The Clearest eCe e Path to Digital! oD P
The AD-1000 20-bit A/D Converter from Apogee Electronics Corporation
Supports common digital audio formats including AES/EBU, S/PDIF and ADAT Ultra low-noise mic amps with phantom power Exclusive UV22 encoding for flawless conversion to 16-bit Soft Limit processing for analog-like performance New Platinum Edition includes digital pass-through; DA-88 interfacing (with stand-alone FC-8 format converter); PaqRat-compatible 20-bit recording.
AD-1000 20-bit resolution analog to digital conversion system is the combination of years of design expertise with the practical real world requirements of thousands of Apogee users. Descended from the industry standard AD-500E , the AD-1000 adds 20-bit resolution with selectable UV22 encoding, ADAT optical output, digital oscillator and transparent microphone preamps. Portable 12 volt operation and dual stage, triple servo, direct coupled microphone preamps Apogee Electronics: with phantom power let you take reference ten years of standard conversion wherever you go. Effective dedication to input peak metering and Over indication ease better digital audio. the adjustment of separate mic gain and multiturn CAL controls. Select the acclaimed SoftLimit function to position your recordings above the competition. A special version of Apogees UV22 process captures 20 bit resolution and detail into 16-bit formats such as CD, DAT and ADAT. UV22 encoding is the overwhelming choice of mastering engineers world wide for condensing high resolution sources onto CDs. Outputs can be ADAT optical or simultaneous AES and S/PDIF to support multiple recorders. Optional outputs include SDIF, SDIF-II and Tascam TDIF. With the input selector set to DIGITAL, AES or S/PDIF inputs are converted to all outputs. A built-in digital oscillator outputs all popular 0 reference levels for precise headroom setting. Patented Apogee Low Jitter Clock technology

POGEES

assures all digital outputs are free of the negative effects of clock jitter. The AD-1000 can operate as a Sync Master or lock to external AES, S/PDIF or Word Clock. Film and Video are supported by NTSC color, monochrome and PAL inputs. Transfer and repair operations are further enhanced with Apogees 1.001 circuit, allowing pull-up and pull-down. Dont settle for shortcuts to digital. Your projects deserve the best. The clearest path from analog to digital is through Apogees AD-1000. Listen to the results for yourself at your nearest Apogee authorized dealer.

The digital masters.

APOGEE ELECTRONICS CORPORATION,
3145 Donald Douglas Loop South, Santa Monica, CA 90405. Tel: 310/915-1000 Fax: 310/391-6262 Email: info@apogeedigital.com Web: http://www.apogeedigital.com/
Illustration by Trici Venola. Trademarks and registered trademarks are the property of their respective owners.
AD-1000 Specifications and Features

SPECIFICATIONS

QUANTIZATION FREQUENCY RESPONSE 20 Bits/Sample 20Hz10kHz 0.025dB 10kHz20kHz +0.025 / 0.1dB TOTAL HARMONIC DISTORTION PLUS NOISE (THD+N) Full Amplitude Typically 100dB @ 48kHz sampling; 0.5dB below full scale 20dB scaled to Fs Typically 103dB@ 48kHz sampling; 0.5dB below full scale SIGNAL TO NOISE RATIO Typically 104dB Unweighted, 109dB A weighted CROSSTALK Typically better than 110dB @ 1kHz SOFT LIMIT THRESHOLD 1.5dB below digital output full scale (adjustable) METERING THRESHOLDS Amber indicates 2dB below full scale (includes peak hold function and SoftLimit Threshold). Green indicates 12dB below full scale (adjustable) (includes peak hold function). Red indicates three full-scale samples in a row (Includes peak hold function) COMMON MODE REJECTION Typically better than 110dB@100Hz Typically better than 75dB @10kHz EXTERNAL SAMPLING RATE RANGE Any frequency from 32kHz to 54kHz via External Sync Input INTERNAL SAMPLING RATE 32kHz, 44.056kHz, 44.1kHz, 44.144kHz, 47.952 kHz, 48kHz or 48.048kHz SAMPLING RATE ACCURACY 10 PPM SAMPLING RATE INDICATOR Amber LEDs indicate output sampling rate range for 32kHz, 44kHz, and 48kHz INTERNAL CLOCK JITTER Typically 30 picoseconds RMS NOMINAL DC POWER INPUT 12vdc @ 1150-1300mA dependent upon function INPUT VOLTAGE +11.5 to +15 Volts DC (well regulated) INPUT DROPOUT 10.4 Volts DC LOW VOLTAGE IND. Power LED Flashes at <11.5vdc Power Input WEIGHT 1.3Kg (2 lbs 14 oz) DIMENSIONS L=273.0 x W=141.2 x H=39.6 mm (L=10.75 x W=5.56 x H=1.56 in) OPERATING TEMPERATURE 0C to 40C (32F to 104F) DIGITAL AUDIO INPUT STANDARD (UV22 processing for digital inputs available as an option) 32kHz54kHz input sampling rates. AES/EBU format (termination selectable at SYNC SOURCE switch to 110 or bridged by > 5 k). S/PDIF format (input bridged by > 5 k or 75 terminated dip switch selectable). S/PDIF DIGITAL OPTICAL INPUT (Optical input connector on rear panel) 32kHz to 54kHz Input Sampling Rates. ADAT DIGITAL OPTICAL INPUT available with special option AD1K-PRT

