ADC ADDC1 instruction manual What UltraLock converters cannot do

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Is it possible to eliminate all of the effects of jitter in an entire digital audio system?

Interface jitter will accumulate throughout even the most carefully designed digital audio system. Fortunately, interface jitter can only degrade digital audio if it affects the sampling circuit in an analog-to-digital or analog-to- digital converter. Any attempt to cure jitter outside of an ADC or DAC will prove expensive and, at best, will only partially reduce jitter-induced artifacts. Dedicated clock signals (word clock, and super clock, etc.) are often distributed to A/D converters and D/A converters in an attempt to reduce jitter. Again, these are only partial solutions because jitter even accumulates in these clock distribution systems. Furthermore, a poor quality master clock generator can degrade the performance of the entire system (if converter performance is dependent upon reference clock quality. Jitter free ADCs and DACs are the only true insurance against the ill effects of jitter. UltraLock converters are jitter immune under all operating conditions (they will never add audible jitter induced artifacts to an audio signal).

What UltraLock converters cannot do

UltraLock converters cannot undo damage that has already been done. If an ADC with a jitter problem was used to create a digital audio signal, then there is nothing that can be done to remove the damage. Jitter-induced sidebands are extremely complex and cannot be removed with any existing audio device. It is therefore important to attack jitter at both ends of the audio chain. The ADC1 is a great start, as it will allow accurate assessment of various A/D converters. It is impossible to evaluate ADC performance without a good DAC. The consistent performance delivered by the ADC1 eliminates one major variable: jitter.

ADC1 Instruction Manual

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Contents Channel 24-bit 192-kHz Audio Analog-to-Digital Converter Benchmark ADC1Federal Communications Commission FCC Notice Only Safety InformationContents Overview Page Features To adapt to unbalanced sources ConnectionsBalanced Analog Line Inputs Clock Reference InputAES/EBU XLR Output Digital OutputsOptical Output SPDIF/AES BNC Main and Aux Outputs Adat Optical Output ModeAdat S/MUX2 Optical Output Mode Adat S/MUX4 Optical Output ModeWord Clock Reference Output AC Power Entry ConnectorFuse Holder Programming the Outputs Mode Switch and DisplayTo program the conversion mode OperationTo select a fixed sample frequency on the Main Outputs Selecting a Fixed Frequency Using the Internal Clock SourceReading Sample Rates off of the Mode Display To synchronize with an external clock sourceMeter Display Resetting the ADC1 to Factory Default SettingsProgramming the Aux Output Adat or AES/EBU on the Optical OutputFirst Stage Gain Adjusting Input GainSecond Stage Gain Controls Rack Mounting MUX should not be used for Sample Rate Conversion Using Adat S/MUXProper S/MUX Identification is a Must Sample Rate is the Key that Controls S/MUXUltraLock … What is It? Put UltraLock converters to the test Problem #1What UltraLock converters cannot do Frequency Response PerformanceInter-Channel Phase Response THD+N vs. Level, 1 KHz KHz LPF unweighted32K B-H FFT, Idle Channel Noise 32K B-H FFT, -3 dBFS, 1 KHz 32K B-H FFT, -3 dBFS, 10 KHz Analog Audio Inputs SpecificationsWorldclock Reference Output Digital Audio Outputs Audio Performance LED Status Indicators Group Delay LatencyDimensions AC Power RequirementsWeight Page Benchmark 1 Year Warranty Warranty InformationBenchmark Extended Warranty Benchmark Extended 5* Year WarrantyBenchmark Media Systems, Inc