wired to the low (cold) and the ground (earth) connections of the balanced input. If there are ground-loop problems, try disconnecting the unbalanced ground (earth) connection from the balanced input ground (earth) connection, leaving the unbalanced ground connected to the balanced input low (cold) connection only.

In some cases, you may have to make up special adapters to interconnect your equipment. For example, you may need a balanced XLR female connected to an unbalanced 1/4" TS phone plug. Many common adapters can be found at your local electronics supply store.

The balanced-to-unbalanced connection has been anticipated in the wiring of Mackie jacks. A 1/4" TS plug inserted into a 1/4" TRS balanced input, for example, will automatically unbalance the input and make all the right connections. Conversely, a 1/4" TRS plug inserted into a 1/4" unbalanced input will automatically tie the ring (low or cold) to ground (earth).

DB25 Connectors

Not all DB25 connectors are alike. Some provide analog audio signals and some provide digital audio signals. In addition, there are a variety of digital formats that use the DB25 interface, which are not compatible with each other. So when you are connecting the Digital X Bus I/O cards to other equipment, make sure you know what flavor DB25 connectors you have and that they are compatible with each other.

Analog

The inputs and outputs on the Mic/Line 8 card and the Line card provide eight balanced line-level signals per DB25 connector. These connectors are pin-for-pin compatible with the analog (not TDIF) DB25 connectors found on TASCAM DTRS record- ers, which has become an industry standard for many professional audio manufacturers. They are also the same pinout as the analog cards for the Mackie D8B and hard disk recorders.

 

 

CH 1

CH 2

 

CH 3

CH 4

CH 5

 

CH 6

CH 7

 

CH 8

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

GROUND COLD HOT

GROUND COLD HOT GROUND

COLD HOT

GROUND COLD HOT GROUND

COLD HOT

GROUND COLD HOT GROUND

COLD HOT

GROUND COLD HOT

N/C

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

13

 

 

12

 

 

11

 

 

10

 

 

9

 

 

 

8

 

 

 

7

 

 

 

6

 

 

 

5

 

 

 

4

 

 

 

3

 

 

 

2

 

 

 

1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

25 24 23

22 21 20 19 18 17 16 15 14

Analog DB25 Output

Several companies make DB25-to-DB25 cables specifically for audio, with proper shielding to reduce crosstalk and noise.

DB25 cables that break out to XLR, 1/4" TRS, or

TTconnectors for connecting to other mixers or au- dio gear are also readily available. See your Mackie dealer for details.

Digital

AES/EBU

The AES card has a DB25 connector that provides digital I/O for eight channels in the AES/EBU format. This connector is wired as follows:

SHIELD SHIELD

SHIELD SHIELD

NC SHIELD

SHIELD SHIELD

SHIELD CH7/8 OUT–

CH 7/8 OUT+ CH 5/6 OUT– CH 5/6 OUT+ CH 3/4 OUT–

CH 3/4 OUT+ CH 1/2 OUT–

CH 1/2 OUT+ CH 7/8 IN– CH 7/8 IN+ CH 5/6 IN–

CH 5/6 IN+ CH 3/4 IN–

CH 3/4 IN+ CH 1/2 IN– CH 1/2 IN+

13

 

 

12

 

 

11

 

 

10

 

 

9

 

 

8

 

 

7

 

 

6

 

 

5

 

 

4

 

 

3

 

 

2

 

1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

25 24 23 22 21 20 19 18 17 16 15 14

Digital DB25 AES/EBU Output

Note: A variety of alternate pin-out configurations have been developed by various manufacturers for the AES/EBU DB25 interface. Make sure the device you are connecting to has the same pin-out configu- ration as the Digital X Bus AES card. If not, you will need to make a conversion cable so the signals arrive at the correct pins on the receiving end of the cable.

TDIF

The DIGI card has a DB25 connector that provides digital I/O for eight channels in the TDIF format. This connector is wired as follows:

DIN 1/2 DGND

DIN 3/4 DGND

DIN 5/6 DGND

DIN 7/8 DGND

LRCK IN EMPH IN

FS1 IN FS0 IN DGND FS1 OUT

FS0 OUT EMPH OUT

LRCK OUT DGND DOUT 7/8 DGND

DOUT 5/6 DGND

DOUT 3/4 DGND DOUT 1/2

13

 

 

12

 

 

11

 

 

10

 

 

9

 

 

8

 

 

7

 

 

6

 

 

5

 

 

4

 

 

3

 

 

2

 

1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

25 24 23 22 21 20 19 18 17 16 15 14

Digital DB25 TDIF Input/Output

Manual Owner's

Owner's Manual

79