OUTPUTS

AES OUTPUT (Male XLR connector on rear panel) 32kHz to 54kHz Output Sampling Rate. AES/EBU Format when front panel NORM position selected. Audio Black when front panel ADAT position selected. S/PDIF OUTPUT (15 Pin HD connector on rear panel) 32kHz to 54kHz Output Sampling Rate. S/PDIF Format when front panel NORM position selected. OPTICAL OUTPUT (Toslink Optical output connector on rear) 32kHz to 54kHz Output Sampling Rate. S/PDIF or ADAT Format selectable on front panel power switch. WORD SYNC OUTPUT (15 Pin HD connector on rear panel) 32kHz to 54kHz Output Sampling Rate. Two types available: Balanced RS422 Compatible. Unbalanced TTL/Sony Compatible. 256 fs OUTPUT (15 Pin HD sub connector on rear panel)

OPTIONAL DIGITAL OUTPUTS

SDIF-II OUTPUT (15 Pin HD connector on rear panel) 32kHz to 54kHz Output Sampling Rate. Balanced - RS422 Compatible or Unbalanced TTL Compatible. HI-RESOLUTION OPTION AD1K-PRT (20 bit encoding and decoding across track pairs).Through a combination of enhancements to the AD-1000, a hi-resolution stereo output can be mapped to stereo pairs of ADAT (or TDIF with the FC-8 format converter) format tracks. This process is compatible with Ranes Paqrat format.

OPTIONAL ACCESSORIES

PS-1000E Rack mountable dual worldwide power source for the AD-1000 with selectable 100, 120, 220, and 240 Volts AC and 50/60Hz providing dual 1 12.0 Volts DC regulated outputs at 1500mA each. Unit is 3 rack size and matches style and finish of the AD-1000. Power is distributed by two 15 Pin HD connectors on the rear panel. This unit can power up to two Apogee converters (A/D or D/A). PS-1000E / AD-1000 Cable Interconnect from PS-1000 to AD-1000 for S/PDIF and Word Clock output operation (cable with a breakout of two female BNC connectors one for S/PDIF [red connector], the other for Word Clock output [white connector]. A male BNC to female adaptor is also provided. AD-1000 SDIF Option Adds SDIF and SDIFII output capability Left Data, Right Data and Word Clock via 15 Pin HD connector. RM-1000 Rack mountable carrier frame in Apogee purple, capable of holding up to three AD-1000, DA-1000E or PS-1000E in a 1U EIA space. RM-2000 An alternative racking frame which holds three units in a 2U space where ventilation is a problem. (Available 1997).
Note: The AD-1000 will work with any well regulated 12V DC Power source with an output current of 1300 mA or greater. We recommend using linear type power supplies. Direct connection to external 12V DC lead acid or NiCad batteries will provide convenient portable operation. INPUTS
ANALOG INPUTS (two 3 pin female XLR connectors on rear panel). Line Level: +4 dBu (Professional) nominal input level @ 10 k balanced (>5 k unbalanced). CAL +4 Maximum input peak level (front panel gain controls at minimum, fully counterclockwise) +28dBu balanced, +24dBu unbalanced. 10 dBu (consumer) nominal input level. Microphone Level: Minimum input peak level (Input Selector at Mic 40 and front gain controls at max): 54dBu Balanced, 50 dB Unbalanced (up to 54dB of gain is available). Phantom Power: Available in Mic Positions when Phantom Power Selector is enabled. ( 7mA available per channel to power condenser microphones.) SYNC INPUTS (Two male BNC connectors on rear panel). BNCs are paralleled for convenient looping to other units or termination (selectable termination). BNCs accept either balanced or unbalanced inputs. WORD SYNC (WC): 32kHz to 54kHz Input Sampling Rates. TTL or RS422 levels. (input bridged by > 5 k. Needs to be externally terminated @ 75 ). DIGITAL AUDIO SYNC: 32kHz to 54kHz Input Sampling Rates. AES/EBU Format (termination selectable at SYNC SOURCE switch to110 or bridged by > 5 k for looping to other devices). S/PDIF Format (input bridged by > 5 k or 75 terminated - switch selectable). ANALOG VIDEO: Black burst/Composite Sync/Composite Video. NTSC (525line/59.94Hz); Monochrome (525line/60Hz); PAL (625line/50Hz). (input bridged by > 5 k or 75 terminated dip switch selectable). OPTICAL SYNC INPUT: (Optical input connector on rear panel) 32kHz to 54kHz Input Sampling Rates. S/P DIF or AES/EBU Optical Format. In addition to Analog to Digital Conversion, the AD-1000 offers many Digital format conversion options. Depending on the options installed, the following digital input options are available when the DIG position is selected on the INPUT SELECTOR.

