ADC8 Mk IV

DAC8 Mk IV

USER MANUAL V1.3

A/D Converter ADC8 Mk IV

The EMM Labs 8-channel A/D converter is a 4th generation design to meet the highest standards in professional audio recording applications. It offers conversion between analog and digital audio of various different formats, as well as conversion between digital audio formats.

Features

• 8-channel conversions:

• from analog to PCM (16/24 bits selectable and 44.1kHz - 96kHz)

• from analog to DSD

• from DSD to PCM (44.1kHz - 16/24 bits selectable)

• from DSD on optical to DSD on BNC connectors

• from DSD on BNC to DSD on optical connectors

• Supported output formats:

• AES/EBU (4 connectors) for PCM

• “RAW DSD” (legacy format for DSD on BNC conectors)

• SDIF-3 for DSD on BNC connectors

• SDIF-2 for PCM on BNC connectors

• ST Fiber optic for DSD

• Supported input formats:

• Balanced analog 8dbu - 32dbu (pin 2 hot), switchable ranges 8dbu-20dbu /

20dbu - 32 dbu.

• “RAW DSD” (legacy format for DSD on BNC conectors)

• SDIF-3 for DSD on BNC connectors

• ST Fiber optic for DSD

• Power supply

• power factor corrected

• auto ranging 85V - 240V, 50/60Hz

• power consumption: 60W

• Analog input impedances

• in HI gain position: 30k

Ω balanced, 15kΩ unbalanced

• in LO gain position: 68k

Ω balanced, 34kΩ unbalanced

1

Signal flow

DSD (Optical)

DSD (RAW/SDIF3)

(shared Conn.)

Analog

DSD

DSD to PCM

Conversion

A/D

Conversion

DSD

DC Removal

PCM

(AES/EBU)

PCM

(SDIF2)

DSD

(optical)

DSD

(shared Conn.)

Note: Analog inputs are balanced with pin 2 hot, pin 3 cold and pin 1 GND. For unbalanced inputs just connect to pin 2 and tie pin 3 to GND.

Function Switches

Note: Some configurations require long settling times of up to several seconds after changing switch positions.

Note: The powerup sequence and initial calibration of the unit takes about 20 seconds after power is applied.

Clock Section

INT /EXT:

OPTIC / BNC:

Sample Rate Section

64 / 128:

1FS / 2FS:

44.1 / 48:

Selects internal or external clock source. LOCK LED is lit when A/D converter is locked to external clock.

Selects external clock between optical and BNC formats.

Selects oversampling ratio. 128 position does not allow

2FS PCM generation (error light on).

Selects the sample rate for PCM data. FS is the base frequency (see 44.1 / 48 switch). 2FS position will mute outputs when the oversampling ratio is set to 128.

Selects the base frequency (only 44.1kHz is allowed for

DSD outputs and inputs).

2

3

Digital Audio Input Section

OUT / IN:

OPTIC / BNC:

OUT position selects conversion from analog to digital.

IN position selects conversion from digital to digital.

If the DATA DIR switch is set to IN, this selects data input between optical or BNC connectors (data format is selected in Interface Format Section).

Interface Format Section

RAW / SDIF-3:

DSD / PCM:

When DSD is on BNC the user has the choice between

RAW and SDIF-3 formats.

This switch selects DSD or PCM format on the BNC connectors (in both directions).

OPTIC1 / OPTIC2: Selects format 1or 2 for both input and output (currently not implemented - only 1 format).

16 / 24 BITS: The wordlength of the PCM outputs can be selected between 16 and 24 bits. The 16 bit position uses noise shaping to convert original format of 24 bits to 16 bits.

Error Indicator is lit for illegal switch positions (audio outputs are muted)

Analog Input Level

LO / HI: The LO position allows the user to set levels between

+20dbu and +32dbu.

The HI position allows the user to set the levels between

+8dbu and +20dbu.

Clipping indicators

The clipping LED’s come on when the level on the PCM outputs reach

0dbFS. This level corresponds to 0dbSACD on all DSD outputs. However, the levels on the DSD outputs are allowed to go up to +3dbSACD.

4

Conversion

Analog to

DSD, PCM

Analog to

DSD, PCM

DSD to DSD,

PCM

DSD to DSD,

PCM

BNC

DSD Out

PCM Out

(SDIF-2)

DSD In

DSD Out or

PCM Out

Table 1:

Functional Modes of A/D

Analog In

In

AES/EBU

PCM Out

Optical In

-

Optical Out

DSD Out

In

-

-

PCM Out

PCM Out

PCM Out

-

-

DSD In

DSD Out

DSD Out

DSD Out

Basic Operation

In addition to the basic conversion modes shown below, the ADC8 Mk IV converts between DSD on optical and DSD on BNC (RAW DSD or SDIF-3) and back again.

