Digital audio adda 2402 User Manual

ADDA 2402

User manual

IMPORTANT SAFETY AND INSTALLATION INSTRUCTION

SAVE THESE INSTRUCTIONS

INSTRUCTIONS PERTAINING TO RISK OF FIRE, ELECTRIC SHOCK, OR INJURY TO PERSONS

WARNING – when using electric products, basic precautions should be followed, including the following:

1. Read all of the safety and installations instructions and explanation of graphic symbols before using the product.

2. The product must be grounded. If it should malfunction or breakdown, grounding provides a path of least resistance or
electric current to reduce the risk of electric chock. This product is equipped with a power supply cord having an equipment­grounding conductor and a grounding plug. The plug must be plugged into an appropriate outlet which is properly installed
and grounded in accordance with all local codes and ordinances.

DANGER – Improper connection of the equipment-grounding can result in a risk of electric shock. Do not modify the plug
provided with the product – if it will not fit the outlet have a proper outlet installed by a qualified electrician. Do not use an
adapter which defeats the function of the equipment-grounding conductor . If you are in doubt as to whether the product is
properly grounded, check with a qualified serviceman or electrician.

3. Do not use this product near water – for example, near a bathtub, washbowl, kitchen sink, in a wet basement, or near a
swimming pool, or the like.

4. This product should only be used with a stand or cart that is recommended by the manufacture.

5. This product, either alone or in combination with an amplifier and speakers or headphones, may be capable of producing
sound levels that could cause permanent hearing loss. Do not operate at a high volume level or at a level that is uncomfortable.
If you experience any hearing loss or ringing in the ears, you should consult an audiologist.

6. The product should be located so that its location or position does not interfere with its proper ventilation.

7. The product should be located away from heat sources such as radiators, heat registers, or other products that produce heat.

8. The product should be connected to a power supply only of the type described in the operating instructions or as marked on
the product.

9. The power-supply cord of the product should be unplugged from the outlet when left unused for a long period of time.
When unplugging the power supply, do not pull on the cord, but grasp it by the plug.

10. Care should be taken so that objects do not fall and liquids are not spilled into the enclosure through openings.

11. The product should be serviced by qualified service personnel when:
A. The power supply cord or plug has been damaged, or
B. Objects have fallen, or liquid has spilled into the product, or
C. The product has been exposed to rain, or
D. The product does not appear to be operating normally or exhibits a marked change in preformance, or
E. The product has been dropped, or the enclosure damaged.

12. Do not attempt to service the product beyond that described in the user maintenance instructions. All other servicing

should be referred to qualified service personnel.

13. WARNING - Do not place objects on the power supply cord, or place the product in a position where anyone could trip over ,

walk on, or roll anything over cords of any type. Do not allow the product to rest on or be installed over cords of any type.
Improper installations of this type create the possibility of a fire hazard and/or personal injury.

ATTENTION

: RISQUE DE CHOCK ELECTRIQUE NE PAS OUVRIR

CAUTION

RISK OF ELECTRIC SHOCK

DO NOT OPEN

CAUTION: TO REDUCE THE RISK OF ELECTRIC SHOCK

DO NOT REMOVE COVER (OR BACK).

NO USER-SERVICEABLE PARTS INSIDE.

REFER SERVICING TO QUALIFIED SERVICE PERSONNEL.

The lightning flash with arrowhead symbol,
within an equilateral triangle, is intended to
alert the user to the presence of uninsulated
"dangerous voltage" within the product's
enclosure that may be of sufficient magnitude
to constitute a risk of electric shock to persons.

The exclamation point within an equilateral
triangle is intended to alert the user to the
presence of important operating and
maintenance (servicing) instructions in the
literature accompanying the product.

© 1999 All rights reserved. Digital Audio Denmark and ADDA 2402 are registered
Trademarks of Digital Audio Denmark a/s.

Product features and specifications are subject to change without notice .

Digital Audio Denmark a/s shall not be liable for technical or editorial errors contained herein,
nor for incidental or consequential damages resulting from the furnishing, performance or use
of this manual.

Company Address: Digital Audio Denmark. PO Box 141. DK 2630 Taastrup.
Fax. [phone]. E-mail: [e-mail] www.digitalaudio.dk

No. 973000020 rev. 1

Contents

5

1. INTRODUCTION 7

WELCOME 7
OVERVIEW OF ADDA 2402 7

2. INSTALLING THE ADDA 2402 9

BEFORE YOU START 9
INSTALLATION 9

Connecting the Power Cable 9
Connecting the analog audio cabels 10
Connecting the digital audio cables 10
Connecting the digital sync input 10

USE THE ADDA 2402 AS A SMALL ANALOG/DIGITAL CROSS-FIELD 10

3. OPERATION 11

FRONT PANEL CONTROLS 11

Analog Input 11
Digital Input 11
Digital Output Source 11
Sample Rate 12
Dither 12
Sync. 12
Power 12

THE PEAK METER 12

4. BLOCK DIAGRAM 13

5. SPECIFICATIONS 15

ANALOG-TO-DIGITAL CONVERSION 15
DIGITAL-TO-ANALOG CONVERSION 17
DIGITAL-TO-DIGITAL CONVERSION 19
GENEREL 21

6. References 23

7. Appendix, Distortion Effects from Aliasing in Digital Audio 25

6

1. Introduction

Welcome

Congratulations, and thank you for purchasing the Digital Audio Denmark ADDA2402 audio
converter. You have in your possession an extremely capable audio converter, which enables
you to perform high-end analog-to-digital, digital-to-analog and digital-to-digital conversion
of audio signals.