PLATINUM OPTIONS

AD1K-UVD (firmware option) UV22 Digital Through option allows a digital input signal to be UV22 processed (the standard unit only supports UV22 on signals generated by the A/D section from the analog inputs). AD1K-PRT (firmware option) 20-bit bidirectional ADAT interface option The standard AD-1000 provides an ADAT output. This upgrade adds ADAT input capability, plus the ability to record and play back two 20-bit signals by using two pairs of tracks on an ADAT machine. The 20-bit capability is compatible with Ranes PaqRat system. FC-8 (Stand-alone unit) Bidirectional ADAT to TDIF converter This unit allows ADAT format 8-channel signals to be converted into the TDIF format used by Tascam DA-88 machines and compatibles. It is a bidirectional, stand-alone unit with its own power supply, and may be used independently of the AD-1000. (FC-8 available 3rd quarter 1996.)

COMBINATION OPTIONS

The AD1K-ADT option provides UV22 Digital Through and 20-bit ADAT capability as described above. The AD1K-20FC option adds an FC-8 to provide all three platinum options described above. This option makes a standard AD-1000 equivalent to the AD-1000 Platinum Edition. AD-1000 Platinum Edition. This is an AD-1000 system ordered with all three platinum options listed above.
Specifications and features subject to change without notice. Apogee Electronics Corporation, 3145 Donald Douglas Loop South, Santa Monica, CA 90405, USA

AD-1000

Portable Reference Analog to Digital Conversion System Operating Manual and UV22 License Agreement
Revision 2.1: November 1996
AD-1000 Operating Manual Manual revised for this new edition by: Danny Buchanan, Caryn Perkins, Richard Elen, Johnny Story, Ryan Freeland and Bob Clearmountain.
SoftLimit is a Trademark, and UV22 is a Registered Trademark, of Apogee Electronics, Inc. All other trademarks are property of their respective holders. Technology within the AD-1000 including the C768 Low Jitter Clock is covered by one or more patents that are the property of Apogee Electronics Corporation. Registered User Customer Support: For customer support, please call (310) 915-1000 or email support@apogeedigital.com
Features and specifications subject to change without notice. 1996 APOGEE ELECTRONICS CORPORATION 3145 Donald Douglas Loop South Santa Monica California 90405 USA Tel: +1 310/915-1000 Fax: +1 310/391-6262 Email: info@apogeedigital.com Web: http://www.apogeedigital.com/ This manual is copyrighted 1996 by APOGEE ELECTRONICS CORPORATION, with all rights reserved. Under copyright laws, this manual may not be duplicated in whole or in part without the written consent of Apogee.

Part Number AD-1000MAN

Rev 2.0v1 August 1996
CAUTION Any changes or modifications not expressly approved by APOGEE ELECTRONICS CORPORATION could void your authority to operate this equipment under the FCC rules.

AD-1000 Operating Manual

The Apogee AD-bit Resolution A/D Converter
Your first class ticket from analog to digital!

A Note of Thanks

At Apogee we believe creating new products which really mean something requires putting a lot of ones self into that product. Apogees AD-1000 was conceived and designed with a passion. The team who put it together put themselves into the product and the results show. We wanted the very best performance and most flexible capabilities at a reasonable price. We took the pre-production units to the toughest critics, our friends in the mastering world, fussy mixing engineers, and picky end users. When we reached the point where they couldnt reliably pick between the analog original and the AD-1000 digital output, we knew we had arrived at our goal: a transparent, unveiled digital reflection of the analog source. Up to that point we tweaked and honed the design for almost two years, keeping you and our other clients waiting while the perfectionist in us wouldnt let go of the earlier designs. We know you will find the wait was worth it. Thanks for trusting Apogee we are sure your new AD1000 will surpass your expectations and provide years of quality service.
Apogee Electronics Corporation

Notes on CE Operation

In order to comply with the new (January 1996) requirements for electronic equipment operated in the European Union, Apogee converters must be equipped and operated with special adapters. These adapters are inserted into all of the I/O connectors on the converters and the normal cabling is then inserted into the adapters. Also, the equipment must be marked to reflect that it meets the CE standards (CE mark). The breakdown, by product, is as follows:
AD-1000 Special adapter kit CE-AD-1000 must be used for the I/O connectors. The connectors are labeled Left Input, Right Input, Digital Output, and Sync Input. The converter itself must be marked CE. DA-1000E-20 Special adapter kit CE-DA-1000 must be used for the I/O connectors. The connectors are labeled Left Output, Right Output, AES Input, and S/PDIF Input. The converter itself must be marked CE.
PS-1000E The power supply (PS-1000E) is internally modified and marked with CE. The cable for the power supply has also been internally modified and marked CE. This cable must be used to to meet the CE requirements.