Conversion from Analog to DSD and PCM

INT

CLOCK

OPTIC

64

SAMPLE RATE

1 FS

44.1

DIGITAL AUDIO IN

OUT OPTIC RAW DSD

INTERFACE FORMAT

DSD

16 BIT

EXT LOCK

EXTERNAL

BNC 128

OVERS.

2 FS

PCM

48

BASE

“Empty” switches are ignored.

IN

DATA-DIR

BNC SDIF-3

BNC

PCM 2

OPTIC

24 BIT

PCM OUT

Note: DSD and PCM is only generated simultaneously when the base frequency 44.1kHz and

1FS are selected.

Note: The PCM sample rate of 2FS can only be selected for the oversampling ratio of 64FS

Optional selections:

• Oversampling ratio 64FS / 128FS: this changes the bit rate of the DSD output. No optical DSD output is generated for 128FS. When 128FS is selected DSD is generated at 128FS in either RAW DSD or SDIF-3 format.

• Wordlength of PCMOUT 16bit / 24 bit

• The PCM data can also be routed to the BNC outputs (SDIF-2 format) with the DSD / PCM switch.

5

• DSD format on BNC connectors RAW DSD / SDIF-3

Conversion from DSD to PCM

INT

CLOCK

OPTIC 64

SAMPLE RATE

1 FS 44.1

DIGITAL AUDIO IN

OUT OPTIC RAW DSD

INTERFACE FORMAT

DSD 16 BIT

EXT LOCK

EXTERNAL

BNC 128

OVERS.

2 FS

PCM

48

BASE

IN

DATA-DIR

BNC SDIF-3

BNC

PCM 2

OPTIC

24 BIT

PCM OUT

“Empty” switch positions are ignored.

DSD input can be on BNC or optical connectors. Appropriate selections have to be made in the CLOCK and DIGITAL AUDIO IN sections (OPTIC / BNC).

DSD data rate at input can be either 64FS or 128FS as selected by

Oversampling ratio.

Note: 2FS PCM generation is only possible from 64FS DSD and not from 128FS.

Optional selections:

• Wordlength of PCMOUT 16bit / 24 bit

• The PCM data can also be routed to the BNC outputs (SDIF-2 format) with the DSD / PCM switch, in case the DSD input is optical.

6

D/A Converter DAC8 Mk IV

The EMM Labs 8-channel D/A converter is a 4th generation design to meet the highest standards in professional audio recording applications. It offers conversion between digital audio of various different formats and analog, as well as conversion between digital audio formats.

Features

• 8-channel conversions:

• from PCM (44.1kHz - 96kHz) to analog

• from DSD to analog

• from PCM (44.1kHz, 88.2kHz) to DSD

• from DSD on optical to DSD on BNC connectors

• from DSD on BNC to DSD on optical connectors

• from PCM on AES/EBU to PCM (SDIF-2)

• Supported input formats:

• AES/EBU (4 connectors) for PCM

• “RAW DSD” (legacy format for DSD on BNC conectors)

• SDIF-3 for DSD on BNC connectors

• SDIF-2 for PCM on BNC connectors

• ST Fiber optic for DSD

• Supported output formats:

• Balanced analog 14dbu - 24dbu (pin 2 hot)

• “RAW DSD” (legacy format for DSD on BNC conectors)

• SDIF-3 for DSD on BNC connectors

• SDIF-2 for PCM on BNC connectors

• Power supply

• power factor corrected

• auto ranging 85V - 240V, 50/60Hz

• power consumption: 60W

• Analog output impedances

• 100

Ω balanced, 50Ω unbalanced

7

Signal Flow

DSD (RAW / SDIF3)

(shared Conn.)

DSD (Optical)

PCM (AES/EBU)

PCM* (SDIF2)

(shared Conn.)

DSD

PCM to DSD

Conversion

PCM

Optical

RAW DSD / SDIF3

(shared Conn.)

D/A

(shared Conn.)

DSD

DSD

Analog

PCM

Note: *SDIF2 inputs expect 24-bits (or 0-filled 16 bits) of PCM

Note: Analog outputs are balanced with pin 2 hot, pin 3 cold and pin 1 GND. For unbalanced outputs just connect to pin 2 and leave pin 3 open ended

Function Switches

Clock Section

INT / EXT: Selects internal or external clock source. LOCK LED is lit when D/A converter is locked to external clock.

Sample Rate Section

1FS / 2FS:

44.1 / 48:

Selects the sample rate for PCM data. FS is the base frequency (see selector switch for base).

Selects the base frequency (only 44.1kHz is allowed for

DSD outputs and inputs)

Digital Audio Input Section

IN / OUT:

DSD / PCM:

Selects the data direction on the BNC connectors. DSD and PCM data can be received or transmitted.

Selects digital audio input format.

8

9

OPTIC / WIRE: Selects the physical connector for input data (optical or

WIRE). For the WIRE selection an additional switch is necessary to define WIRE as either BNCor XLR.

