User's Guide ADI-642 Multichannel Audio Digital Interface SyncAlign TM TM SyncCheck Intelligent Clock Control TM TM SteadyClock Hi-Precision 24 Bit / 192 kHz MADI - AES/EBU Interface 8-Channel / 64-Channel Format Converter Analog 24 Bit / 192 kHz Stereo Monitor 72 x 74 Matrix Router MIDI embedded in MADI RS232 embedded in MADI
General 1 2 3 4 Introduction ...............................................................6 Package Contents .....................................................6 Brief Description and Characteristics.....................6 First Usage - Quick Start 4.1 Controls and Connectors .......................................7 4.2 Quick Start .............................................................8 5 Warranty.....................................................................9 6 Appendix ...................
Technical Reference 13 Technical Specifications 13.1 Inputs ................................................................... 30 13.2 Outputs ................................................................ 30 13.3 MIDI – RS232 ...................................................... 31 13.4 Digital ................................................................... 31 13.5 General ................................................................ 32 13.6 Firmware ............................................
Important Safety Instructions ATTENTION! Do not open chassis – risk of electric shock The unit has non-isolated live parts inside. No user serviceable parts inside. Refer service to qualified service personnel. Mains • The device must be earthed – never use it without proper grounding • Do not use defective power cords • Operation of the device is limited to the manual • Use same type of fuse only To reduce the risk of fire or electric shock do not expose this device to rain or moisture.
User's Guide ADI-642 General User's Guide ADI-642 © RME 5
1. Introduction With the ADI-642 you have an incredibly versatile digital interface to your supply. What at first looks like a simple MADI/AES format converter, turns out to be a very flexible tool at a closer look. From small project studios to broadcast and television, this Advanced Digital Interface is the perfect solution for many tasks. As a consequent continuation of RME's world-wide successful ADI series, the 642 also contains elaborate technology and the latest integrated circuits.
4. First Usage – Quick Start 4.1 Controls and Connectors The front of the ADI-642 features nine buttons, one rotary encoder, 38 LEDs and four seven segment displays, providing all necessary means for a detailed configuration of the unit. MADI INPUT determines the current input for the MADI signal (optical/coaxial). Additionally, a detailed input state display analyses and presents the input signal status. MADI OUTPUT is used to configure the MADI output as 56/64 channel or 48k/96k frame format.
4.2 Quick Start Configuration starts with choosing the MADI input, BNC or optical. The state of the input signal is displayed by 14 LEDs. Shown are active input, automatic input selection, receiver state, Sync, 56 or 64 channel format, 48k frame or 96k frame, and audio data within 8-channel groups. The Sync LED shows the synchronicity between input signal and external/internal clock, or between the active inputs. The MADI output signal can include 56 or 64 channels (FORMAT).
5. Warranty Each individual ADI-642 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 / FCC Compliance 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, and European Low Voltage Directive RL2006/95/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.
User's Guide ADI-642 Usage and Operation User's Guide ADI-642 © RME 11
7. Front panel Controls 7.1 MADI INPUT The button INPUT sets the input to optical or coaxial. The section INPUT STATE helps to avoid errors caused by wrong, missing or not correctly connected inputs, and makes handling the digital MADI format much easier. A total of 14 LEDs display the state of the current input signal. The SYNC LED lights up as soon as a valid signal is present at the input. An un-synchronous input signal will be signalled by flashing of the SYNC LED.
7.4 CLOCK The source and frequency of the unit's clock is configured in the CLOCK SECTION. The button CLOCK lets you step through the options external clock (AES, MADI, word) and internal clock (44.1 or 48 kHz). The button STATE sets internal, but also the external sample rate to double or quadruple of the basic sample rate. AES, MADI, WCK (Slave Mode) Defines the corresponding input as clock reference. A missing or invalid clock source signal is indicated by flashing of the corresponding LED.
7.5 REMOTE The button REMOTE is used to select the source of the MIDI remote control commands, and also the destination for the ADI-642's request replies. The standard MIDI ports or the MADI input and output can be chosen. In order to remote control multiple ADI-642 that are connected in a serial way, without the need of using an external MIDI splitter and merger, the ADI-642 passes on all MIDI data from the MADI input to the MADI output. This way no further external cabling is necessary.
ADC The Auto Delay Compensation realizes an offset compensation when using multiple ADI-642 connected serially (see chapter 12). For this, ADC is activated at the first unit of the chain, turning the unit into the ADC Master. The blue LED lights up bright. Immediately the blue LEDs of all other units light up less bright automatically. These units are now ADC Slaves*. The display shows an information about the unit's current position within the chain (id 02 or higher).