Service Information

If the AD-1000 is kept in a clean environment free of excess dust, moisture and heat, it will give years of trouble-free service. The only components with a limited life are the electrolytic capacitors used. These are of high quality and will give many thousands of hours service. The AD-1000 contains no user-serviceable components: refer to qualified service personnel for repair or upgrade. Your warranty will be voided if you tamper with the internal components. If you have any question with regard to the above, please contact Apogee by phone at (310) 915-1000, by fax at (310) 391-6262, or via email to support@apogeedigital.com. In the event your AD-1000 needs to be upgraded or repaired, it is necessary to contact Apogee prior to shipping, and a Return Materials Authorization (RMA) number will be assigned. This number will serve as a reference for you and helps facilitate and expedite the return process. Apogee requires that shipments be pre-paid, and requests that all USA-originated returns be sent via UPS, and all international returns shipped via Federal Express unless otherwise authorized in advance. IMPORTANT: Any shipment that is not pre-paid or is sent without an RMA number will not be accepted.
AD-1000 Operating Manual THIS PAGE INTENTIONALLY LEFT BLANK

Table of Contents

An Introduction to the AD-1000....11 Introduction and Features....11 Specifications....14 Inputs.....15 Outputs.....16 Optional Accessories....17 Unpacking and Installation....18 Getting Started Quickly...19 A Quick Guide to using your AD-1000...19 Basic Operation....20 Front Panel Locations & Functions...20 Input Selection....20 Oscillator.....21 Metering.....21 Digital Inputs....22 Soft Limit Function and Calibration...23 Phantom Power....24 Output Resolution Selection and UV22...25 Timing and the AD-1000...25 Selecting the Internal Crystal Sync...25 Locking to External WORD SYNC Inputs...26 Locking to External AES Sync Inputs...26 Locking to External S/PDIF Sync Inputs...27 Locking to External Optical Sync Inputs...27 Video Sync.....27 Video Levels....28 Locking to a NTSC Video Sync Source...28 Locking to a PAL Video Sync Source...28 Locking to a Monochrome Sync Source...28 Output Format and Selection....28 Rear Panel Functions and Locations...30 Analog Input Connections....30 Digital Outputs.....30 Advanced Operation.....31 DIP Switches location and settings...31 Technical Input Information....32 Built in Level Calibration Using One LED....33 Digital Headroom Explained....33 Options and Enhancements....35 Digital Through with UV22 Processing...35 Using the AD-1000 with ADAT Systems...Bit Recording...37 AD-1000 ADAT Configurations...Bit Recording Option...38 Using the AD-1000 with DA-88 Systems and the FC-8...41 S/PDIF and Word Clock Output....43 Battery Operation.....43 Other 12 Volt Sources....43

Power Connector Pinout Diagrams...44 Appendix I: About UV22 Super CD Encoding...46 UV22 Caveats....49 Appendix II: About Digital Audio Interconnects...50 Revision History....55

Introduction

The AD-1000 is a multi-purpose stereo analog to digital converter combining a high quality dual-stage, triple servo, analog front end with 20 bit resolution. This combination provides unmatched sonic performance of 20 bit resolution, optimized for 20- and 16-bit applications such as digital tape recorders, disk-based audio workstations, and CD premastering. The AD-1000 includes Apogees UV22 Encoding system, as used by mastering facilities worldwide to capture 20 bit detail in 16-bit formats such as CD and DAT.

Analog Input Circuitry

The AD-1000 features a proprietary balanced discrete front end with a combined noise and distortion measurement in the 0.001% range. The unit features XLR input connectors that will accept input levels from microphones and line levels up to +28 dBu. The common mode rejection is typically 100 dB surpassing even the finest transformers and provides very stable performance over a broad temperature range. Also incorporated, in front of the active circuitry, is a passive RF filter with hand-selected resistors and capacitors matched to better than one part per thousand to roll off any outside interference, without the typical intermodulation distortion byproducts of active circuitry.
Input Selector and Gain Controls
The input selector is an 11-position switch providing maximum input flexibility. When the switch is in the center MUTE position, the digital output still delivers a digital black condition (all 0s) used for sync in many mastering and video applications. Rotating the selector clockwise, the next five positions select microphone input gain in 10 dB increments. Used in conjunction with the LEFT and RIGHT input level controls, up to 54 dB of gain is available (40 dB from the input selector and an additional 14 dB if the LEFT or RIGHT controls are fully clockwise). This combination allows the setting of the coarse gain with the input selector and fine calibration using the LEFT and RIGHT controls. (Note: The LEFT and RIGHT controls can be bypassed and the gain can be routed to the multi-turn CAL pots if desired. See page 31 for details of this procedure.)

It is unusual to use an analog to digital converter in a stand-alone environment. We have included every popular sync source capability via the ground-isolated BNC connectors (with additional loop through). Sync is selected via the front panel SYNC SOURCE SELECTOR SWITCH. Sync source capabilities include: CRYSTAL (selects the internal crystal reference from the sample rate switch); WORD CLOCK (locks to any external clock from 32 to 54KHz, including full vari-speed operation); AES/EBU, S/PDIF; VIDEO and SYNC (NTSC [525line/59.94Hz], Monochrome [525line/60Hz], PAL [625line/50Hz] are provided).

Sample Rate

An accurate 10 PPM internal crystal provides sample rates of 32, 44.1 and 48 KHz and the 0.1% derivatives 44.056, 44.144, 47.952 and 48.048 KHz (useful in film and video transfer work). The AD-1000 also has ability to multiply or divide incoming AES, S/PDIF, Optical and Word Clock sync by 1.001 for added flexibility. (1.001 is the ratio between monochrome video originally used in mastering CDs and NTSC video.)

