User's Guide ADI-4 DD SyncAlign TM TM SyncCheck Intelligent Clock Control TM TM SteadyClock Hi-Precision 24 Bit / 96 kHz AES / ADAT Dual Format Converter 8-Channels ADAT® optical from / to AES/EBU Interface AES-3 24 Bit Interface
Contents 1 2 3 4 Introduction ........................................................................................................3 Supplied Contents .............................................................................................3 Brief Description and Characteristics..............................................................3 Technical Specifications ...................................................................................4 4.1 Inputs.........................................
1. Introduction With the ADI-8 DD you have an incredibly compact and flexible digital interface to your supply. What at first looks like a simple AES/ADAT format converter, turns out to be a universal problem solver at a closer look. From small project studios to broadcast and television, the ADI-4 DD is the perfect link between the formats mostly used today.
. Technical Specifications • • • • • Power supply: External power supply, 100-240 V AC, 10 Watts Accepted power supply voltage: DC 7 V – 38 V, AC 7 V – 27 V Current at 12 V: > 400 mA (> 5 Watts) Dimensions: 215 x 44 x 100 mm Weight: 1 kg 4.1 Inputs AES/EBU • • • • • • • • • 1 x XLR, 4 x via 25 pin D-Sub, transformer balanced, ground-free, according to AES3-1992 High-sensitivity input stage (< 0.
4.2 Outputs AES/EBU • • • • • • 1 x XLR, 4 x via 25 pin D-Sub, transformer balanced, ground-free, according to AES3-1992 Output voltage Professional 4.5 Vss, Consumer 2.
5. First Usage 5.1 Quick Start The user interface of the ADI-4 DD is characterized by a clearly structured architecture and an unambiguous labelling of the front and rear sides. The device can thus be used easily without a manual, because numerous LEDs show the state of the device and of all incoming and outgoing signals in a strictly logical way. After connection of the power supply, all LEDs on the front panel will be lit for a short time.
5.2 Operation Join us for a small 'tour de ADI', starting on the left side with the choice of the currently used input for the input channels 1/2. This is done via the key AES 1. Options are the XLR socket on the rear, the 25 pin D-Sub connector, and the optical input IN 2. The LED OPT is red, to signal that the ADAT input is no longer available. The state of the input signal is displayed by 13 LEDs. Shown are Lock (per AES and ADAT input, including SyncCheck), Double Speed (64/88.
6. The AES to ADAT Converter 6.1 General This functional unit is an 8-channel format converter from AES to ADAT. As long as the device is not working in DS mode (Double Speed), the output signal is present at both ADAT (OUT 1/OUT 2). Therefore the ADI-4 DD can pass on a 4 x 2 channel AES/EBU input signal to up to two ADAT devices at the same time (splitter 1 to 2). The four AES/EBU inputs process Double Speed (up to 96 kHz) and Double Wire (up to 48 kHz) automatically.
Notes on special functions The second ADAT input (IN 2) can be selected as source of channels 1/2 by the key AES 1, in case an optical SPDIF signal is present. This allows for example to convert the signal of a CDplayer into ADAT format. Of course, a simultaneous conversion of ADAT to AES is no longer available. If only one AES input is supplied with a valid signal, the ADI-4 DD switches to a distribution mode. The input signal will then be copied to all 8 ADAT outputs (splitter 1 to 4). 6.
7. The ADAT to AES/EBU Converter 7.1 General This functional unit is an 8-channel format converter from ADAT to AES/EBU. Because the Double Wire and Sample Split (S/MUX) formats don't contain a coding, the ADI-4 DD cannot distinguish them from normal (44.1/48 kHz) material. Whether the AES/EBU outputs are supposed to work in Single (44.1/48 kHz) or Double Speed (88.2/96 kHz) has to be set explicitly by the user. This happens in the section DS MODE by activating AES.
7.3 Input State Display The input state is being displayed by means of 4 LEDs. Each input has its own SYNC LED. When SYNC is set to ADAT, a missing or invalid input signal is indicated by slow flashing of the ADAT LED. If IN 1 and IN 2 are not synchronous to each other, the corresponding input's SYNC LED will be quickly flashing. If ADAT is not chosen as clock reference, SyncCheck takes the chosen clock (WC, AES) as reference and compares it to the clocks of the ADAT inputs.
Notes on special functions Using the AES STATE key the second ADAT output can be configured to act as optical SPDIF output. When choosing AES STATE OPT., the red LED is lit constantly, and the channels 1/2 will also be transmitted via OUT 2. 7.5 Double Wire Conversion The ADI-4 DD is able to convert AES Double Wire into Single wire and vice versa. For this application the ADAT I/Os have to be bridged (connect IN 1 with OUT 1, IN 2 with OUT 2). ADAT must not be chosen as clock source (SYNC).