7.7 MONITOR The 192 kHz capable stereo monitor output can be used to monitor any of the input channels. Setup is done by selecting OUTPUT Ph in the matrix section. Ph can be assigned to any of the input channels, but always uses the next input channel as well. So when selecting 02 the MADI channel 2 is sent to the left output, MADI channel 3 will be sent to the right output. The low impedance driver stage is capable of driving headphones. The output level can be adjusted manually via the VOL pot.
Emphasis AES/EBU and SPDIF can contain an Emphasis information. Audio signals with Emphasis have a strong high frequency boost and thus require a high frequency attenuation on playback. An Emphasis indication gets lost! This information is neither passed on to the MADI output, nor to any of the AES outputs! 9. Outputs 9.1 MADI At the rear side of the ADI-642 there are two MADI outputs. The BNC output is built according to AES10-1991. The output's impedance is 75 Ohm.
10. Word Clock 10.1 Word Clock Input and Output SteadyClock guarantees an excellent performance in all clock modes. Its highly efficient jitter suppression refreshes and cleans up any clock signal, and provides it as reference clock at the BNC output (see section 14.5). Input The ADI-642's transformer isolated word clock input is active when WCK is chosen in the clock section. The signal at the BNC input can be Single, Double or Quad Speed, the ADI-642 automatically adapts to it.
10.2 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.
10.3 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 Ohm components.
11. MIDI and RS232 11.1 MIDI Transmission MADI allows for a transmission of 64 audio channels over long distances with a single line – perfect. But what about MIDI? Be it remote control commands or sequencer data, in practice only a single MADI line will not suffice. Therefore the ADI-642 also has a MIDI I/O port. The data at the MIDI input are being included into the MADI signal invisibly, and can be collected at the MIDI output of another ADI-642, ADI-648 or a HDSP MADI, at the other end of the MADI line.
11.3 Remote Control Software The Windows and Mac software MIDI Remote can be downloaded for free from the RME website. It uses a MIDI port within the system to perform remote control and status requests of all ADI-642 via a simple mouse click. Most appealing is the combination with a HDSP MADI (PCI card), offering a direct control of the ADI-642 via MADI. The remote control software then uses a virtual MIDI port of the card (port 3), which directly sends and receives MIDI data via MADI.
Options – Select Device Opens a dialog box to select a device ID. Choosing 'All', the current device ID of the unit is ignored. The setting 'All' is not allowed when using more than one ADI-642. Options – Program Device ID Opens a dialog box to program a device ID into the ADI-642. Note: programming is fast and not confirmed. Attention: Programming requires to connect not more than one ADI-642 via MIDI! Via MIDI remote control, all front panel controls of the ADI-642 can be locked (Lock Keys).
12. Application Examples 12.1 Digital AES/EBU Breakout box As MADI from/to AES/EBU converter the ADI-642 is an ideal breakout box for RME's HDSP MADI PCI card. In order to convert the 64 channels of the MADI card to AES up to eight ADI642 will be connected in a serial way. But as every ADI-642 causes a MADI I/O delay of 3 samples, the AES inputs and outputs of different ADI-642s are not sample-aligned, but differently delayed.
The application breakout box/computer unveils another delay, the so called offset between playback and recording. If a signal is played back from the MADI PCI, and recorded again via MADI by performing an AES loopback, the record track will show a specific delay against the playback track. The reason for this is that the HDSP MADI does signal its own offset to the application, but not the ones of externally connected devices – which it can't know anyway.
User's Guide ADI-642 © RME
12.3 MADI to MADI Converter MADI has been used for quite some time now and therefore not all interfaces from different manufacturers are compatible with each other. An AMS Neve Logic DFC e. g. only accepts the 56 channel input format and when a 64 channel signal is applied, the whole input is muted. There exist lots of other but similar examples. The ADI-642 can serve here as a perfect link, because its MADI input can read any input format.
Example 1: A mixing desk sends 48 channels via MADI. 8 more channels from a RME OctaMic-D (8-channel microphone preamp with AES output) shall be recorded by a HDSP MADI into a computer. This application requires one ADI-642, which has to be inserted into the MADI line. The Routing Matrix is used to loop channels 1 to 48 from MADI input to MADI output. The OctaMic-D will be connected to the four AES inputs.
User's Guide ADI-642 Technical Reference User's Guide ADI-642 © RME 29
13. Technical Specifications 13.1 Inputs MADI • Coaxial via BNC, 75 Ohm, according to AES10-1991 • High-sensitivity input stage (< 0.2 Vpp) • Optical via FDDI duplex SC connector • 62.5/125 and 50/125 compatible • Accepts 56 channel and 64 channel mode, and 96k frame • Single Wire: up to 64 channels 24 bit 48 kHz • Double Wire: up to 32 channels 24 bit 96 kHz • Lock range: 28 kHz – 54 kHz • Jitter when synced to input signal: < 1 ns • Jitter suppression: > 30 dB (2.
