Intel Fireface 800 manual Technical Background, Lock and SyncCheck

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37. Technical Background

37.1 Lock and SyncCheck

Digital signals consist of a carrier and the data. If a digital signal is applied to an input, the re- ceiver 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 fre- quency 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.

If an ADAT or SPDIF signal is applied to the Fireface 800, the corresponding input LED starts flashing. The unit indicates LOCK, i. e. a valid input signal (in case the signal is also in sync, the LED is constantly lit, see below).

Unfortunately, LOCK does not necessarily mean that the received signal is correct with respect to the clock which processes the read out of the embedded data. Example [1]: The Fireface is set to 44.1 kHz internally (clock mode Master), and a mixing desk with ADAT output is con- nected to input ADAT1. The corresponding LED will show LOCK immediately, but usually the mixing desk's sample rate is generated internally (also Master), and thus slightly higher or lower than the Fireface's internal sample rate. Result: When reading out the data, there will frequently be read errors that cause clicks and drop outs.

Also when using multiple inputs, a simple LOCK is not sufficient. The above described problem can be solved elegantly by setting the Fireface from Master to AutoSync (its internal clock will then be the clock delivered by the mixing desk). But in case another, un-synchronous device is connected, there will again be a slight difference in the sample rate, and therefore clicks and drop outs.

In order to display those problems optically at the device, the Fireface includes SyncCheck®. It checks all clocks used for synchronicity. If they are not synchronous to each other (i. e. abso- lutely identical), the SYNC LED of the asynchronous input flashes. In case they are completely synchronous, all LEDs are constantly lit. In example 1 it would have been obvious that the LED ADAT 1 kept on flashing after connecting the mixing desk.

In practice, SyncCheck allows for a quick overview of the correct configuration of all digital de- vices. So one of the most difficult and error-prone topics of the digital studio world finally be- comes easy to handle.

The same information is presented in the Fireface's Settings dialog. In the status display Sync- Check the state of all clocks is decoded and shown as simple text (No Lock, Lock, Sync).

