible for faded and slightly roughened tonal characteristics.

There

are many ways of ensuring

that

the

offered informationisprocessedinits

exact

chronological

sequence.

AVM

has decidedtoproceed

along a radical and uncompromising path.

Allofthe

clock pulse

frequencies

that

are necessary for signal processing are

generatedina special module

thatisnot

timedbya

normal quartz crystal but instead

byahigh

precision

quartz

oscillator. It can be assured through this

that

the

21

relativity of the needed frequencies always remains exactly equal and therefore

all

assemblies are optimally
synchronized.
By

the

use of upsampling the stream of informationisindependent of the

44.1

kHz clock pulse. Intermediate

storage

in

a buffer followedbyits chronologically

correct

output ensures

that

the converterisnot

affected

by

drive induced jitter.

The front of the

C02isclearly defined and contains

all

of the operating elements necessary for the basic

functions.This permits clarity and simplicity of operation.

Of

course the

C02

can do much more:Title pro-

gramming and special functions, such as the ability

to

switch the digital filter, are available through the remo-

te

control.

MECHANICAL

CONSTRUCTION

The modules, power supply, drive controller,

output

stages are situated on separateICboards.This reduces

mutual influence

to

a minimum. The casing of the

C02ismanufactured from magnetically protecting steel

plate.

The

built-in power transformers are of the low-scatter toroidal type.

The

output

sockets of the

C02

have

surface treated contact areastopromote good contact and durability.

Epoxy resin circuit boards and the use of selected brand named,

high

quality components ensure

that

you

will

have a lot of enjoyment from your

AVM

C02.

THE

POWER

SUPPLY

In

the

same

way

that we believe

that

separation of the drive and the

O/A

converter providesanoptimal

tonal solution due

to

the absolute freedom from reaction itisalso

our

opinion

that

the individual modules

of a CO player should

not

mutually influence each other. For the reason

the

C02

has

two

power supplies

that

are

fed

from low impedance toroidal transformers.

Oneismainly for

the

supply of

the

servo electro-

nics

or

alternatively the audio digital section whereas the

other

delivers currenttothe

O/A

converter and

output

stages

THE

DIGITAl

SECTION

The

output

signals of

the

drive are receivedbythe sampling rate converterCS8420.This increases

the

pulse

rate of the data bits from

16

Bit/44.1 kHzto24 Bit/96 kHzoralternatively 24 Bit/88.2 kHz.This integrated

circuit removes any existing jitter completely from the

signal

(uptothe physically unavoidable minimum)

before it passes it

to

the

digital

filter.

The

digital

filter situated behind

the

sampling rate converter ensures that unwanted frequency components

(aliasing) are removed from the signal

flow.

For this purpose two filter variations are available.Inthe selec-

tion "sharp" the

signal

amplitude

falls

steeply at the end of the transmission range whereas

the

selection

"slow" causes a flatter

fall

off of the amplitude towards the cut-off region.With both variants the complete

audio bandwidth

is

retained so that you can adjust

the

tonal qualities of

the

C02toyour listening prefe-

rences.

22

Besides this

the

digital filter increases

the

sampling frequencybya factorof8 (oversampling) through

extre-

mely fast calculation of intermediate values,

thereby

permitting

the

analogue filter at

the

converter

output

tobelaid

outinas

considerate a

manneraspossible with regardtophase and amplitude.

All

necessary pulse frequencies are

producedbya mutual,

extremely

precise pulse generator.

The

audio digital informationisavailableinCD

standard

format

(16

Bit!

44.1 kHz)oneachofthe

three

dig-

ital

outputs.

THE

DIGITAl/ANALOGUE

(D/A)

CONVERTER

The

raw data from

the

digital filtersispassed discretely through

separate

channelstothe

D/A

converters.Weinstall only pre-selected Burr-Brown

PCM

1704 converters.This

high

precision parallel con-

verterisconsideredtobe

the

best

product

availableonthe

market. Strict selection

procedures

and careful

laser trimming of

the

converterbythe

manufacturer

ensures

constant

high

tonal qualityofthe

CD2.

THE

ANALOGUE·FILTER

Filtering

the

signals after conversion

ensures

that

unwanted frequency remnants (aliasing, sampling frequen-

cy)

are

removed from

the

converted

audio signal.

We

regard filteringtobe very important.

The

wayinwhich

filters

work

with phase and amplitudeofthe

signals can have serious effectsonthe

tonal qualityofa D/A

converter.

We

have

created

a filter

that

causes no ampiitudeorphase

errors

within

the

audio frequency

range.This was possible because upsampling means

that

aliasing

components

are

onlytobe

expected

after

half

of

the

sampling frequency has been reached ie. initially after48kHzor44.1 kHz.Byemploying 8 x over-

sampling

in

the

digital filter

these

limits

are

displaced even

further

upwards.

THE

ANALOGUE

OUTPUTS

The

CinchorXLR

analogue

outputsofthe

CD2

possess

two

discretely

constructed

power

amplifiers.

Their

great abilitytoprovide a

current

supply coupled with

their

low

output

resistance

ensures

precise transmiss-

sion of

the

musical signalstothe

pre

amplifier.The phase positionofthe

output

signal can be

rotated

through

180 degrees

via

the

remote

control.

23

In

the

text

you

will

find numbers behind

the

descriptionsofthe

individual operating elements.

These

relate

to

the

following diagrams.

It!

lit

',"n

t1ll1TllIlIllIlI'

~

IttU11"1111'

'flllll

IIlrU'

•

rlUUlllrtu

0

0

0

,0

0 0

I

~,

0

11111

,0

~,-

'''''''1'' ""

liltn.lOll

((

11"-1111

AV'A

[

J

0"'"'

·(ll

~

~

IlPl"

rill

[

I

HIl

'UI

'''11

Ill/

III'UIIII

0

0 0

0

0

0 0 0 0

0

20

9

10

II

12

13

19

18

18

XLR analogue

output

right

19

XLR analogue

output

left

20

Power

supply

socket

8

17

7

16

15

2 3 4 5 6

14

14

Optical digital

output

15

Cinch digital

output

16

XLR

digital

output

17

Cinch analogue

output

THE

OPERATIONOFTHE

EVOLUTION

CD2

I

Operation

control

LED

2

On/Off

switch

3 Title select

button

and continual reverse search
4 Title select button and continual forward search
5

REPEAT

button

6 Button for alterationofthe

TIME

display
7 Display window
8

CD

tray

9 Button for opening and closing

the

CD

tray - OPEN

10

Buttontocommencementofthe

play

procedure-PLAY

I 1 Button for activation Ideactivationofthe

PAUSE

function

12

Buttontoend

the

play

procedure

and deletionofprogramming - STOP

13

Buttontoswitch off

the

display -

DISPLAY

OFF

24