AES/EBU • 4 x XLR, transformer balanced, ground-free, according to AES3-1992 • Output voltage Professional 4.5 Vpp • Format Professional according to AES3-1992 Amendment 4 • Format Consumer (SPDIF) according to IEC 60958 • Single Wire: 4 x 2 channels 24 bit, up to 192 kHz Word Clock • BNC • Max. output voltage: 5 Vpp • Output voltage @ 75 Ohm: 4.0 Vpp • Impedance: 10 Ohm • Frequency range: 28 kHz – 220 kHz DA - Stereo Monitor Output (Phones) • Resolution: 24 bit • Dynamic range (DR): 108 dB, 110 dBA @ 44.
13.5 General • • • • • • • Power supply: Internal switching PSU, 100 - 240 V AC, 20 Watt Typical power consumption: 6 Watt Dimensions including rack ears (WxHxD): 483 x 44 x 242 mm (19" x 1.73" x 9.5") Dimensions without rack ears/handles (WxHxD): 436 x 44 x 235 mm (17.2" x 1.73" x 9.3") Weight: 2 kg ( 4.4 lbs) Temperature range: +5° up to +50° Celsius (41° F up to 122°F) Relative humidity: < 75%, non condensing 13.6 Firmware The ADI-642's main part has been realized using programmable logic.
14. Technical Background 14.1 Terminology Single Speed Sample rate range originally used in Digital Audio. Typical applications are 32 kHz (digital radio broadcast), 44.1 kHz (CD), and 48 kHz (DAT). Double Speed Doubles the original sample rate range, in order to achieve higher audio quality and improved audio processing. 64 kHz is practically never used, 88.2 kHz is quite rare in spite of certain advantages. 96 kHz is a common format. Sometimes called Double Fast.
14.2 Lock, SyncCheck and SyncAlign Digital signals consist of a carrier and the data. If a digital signal is applied to an input, the receiver has to synchronize to the carrier clock in order to read the data correctly. To achieve this, the receiver uses a PLL (Phase Locked Loop). As soon as the receiver meets the exact frequency of the incoming signal, it is locked. This Lock state remains even with small changes of the frequency, because the PLL tracks the receiver's frequency.
14.3 AES/EBU - SPDIF The most important electrical properties of 'AES' and 'SPDIF' can be seen in the table below. 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.
14.4 MADI Basics MADI, the serial Multichannel Audio Digital Interface, has been defined already in 1989 as an extension of the existing AES3 standard following several manufacturers' wish. The format also known as AES/EBU, a balanced bi-phase signal, is limited to two channels. Simply put, MADI contains 28 of those AES/EBU signals in serial, i. e. after one another, and the sample rate can still even vary by +/-12.5%. The limit which cannot be exceeded is a data rate of 100Mbit/s.
14.5 SteadyClock The SteadyClock technology of the ADI-642 guarantees an excellent performance in all clock modes. Its highly efficient jitter suppression refreshes and cleans up any clock signal, and provides it as reference clock at the word clock output. Usually a clock section consists of an analog PLL for external synchronization and several quartz oscillators for internal synchronization. SteadyClock requires only one quartz, using a frequency not equalling digital audio.
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16. MIDI Implementation Chart ADI-642 16.1 Basic SysEx Format Value Name F0h 00h 20h 0Dh 62h 00h..7Eh, 7Fh mm nn oo F7h SysEx header MIDITEMP manufacturer ID Model ID (ADI-642) Device ID. 7Fh = broadcast (all IDs) Message type Parameter number (see table 1) Data byte EOX 16.2 Message Types Value Name 10h 20h 30h Request value Set value Value response Request Value Format: F0 00 20 0D 62 (dev ID) 10 F7 This string triggers a complete dump of all value response data bytes.
16.4 Table Set Value Value Resp. Data bytes No. No.
30h 31h 32h 33h 34h 35h 36h 37h 38h 39h 3Ah 3Bh 3Ch 3Dh 3Eh 3Fh 40h 41h 42h 43h 44h 45h 46h 47h 48h 49h 4Ah 4Bh 4Ch 4Dh 4Eh 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 4Fh 50h 51h 52h 53h 54h 55h 56h 57h 79 80 81 82 83 84 85 86 87 58h 88 MADI output channel 64 AES output channel 1 AES output channel 8 phones output (left) matrix output display settings byte 1 settings byte 2 MADI audio 1..4 MADI audio 5..8 AES audio 1..
50h 80 settings byte 1 MSB / 7 6 5 4 3 2 1 LSB / 0 0 madi input: 0 = BNC, 1 = opt 0 madi frame: 0 = 48k, 1 = 96k madi format: 0 = 56ch, 1 = 64ch MSB / 2 clock select: 0 = int 44.