BNC / XLR (WIRE): Selects BNC or XLR as input when OPTIC / WIRE switch is set to WIRE

Interface Format Section

RAW / SDIF-3:

DSD / PCM:

When PCM is on BNC this switch needs to be set to

“RAW DSD” which is equivalent for SDIF-2, when DSD is on BNC this switch selects between RAW DSD and

SDIF-3 formats

Selects format for BNC output for all situations where

PCM is selected as input format to D/A converter. This switch has to be in DSD position when DSD is the selected input format via optical to the D/A and is ignored when BNC DIR is set to IN.

Oversampling Ratio

64FS / 128: For PCM input this switch selects the oversampling ratio and for DSD inputs it selects the sample rate of the DSD input data. It also selects the sample rate of the DSD output on the BNC connectors.

Error Indicator Is lit for illegal switch positions

Conversion

DSD to DSD, analog

PCM to DSD, analog

PCM to DSD, analog

DSD to DSD, analog

BNC

DSD In

PCM In

PCM Out or

DSD Out or

-

DSD Out

Table 2: Functional Modes of D/A

Analog

Out

AES/EBU

-

Optical In

-

Optical Out

DSD

Out DSD

Out

Out

PCM In

-

-

DSD

DSD

DSD

10

Basic Operation

In addition to the basic conversion modes shown below, the DAC8 Mk IV converts between DSD on optical and DSD on BNC (RAW DSD or SDIF-3) and back again.

Conversion from PCM on AES/EBU to Analog

CLOCK

INT

SAMPLE RATE

1 FS

44.1

POWER ERROR LOCK

IN

DIGITAL AUDIO INPUT

DSD OPTIC BNC

EXT 2 FS

PCM

IF FORMAT

RAW DSD DSD

48

BASE

64

OUT

BNC-DIR

PCM

WIRE XLR

WIRE

SDIF-3

BNC

PCM 128

BNC OUT

OVERS

Additional selections for 44.1 / 48 / 88.2 / 96kHz sample rate and for the 64/

128 oversampling ratio can be made with the sample rate and oversampling switches.

“Empty” switch positions are ignored.

11

Conversion from PCM on BNC (SDIF-2) to Analog

CLOCK

INT

SAMPLE RATE

1 FS

44.1

POWER ERROR LOCK

IN

DIGITAL AUDIO INPUT

DSD OPTIC BNC

EXT 2 FS

PCM

IF FORMAT

RAW DSD DSD

48

BASE

64

OUT

BNC-DIR

PCM

WIRE XLR

WIRE

SDIF-3

BNC

PCM 128

BNC OUT

OVERS

Additional selections for 44.1 / 48 / 88.2 / 96kHz sample rate and for the 64/

128 oversampling ratio can be made with the sample rate and oversampling switches.

“Empty” switch positions are ignored.

Conversion from DSD on BNC (RAW DSD or SDIF-3) to Analog

CLOCK

INT

SAMPLE RATE

1 FS

44.1

POWER ERROR LOCK

IN

DIGITAL AUDIO INPUT

DSD OPTIC BNC

EXT 2 FS

PCM

IF FORMAT

RAW DSD DSD

48

BASE

64

OUT

BNC-DIR

PCM

WIRE XLR

WIRE

SDIF-3

BNC

PCM 128

BNC OUT

OVERS

12

Additional selection for RAW DSD or SDIF-3 format for DSD input can be made with the interface format switch. The overampling switch needs to be set to the sample rate (64FS or 128FS) of the DSD input data.

“Empty” switch positions are ignored.

Conversion from DSD on Optical to Analog

CLOCK

INT

SAMPLE RATE

1 FS 44.1

POWER ERROR LOCK

IN

DIGITAL AUDIO INPUT

DSD OPTIC BNC

EXT

2 FS

PCM

IF FORMAT

RAW DSD DSD

48

BASE

64

OUT

BNC-DIR

PCM WIRE XLR

WIRE

SDIF-3

BNC

PCM 128

BNC OUT OVERS

In this mode an additional conversion from DSD on optical input to DSD on

BNC output can be performed. For this the BNC-DIR switch needs to be set to OUT, the IF FORMAT switches to either RAW DSD or SDIF-3 and to DSD.

“Empty” switch positions are ignored.

13

14

Conversion from PCM on AES/EBU to DSD on BNC (RAW DSD or SDIF-2) and Optical

CLOCK

INT

SAMPLE RATE

1 FS

44.1

POWER ERROR LOCK

IN

DIGITAL AUDIO INPUT

DSD OPTIC BNC

EXT 2 FS

PCM

IF FORMAT

RAW DSD DSD

48

BASE

64

OUT

BNC-DIR

PCM

WIRE XLR

WIRE

SDIF-3

BNC

PCM 128

BNC OUT

OVERS

Only 44.1kHz based PCM can be converted to DSD. Additional selections can be made for 1FS / 2FS for PCM input and for RAW DSD / SDIF-3 for

DSD output. No DSD output on optical is possible for 128FS, only for DSD on BNC.

“Empty” switch positions are ignored.