User's Guide Fireface 800 © RME

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Contents TotalMix Bit / 192 kHz SyncAlignZLMSyncCheck SteadyClock Most powerful FireWire audio interface everGeneral Installation and Operation WindowsInstallation and Operation Mac OS Stand-Alone Operation, Connections and TotalMix Technical Reference Mains Important Safety InstructionsInstallation Users Guide Fireface 800 RME General System Requirements Package ContentsBrief Description and Characteristics IntroductionFirst Usage Quickstart Connectors and Front PanelPart Number Description AccessoriesQuick Start Trademarks WarrantyAppendix Users Guide Fireface 800 RME ISO CE / FCC ComplianceRoHS Users Guide Fireface 800 RME Installation and Operation Windows Desktop Computer Hardware InstallationDriver Installation Driver and FirmwareFirmware Update Driver UpdateDeinstalling the Drivers Settings dialog General Configuring the FirefaceLimit Bandwidth Phantom PowerBuffer Size InputsOptions Clock ModeWord Clock Out SyncCheckSettings dialog DDS Application examples Clock Modes SynchronizationLimit Bandwidth Available SettingsPlayback Operation and UsageMultichannel DVD-Playback AC-3/DTSAC-3 / DTS Low Latency under MME Buffer Size Adjustment Fireface Analog 1+2 MME Fireface Analog 1+2ASIO-Multiclient Multi-Client and Multi-Channel using WDMMulti-client Operation Digital Recording Analog Recording Operation under AsioWindows 2000/XP Known ProblemsCommon Problems Operation under Gsif Gigasampler InterfaceUsing more than one Fireface DIGICheck 8 Adat channels don’t seem to work Hotline TroubleshootingInstallation Channel Routing Asio at 96 kHz DiagramsChannel Routing MME at 96 kHz Users Guide Fireface 800 RME Mac OS X Installation and Operation Driver Firmware Update Configuring the Fireface Level Out LevelAutoSync Ref Settings dialog DDS Clock Modes Synchronization Limit Bandwidth Midi doesnt work Mac OS X FAQRound about Driver Installation Various Information Repairing Disk PermissionsFireWire Compatibility Supported Sample RatesPossible causes for a Fireface not working Multicard OperationDiagram Channel Routing at 96 kHz Users Guide Fireface 800 RME Stand-Alone Operation, Connections and TotalMix Stand-alone Operation Reference DBFS @ Headroom Analog InputsLine Rear Microphone / Line FrontSpeaker Emulation InstrumentDrive Line HeadphonesAnalog Outputs Spdif Digital ConnectionsAdat Midi Special Characteristics of the Spdif OutputOutput Word ClockWord Clock Input and Output InputTechnical Description and Usage Operation Cabling and TerminationOverview TotalMix Routing and MonitoringUsers Guide Fireface 800 RME User Interface Tour de TotalMix Elements of a ChannelUsers Guide Fireface 800 RME Mute and Solo Submix ViewPresets Quick Access PanelPreset Banks PresetPreferences Monitor PanelStereo Pan Law Editing the NamesMain Monitor Hotkeys Menu Options Level Meter Elements of the Matrix View TotalMix The MatrixAsio Direct Monitoring Windows only TotalMix Super-FeaturesAdvantages of the Matrix Delete Routings Selection and Group-based OperationCopy Routings to other Channels Recording a Subgroup Loopback Recording a Softwares playback Using external Effects DevicesMixing several input signals into one record channel MS Processing Meaning in TotalMix Midi Remote ControlMapping ElementSetup Monitor Main 3E / 62 / D Preset 3 38 / 56 / #GPreset 5 3A / 58 / #A Simple Midi ControlLoopback Detection Meaning in Fireface Stand-Alone Midi ControlMackie Control Protocol Simple Midi Control Element Meaning in FirefaceUsers Guide Fireface 800 RME Technical Reference Tech Info Analog Technical SpecificationsDA Stereo Monitor Output Phones DigitalDA, Line Out 1-8, rear Adat Optical Digital InputsDigital Outputs Transfer Modes Resolution / Bits per Sample Windows onlyLock and SyncCheck Technical BackgroundSample frequency kHz 44.1 88.2 176.4 192 Latency and MonitoringHow much Zero is Zero? OversamplingCore Audios Safety Offset FireWire AudioSafety Buffer Limit Bandwidth 48 kHz 96 kHz 192 kHz FW-Kanäle Number of Channels and Bus LoadQS Quad Speed Analog DS Signal PortDS Double Speed Type AES3-1992 IEC Byte Mode BitSteadyClock Noise level in DS / QS ModeBlock Diagram Fireface TRS Phones jack Connector PinoutsTRS jacks of analog input / output XLR jacks of analog inputs

Fireface 800 specifications

The Intel Fireface 800 is a powerful audio interface celebrated for its high-performance capabilities and versatility in both studio and live settings. Designed to cater to the needs of musicians, producers, and sound engineers, it stands out with its rich feature set and reliable technology.

One of the defining features of the Fireface 800 is its support for an impressive 26 input and 28 output channels. This extensive I/O configuration facilitates seamless integration with a wide variety of audio production setups, allowing users to record multiple instruments simultaneously or create complex routing scenarios. The unit also boasts top-notch analog and digital converters, ensuring pristine sound quality with a dynamic range that captures the nuances of any audio source.

In terms of connectivity, the Fireface 800 is equipped with both FireWire and USB ports, making it compatible with a range of computers and devices. The device utilizes the FireWire 800 protocol, which delivers higher data transfer rates compared to its predecessor. This efficient transfer capability is crucial for maintaining audio fidelity and reducing latency, making it an ideal choice for real-time monitoring and recording.

The Fireface 800 also features standalone operation capabilities, functioning independently of a computer when needed. This is particularly useful for live performances, where reliability and reduced setup complexity are essential. Users can easily connect microphones, instruments, and other equipment directly to the Fireface 800, making it a versatile tool for a variety of scenarios.

With its low-latency driver technology, the Fireface 800 ensures smooth performance even when handling demanding audio tasks. Its advanced ADAT and S/PDIF digital inputs and outputs provide further flexibility for connecting other gear, such as additional preamps and effects processors.

Another noteworthy characteristic of the Fireface 800 is its robust build quality. Designed for regular use in professional environments, the unit features a rugged metal chassis that can withstand the rigors of transport and daily use. This ensures longevity and consistent performance for audio professionals who depend on reliable equipment day in and day out.

In summary, the Intel Fireface 800 is a versatile and powerful audio interface that caters to a wide spectrum of audio production needs. With its extensive I/O capabilities, high-quality converters, reliable connectivity options, and robust design, it continues to be a popular choice among audio professionals striving for excellence in their work.