Metering

A simple but very effective LED metering system has been incorporated into the AD-1000 that indicates levels below converter clipping and is designed to be used with the hosts metering. The 12 LED for each channel can be customized. The 12 labeling is nominal; in fact the threshold of this LED is tied to the digital oscillator level and can be varied from 20 to 12 below 0dBfs. This is done by adjusting various switches on the top of the AD-1000. The 12/Threshold LEDs also serve an additional function. When a signal is within 0.05dB of the nominal gain of the AD-1000 oscillator setting, these LEDs flash rapidly. This is used to calibrate the analog to digital conversion levels. For additional information, see Section 6, page 33. When Soft Limit is engaged, the 2 LED acts as a Soft Limit Threshold indicator. When this threshold is achieved, the 2/SL will light. When Soft Limit is not engaged, the LED will signal when a peak of 2dBfs is achieved. Two separate Red LEDs indicate overs (digital clipping) when three or more samples in a row reach all ones.

Digital Outputs

A separate transformer-isolated AES/EBU output is provided on the rear of the unit. Also provided is a fiber optic output connector which can supply either TOSLINK or ADAT format. S/PDIF and WORD CLOCK outputs are available on a high density 15-pin HD connector. (SDIF outputs are also optionally available on this connector). Additionally, the WORD CLOCK output is driven by the internal Low Jitter Clock via a high speed optoisolated driver.

Page 12

The C768 Ultra Low Jitter Slaving Clock references to an external clock source and provides a flywheel effect by smoothing out short-term timing irregularities or jitter. This low jitter slaving clock locks in a predictable and very accurate phase relationship with the incoming reference. The result is superior sonic imaging with excellent soundstage detail. Whenever possible, the AD-1000 should be the digital timing source for the digital studio. Additional information on the sync capabilities of the AD-1000 is included on page 25 of this manual.

Apogee Patented Low Jitter Clock

Page 13

Specifications
QUANTIZATION FREQUENCY RESPONSE TOTAL HARMONIC DISTORTION PLUS NOISE (THD+N) Full Amplitude 20dB scaled to Fs SIGNAL TO NOISE RATIO CROSSTALK SOFT LIMIT THRESHOLD METERING THRESHOLDS 20 Bits/Sample 20Hz10KHz 0.025dB 10KHz20KHz +0.025 / 0.1dB
Typically 100dB @ 48KHZ sampling; 0.5dB below full scale Typically 103dB@ 48KHZ sampling; 0.5dB below full scale
Typically 104 Unweighted, 109dB A weighted Typically better than 110dB @ 1kHz 1.5dB below digital output full scale (adjustable) selectable on/off Amber indicates 2dB below full scale (includes peak hold function and SoftLimit Threshold) Green indicates 12dB below full scale (adjustable) (includes peak hold function) Red indicates three overs in a row (Includes peak hold function) COMMON MODE REJECTION Typically better than 110dB@100Hz Typically better than 75dB @10KHz EXTERNAL SAMPLING RATE RANGE Any frequency from 32KHz to 54KHz via External Sync Input INTERNAL SAMPLING RATE 32kHz, 44.056kHz, 44.1kHz, 44.144kHz, 47.952 kHz, 48kHz or 48.048kHz SAMPLING RATE ACCURACY 10 PPM SAMPLING RATE INDICATOR Amber LEDs indicate output sampling rate range for 32KHz, 44KHz, and 48KHz INTERNAL CLOCK JITTER Typically 30 picoseconds RMS NOMINAL DC POWER INPUT 12vdc @ 1150-1300mA dependent upon function INPUT VOLTAGE RANGE +11.5 to +15 Volts DC (well regulated) INPUT DROPOUT VOLTAGE 10.4 Volts DC LOW VOLTAGE INDICATOR Power LED Flashes at <11.5vdc Power Input WEIGHT 1.3Kg (2 lbs 14 oz) DIMENSIONS L=273.0 x W=141.2 x H=39.6 mm (L=10.75 x W=5.56 x H=1.56 in) OPERATING TEMPERATURE 0C to 40C (32F to 104F)
15-pin HD connector: Power (+12vdc) Word Clock out S/PDIF out SDIF out 256 Fs out
Analog In Left XLR Female Analog In Right XLR Female AES/EBU Out XLR Male
BNC Sync In S/PDIF Out S/PDIF + ADAT TOSLink Optical & Digital Ins*
*Word Clock, video; AES sync, S/PDIF sync; AES Audio, S/PDIF Audio. Both connectors tied together (loop through) Unused connector should be terminated.

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AD-1000 Operating Manual Note: The AD-1000 will work with any well regulated 12V DC Power source with an output current of 1300 mA or greater. We recommend using linear type power supplies Direct connection to external 12VDC lead acid or NiCad batteries will provide convenient portable operation. See page 43 for additional details on battery power.