Overview of ADDA 2402

The ADDA2402 is a full duplex converter, which can perform independent simultaneous
analog-to-digital (A/D), and digital-to-analog (D/A) conversion between analog audio signals
and AES/EBU or S/PDIF digital audio signals. The digital interfaces comply to AES31.

The A/D converter converts an analog audio signal to a high quality digital signal with a
sample-rate of 32 kHz, 44,1 kHz 48 kHz, 64 kHz, 88,2 kHz or 96 kHz, a noise floor below
117 dB(A)2 at 44,1 Khz sampling, and a THD+N below 107 dB at 6 dBu input level.
The input level can be monitored on the Peak Programme Meter (PPM) at the front, and the
input can be selected to be either the XLR connectors or Jack connectors.
The A/D conversion is 24 bit. Depending on the conversion application the A/D converter
resolution can be reduced to 20 bit, 18 bit or 16 bit by adding psycho acoustic dither 3 to the
signal.
The bandwidth of the converted signal is equal to half the sample-rate, giving a bandwidth
from 16 to 48 kHz. The filters in the A/D converter assure that no signal is present above half
the sample-rate. This means that no aliasing distortion is introduced in the A/D converter.
Having no alias components in the digital signal eliminates the risk of generation of Alias
Intermodulation Distortion (AID)4.

The D/A converter converts a digital audio signal to a high quality analog signal having a
dynamic range better than 117 dB(A) at 44,1 Khz sampling, and a THD+N below 90 dB at
6 dBu output level.
You can chose between three digital input sources, either a professional AES/EBU signal on
XLR connectors, a consumer S/PDIF signal on Phone connectors or an optical S/PDIF signal
on a TosLink connector.
The D/A converter automatically adapts to the sample-rate of the incoming digital signal
which can be 32 kHz, 44,1 kHz 48 kHz, 64 kHz, 88,2 kHz or 96 kHz.

The ADDA 2402 can also be configured as a digital-to-digital (D/D) converter for sample-rate
conversion (SRC) of a digital input of a given sample-rate and format to a digital output of an
other sample-rate and format.
The converter can do sample-rate conversion between any of the six sample-rates from 32
kHz, 44,1 kHz 48 kHz, 64 kHz, 88,2 kHz to 96 kHz, and convert between the professional
and the consumer AES/EBU format.

ADDA 2402 has high precision internal oscillators with a stability of +/- 5 parts per million
(PPM) controlling the sample-rates. The ADDA2402 can also be synchronised to an external
reference signal complying with AES 115.

1

Please refer to section 5, references for an explanation of AES 3.

Please refer to section 3, The peak meter for a description of the input levels and the dB

notification.

3

Please refer to section 5, references for an explanation of the psycho acoustic dither.

4

Please refer to Appendix 1 for a description of AID.

5

Please refer to section 5, references for an explanation of AES 11.

7

8

SP/DIF

OPTICAL

SP/DIF

OPTICAL

Digital out

Analog in

L

R

AES/EBU

AES/EBU

Digital in

Analog outLR

Ext. sync

L
R

L
R

AC POWER

CONNECTOR

MAIN POWER

SWITCH

FUSE

HOLDER

EXT. SYNC

AES/EBU INPUT

OPTICAL S/P DIF

OUTPUT

S/P DIF

OUTPUT

AES/EBU
OUTPUT

OPTICAL S/P DIF

INPUT

S/P DIF

INPUT

AES/EBU

INPUT

BALANCED

ANALOG OUTPUT

SINGEL ENDET

ANALOG OUTPUT

BALANCED

ANALOG INPUT

SINGEL ENDET

ANALOG INPUT

1. Installing the ADDA 2402

Here is a quick description of all the basic things you need to cover to get started with your
ADDA 2402.

Before Y ou start

· Make sure the ADDA 2402’s voltage matches the voltage in your location. The ADDA
2402 is labelled on the AC power connector with the main voltage setting which can be
either 110-120V, 220-240V or 110-240 V at 50-60 Hz.

· Set your ADDA 2402 on a hard and dry surface or mount it onto a 19” rack, and leave
plenty of room for ventilation.

· In order to meet the EMC requirements of Directives 89/336/EEC and 93/68/EEC, and in
order the obtain the high performance possible for the ADDA 2402, you must use
correctly shielded cable of good quality for all external connections, when installing the
ADDA 2402. For the power connection a normal un-shielded cable can be used. Make
sure that the XLR, Phono and Jack connectors have conductive houses connected the
shield.

· Make sure your sound system is at a safe volume level.

Installation

This section will take you through the installation of your ADDA 2402. We will describe the
power, audio and digital cable connections, which can be accessed on the rear panel.

Connecting the Power Cable

The ADDA 2402 runs on 50-60 Hz AC voltage, and is set from the factory to, 110-120 V, 220

-240 V or 110-240 V. Excessive voltages can seriously damage the ADDA 2402, so make sure

that your AC power matches the setting of your ADDA 2402.
When you connect the power use the cable you received together with your ADDA 2402 and
plug it into a grounded outlet.
If your power source does not have the standard three-hole outlet, you should take the time to
get installed a proper grounding system. This will prevent problems with audio hum, and will
reduce the risk of a shock hazard. Furthermore it is required that the converter is grounded in
order to fullfill both the safety requirements and the EMC requirements.

9