8. Clock Section 8.1 Clock Configuration The ADI-4 DD has a common clock section for both converters, with professional capabilities that are hard to meet. The unique ICC technology (Intelligent Clock Control) offers professional features with simplest usage. All options are easily applicable and understandable, thanks to a clear display of the corresponding lock state. As SYNC source, WC (Wordclock), ADAT (IN 1 / IN 2) and AES (AES 1: XLR, Sub-D, IN 2) can be chosen.
8.3 Word Clock Input and Output Input The ADI-4 DD's word clock input is active when SYNC WC is chosen. The signal at the BNC input can be single or double speed, the ADI-4 DD automatically adapts to it. As soon as a valid signal is detected, the WC LED is constantly lit, otherwise it is flashing slowly. Thanks to RME's Signal Adaptation Circuit, the word clock input still works correctly even with heavily mis-shaped, dc-prone, too small or overshoot-prone signals.
9. Word Clock 9.1 Operation and Technical Background In the analog domain one can connect any device to another device, synchronization is not necessary. Digital audio is different. It uses a clock, the sample frequency. The signal can only be processed and transmitted when all participating devices share the same clock. If not, the signal will suffer from wrong samples, distortion, crackle sounds and drop outs.
9.2 Cabling and Termination Word clock signals are usually distributed in the form of a network, split with BNC T-adapters and terminated with resistors. We recommend using off-the-shelf BNC cables to connect all devices, as this type of cable is used for most computer networks. You will find all the necessary components (T-adapters, terminators, cables) in most electronics and/or computer stores. The latter usually carries 50 Ohms components.
10. Conversion Modes and Notes In this chapter the ADI-4 DD's conversion modes are listed. 10.1 8-channel AES to ADAT Converter (96 kHz) SOURCE: AES Remark: For sample rates higher than 56 kHz the DS LED lights up, and the outputs automatically work in Sample Split mode. Each output port (OUT 1 / OUT 2) then carries 4 channels. 10.2 8-channel AES to 2 x ADAT Splitter (48 kHz) SOURCE: AES Remark: For sample rates below 56 kHz the outputs OUT 1 and OUT 2 will carry the same data.
10.6 4-channel AES Single Wire to AES Double Wire Converter (96 kHz) SOURCE: AES Remark: When DS is not active and the input signal is in Single Wire Double Speed format, the data will be converted to Double Wire Single Speed. Because only 8 physical output channels are available, there will only be 4 audio channels effectively. The inputs 5 - 8 cannot be transmitted via AES. For this application, the ADAT ports have to be bridged with a loop-back cable (OUT 1 to IN 1, OUT 2 to IN 2).
11. Technical Background 11.1 DS - Double Speed When activating the Double Speed mode the ADI-4 DD operates at double sample rate. The internal clock 44.1 kHz turns to 88.2 kHz, 48 kHz to 96 kHz. The internal resolution is still 24 bit. Sample rates above 48 kHz were not always taken for granted, and are still not widely used because of the CD format (44.1 kHz) dominating everything. Before 1998 there were no receiver/transmitter circuits available that could receive or transmit more than 48 kHz.
11.2 AES/EBU - SPDIF The most important electrical properties of 'AES' and 'SPDIF' can be seen in the below table. AES/EBU is the professional balanced connection using XLR plugs. The standard is being set by the Audio Engineering Society based on the AES3-1992. For the 'home user', SONY and Philips have omitted the balanced connection and use either phono plugs or optical cables (TOSLINK). The format called S/P-DIF (SONY/Philips Digital Interface) is described by IEC 60958.
12.
13. Connector Pinouts D-Sub The 25 pin D-sub connector provides all 4 AES inputs and outputs. The actual pinout is defined by a special coding connector within the ADI-4 DD. To gain access to the coding connector, the cover has to be removed. The coding connector is attached to a flat ribbon cable, and can be plugged into three different multipin connectors. X229: Euphonix X230: Yamaha X231: Tascam / Digidesign X231 is the factory's default setting, and resides next to the front plate.
AES/EBU The XLR connectors are wired according to AES3-1992: 1 = GND (shield) 2 = Signal 3 = Signal AES/EBU and SPDIF are biphase modulated signals, therefore polarity doesn't matter. Pins 2 and 3 are neither hot nor cold, they carry the same signal. But as AES3 uses a balanced transmission they are inverted in polarity.
14.
15. Warranty Each individual ADI-4 DD undergoes comprehensive quality control and a complete test at IMM before shipping. The usage of high grade components should guarantee a long and trouble-free operation of the unit. If you suspect that your product is faulty, please contact your local retailer. Audio AG grants a limited manufacturer warranty of 6 months from the day of invoice showing the date of sale. The length of the warranty period is different per country.
CE This device has been tested and found to comply with the limits of the European Council Directive on the approximation of the laws of the member states relating to electromagnetic compatibility according to RL2004/108/EG. FCC This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation.