Page 19

Operation
Locations and Functions: Front Panel Controls
The AD-1000 offers an input section that can receive a wide variety of Analog and Digital inputs ranging from low microphone levels to the hottest line levels. The controls affecting the audio input selection and level are located toward the left of the unit and are detailed above. AES, S/PDIF electrical and optical signals can also be input and reformatted to other digital output types.

Input Selector

The input selector is an eleven position switch providing a wide selection of options, as follows:
When the analog input selector is switched to MUTE, the outputs of the AD-1000 transmit what is known as audio black in their respective digital formats. This is a signal which corresponds to zero level input. Word Clock is still available at the 15 pin HD connector on rear panel. The analog to digital converter is turned off and will not pass audio; the analog and digital sections of the converter are powered down. The second MUTE position located at the 8 oclock position is the same in function to MUTE at the twelve oclock position except that phantom power is turned off in the 8 oclock position.
MIC Input 0, 10, 20 ,30 ,40
Rotating the selector clockwise, these five positions select microphone input gain in 10 dB increments. Used in conjunction with the LEFT and RIGHT input level controls, up to 54 dB of gain is available. (40 dB from the input selector and an additional 14 dB if the LEFT or RIGHT controls are fully clockwise.) This combination allows the setting of the coarse gain with the input selector and use the LEFT and RIGHT controls for precise control. The LEFT and RIGHT rotary controls can be bypassed and the gain controlled by the multi-turn CAL pots if desired. This is accomplished by changing the DIP switch settings accessed via a slot on top of the AD-1000.

Line Level Input +4, 10

Two CAL positions are available by rotating the INPUT SELECTOR counter-clockwise from twelve oclock. These CAL positions correspond to a nominal +4 (Pro) and nominal 10 (Consumer) line level inputs. When either of these positions are selected, the multi-turn CAL trim pots located to each side of the INPUT selector are enabled. These multi-turn pots are adjustable by a small straight blade screw driver. The CAL pots can be bypassed and the gain controlled by the LEFT and RIGHT rotary controls if desired. This is accomplished by changing the DIP switch settings accessed via a slot on top of the AD-1000. Refer to page 31 for further information.

AES Sync Inputs

Selecting the AES sync source positions enables the AD-1000 to lock to any AES/EBU digital audio source. The AES/EBU Sync Source is input via the BNC connector. No audio information is transferred unless a digital input is selected. The sync information is extracted from the AES/EBU data stream. Two AES positions are available. The position labeled 110 AES terminates the input with a 110 impedance. You would use the Terminated position if the AD-1000 was the last or the only device in the AES chain. The position with the ( ) above it signifies a bridged input of 5k for the AES. This position would be used if the AD-1000 was not the last device in the chain. Depending on the input sampling rate, the appropriate LED will illuminate to indicate lock. The SAMPLE RATE Selector should be in the 6 oclock position. In this sync source mode, the AD-1000 normally outputs the same frequency as the AES Signal connected to the Sync Input. Two other positions of the SAMPLE RATE Selector provide the unique ability to increase the input sampling rate by a 1.001 ratio. See the earlier section on PullUp and Pull-Down for details.
Selecting the S/PDIF sync source position enables the AD-1000 to lock to S/PDIF digital audio sources. No audio information is transferred unless the input selector is set to Digital. The sync information is extracted from the S/PDIF data stream. Apply the S/PDIF input signal to the BNC. If you are not looping signal through to another unit, terminate the signal by selecting the correct switch setting on the 8 position DIP switch located on the top of the AD-1000. Additional details are on page 31. If looping the signal to other devices, the last unit in the chain should be terminated with 75.

S/PDIF Sync Input

Page 26
AD-1000 Operating Manual The SAMPLE RATE Selector should be in the 6 oclock straight down position. In this sync source mode, the AD-1000 normally outputs the same frequency as the S/PDIF signal connected to the Sync Input. Two other positions of the SAMPLE RATE Selector provide the unique ability to increase the input sampling rate by a 1.001 ratio.

Optical Sync Input

The optical sync source comes in via the optical cable input connector located on the rear panel. If the power switch is in the NORM position, then this sync input acts in the same way as the S/PDIF or AES inputs do. If the AD-1000 is selected to ADAT then the incoming signal is expected to be from an ADAT optical output. ADAT input is only possible if the special AD1K-PRT option is installed. The SAMPLE RATE Selector should be in the 6 oclock position. In this sync source mode, the AD-1000 normally outputs the same frequency as the ADAT signal connected to the Optical Input. Two other positions of the SAMPLE RATE Selector provide the unique ability to increase the input sampling rate by a 1.001 ratio.

Input Impedance

Balanced or Unbalanced Inputs
The AD-1000 input will accept both balanced and unbalanced inputs. No internal jumper selectors are required. The maximum input level is +28 dBu balanced and +24 dBu unbalanced. This is the level which will produce a full scale digital output with the multi-turn CAL pots in their minimum position.

DC Removal

The input to the AD-1000 is direct coupled in the Line +4 and 10 CAL positions: no capacitors are in the signal path. This means the DC inputs will be passed through the direct coupled stages all the way to the conversion stage. The AD-1000 has very effective DC servos to remove both common mode and differential DC inputs well beyond the specified 50mV DC common mode and 50mV differential. The servos remove any residual DC from the digital output to beyond the 16th LSB level to deliver a totally centered digital output. This eliminates the need with most converters to trim for DC removal or run through an external high pass filter which, more often than not, compromises the sonic integrity of the analog input. The Apogee approach goes back to basics for a simple method of extracting DC without the attendant number-crunching of a digital high pass filter.

Common Mode Rejection

Common Mode Rejection is a measure of how well an input ignores interference picked up on pin 2 and 3 together. The AD-1000 discrete input stage features excellent common mode rejection. With a well-balanced input, the common mode rejection at 100 Hz is typically better than 110 dB and at 10 KHz is typically better than 80 dB. (Reference Settings: +15 dBu input signal and 0.5dB f.s. digital audio output.) This common mode performance assures quiet performance in the presence of external noise and interference.
Total Harmonic Distortion and Noise
Technically, analog circuitry is often judged by how little distortion and noise it adds to an input. In reality, this is a good indication, but not the entire story. At Apogee, we trust listening tests over measurement. The AD1000 gives the best of both worlds: it sounds great and measures great! The entire analog section of the AD1000 typically has total harmonic distortion plus noise performance better than 0.001% with Soft Limit switched out. (Soft Limit only affects the distortion over the last 2dB.) REAR PANEL

Chassis Grounding

A switch located on the top rear of the AD-1000 allows the chassis and audio grounds to be connected together. The default position is pointing toward the front of the unit, which isolates the chassis and audio grounds. If you want the grounds connected to remove a grounding difficulty, moving the switch to the back position will accomplish this. An LED will light to indicate that you are operating in a non-standard mode.
LED GROUND CONNECTED (LED lights) GROUND ISOLATED (Normal)

Location of Ground Lift Switch

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Precise Calibration using One LED
When you need to make a mix from your analog mixing console, it is necessary to calibrate your AD-1000 to the output of the mixing console. The AD-1000 incorporates a unique feature to enable you to simply match the digital output to within a hair width of your consoles meters. The 12 LED is much more flexible than the labeling would make it appear. When you input an analog signal into the AD-1000, the 12 LEDs threshold becomes variable and coincides with the headroom setting of the digital oscillator. This permits precise matching of an analog input to the internal digital oscillator. If the internal digital oscillator is set to the default 15dBfs position (all three switches in default off) the 12 LED will remain off until the input level reaches 15dB (Peak) below full scale digital output. Passing the threshold turns the LED On. In addition, the LED will blink rapidly to tell you when the signal is within the 0.05dB of the 15dB threshold. If you are inputing a calibrated analog sine wave oscillator tone from your console (typically +4dBu for an analog meter zero) you can now adjust the selected gain pots on the AD1000 to make the 12 LED blink. You have now calibrated the AD-1000 to within 0.05dB of the perfect digital oscillator. Switching between the analog input (such as +4) and the digital oscillator will show perfect calibration. The calibrated headroom can be varied to best suit your application by changing the digital oscillator headroom. The blinking point for the 12 LED moves right along with it. The mastering world usually chooses 12 or 14dB, tracking tends to be done with 15 to 8 dB and the film world tends to play it safe with up to 20dB of headroom.
(See diagrams overleaf.) A hotter-sounding compact disc can be the difference between having a hit or being forgotten. A hotter-sounding CD means not wasting headroom. In analog recording we define a nominal operating level and allow enough headroom above to avoid clipping the analog circuitry. This nominal level is usually referred to as zero for the 0dB calibration on analog meters. The analog zero usually represents a nominal +4 dBu output level, i.e. when the meter indicates 0 it is really putting out a level of +4 dBu. With digital audio, the precise distortion or clipping point is known. This is the point where we run out of numbers to represent the analog input. This maximum positive (or negative) level is often called an over due to the popular labeling of digital meters. The over indicators illuminate when a digital maximum is reached, usually for a total of more than 3 samples in a row. NOTE: Some DAT recorders such as the Panasonic 3700 and 3900, indicate overs with analog inputs, but do not indicate them with digital inputs such as from the AD-1000. In digital audio we must decide on how much headroom we want above our nominal level (the zero from analog world) before we hit an over or digital clip. The aim is to use as much of the dynamic range as possible. Any wasted headroom means we are closer to the noise floor than necessary. We require more or less headroom, depending on the material being recorded. Mastering engineers typically choose 12 or 14 dB headroom over their nominal input level because they usually have their dynamics tightly controlled. In tracking situations, 15 and 16 dB are the most popular, with some users going as high as 18 and 20 dB. The headroom of analog inputs or some DAT recorders are often fixed, such as at 18 dB for the Panasonic 3700 and 3900. When using the AD-1000, the headroom is easily adjusted with the front panel controls (purple knobs essential for high-quality digital audio) or front panel multiturn pots, and the built in oscillator for generating the a digital test tone at a known digital level and using the precise threshold to input tones and adjust the gain pot or CAL pot. Digital audio levels are often referred to the maximum level (or full scale, f.s.). Zero dB full scale is a maximum level when referring to digital levels. With 16dB headroom, the nominal level would be then sitting down at 16dB referenced to full scale (f.s.)

Headroom

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Digital Headroom Explained
ANALOG METER MAX. ANALOG +19dBu LEVEL +19 dBu with +4dBu @ 0 ref

15 dB HEADROOM

DIGITAL OUTPUT
AD-1000 LEDs 0 dB Full Scale -2/SL dB LED ON*

'-12' dB ON

ANALOG NOMINAL +4dBu TYPICALLY 0dB

+.05dB

'-12' dB LED Blinks '-12' dB OFF
COMPARISON OF ANALOG INPUT TO DIGITAL OUTPUT WITH 15dB HEADROOM AND +4 dBu REFERENCE ANALOG METER MAX. ANALOG +17dBu LEVEL +17 dBu with +4dBu @ 0 ref

12 dB HEADROOM

AD-1000 LED's 0 dB Full Scale -2/SL dB LED ON*
COMPARISON OF ANALOG INPUT TO DIGITAL OUTPUT WITH 12dB HEADROOM AND +4 dBu REFERENCE ANALOG METER MAX. ANALOG +24dBu LEVEL +24 dBu with +4dBu @ 0 ref

20 dB HEADROOM

COMPARISON OF ANALOG INPUT TO DIGITAL OUTPUT WITH 20dB HEADROOM AND +4 dBu REFERENCE *Dependent upon SoftLimit Threshold and activity.

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Options and Enhancements
AD1000 UV22 Digital Through Option
The UV22 digital through option gives the AD-1000 the ability to process digital input signals with Apogees award-winning UV22 encoding technique, which preserves the audio quality of 20-bit signals in a 16-bit environment. (The standard AD-1000 includes UV22 encoding, but only on analog input signals. Digital signals may be format-converted but not encoded in the standard model.) This option allows a studio to work entirely at 20-bit resolution and then run the completed project through the AD-1000 to apply UV22 encoding down to 16-bits. Operation: 1. Connect your digital audio source to the AD-1000 to the top BNC port on the back of the AD-1000 for AES/EBU* or S/PDIF operation. Optical input is available via the TosLink connector on the back of the AD-1000. * NOTE: A special cable (Apogee part # WE-BX-0.5FT) is required to interface an AES/EBU XLR cable to the BNC port. 2. Set the INPUT SELECTOR to the DIG position. 3. Set the SYNC SOURCE to 110 AES, S/PDIF, or OPT. (depending on type of digital audio source.) NOTES: S/PDIF must be terminated with 75 by selecting the DIP switch 1 to ON (located on top of the AD-1000). Alternatively, a 75 BNC termination (supplied with the AD-1000) can be connected to the unused BNC connector. Termination is not necessary if looping to another device, as the last device in the chain is then terminated. Two AES positions are available. The position labeled 110 AES terminates the input with a 110 impedance. The AES position with the ^ above it signifies a bridged input of 5 k for the AES. This position would be used if the AD-1000 was not the last device in the chain.

ADAT w/Multiple AD-1000s

(Two channels per ADAT)
Video Sync Generator 75 Coax 75 Coax Video In Optical Out Fiber-Optic Cable AD-1000 Sync Source: NTSC Sample rate: 44.1, 48 kHz Termination: Bridge BRC: Ext Sync Video

ADAT w/VIDEO SYNC

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AD-1000 Operating Manual Recording To record a true 20 bit signal onto an ADAT recorder (which is a 16-bit recorder) the following steps must be taken: 1. Connect optical cable from AD-1000 optical output to the optical input of the destination ADAT. Set ADAT to digital input. Note: the optical cables cannot be looped thru ie, multiple input to output connections made as in digital track- bouncing mode. Only connect between AD-1000 and the machine to be recorded on to. 2. Select any analog input (+4, 10 or mic pre) or the oscillator. 3. Select the appropriate sync source (crystal, WC, video, etc.). 4. The 16 / UV16 / 20 switch should be set to 20 (20-bit output). 5. Select the sample rate of choice. Please note that ADAT will only accept either 44.1 kHz or 48 kHz, so if you select any variation of 44.1 kHz (44.056 or 44.144) you will still only get 44.1. Likewise with 48 kHz selecting any of 47.952, 48, or 48.048 will get you only 48 kHz! Also note that when using an external sync source (WC, video, AES, etc.) the gear box function (x1.001 or 1.001) does not operate. Further note that when referenced to NTSC video, both sample rates will be pulled down to either 44.056kHz or 47.952kHz. 6. Lastly, the power switch must be switched to the ADAT position to the right, opposite of NORM. 7. Eight channels of information will be transmitted (two stereo pairs): you will need to select four adjacent tracks, either 1 thru 4 or 5 thru 8, to be able to properly decode this information for playback. Playback To play back this special signal format, it must first be recombined into a normal 20-bit signal (AES or S/PDIF). It can then be UV22d to a CD recorder or converted to analog by one of our DA-1000E-20 digital to analog converters. 1. Connect an optical cable from the ADAT output to the AD-1000 optical input. Please see above note about looping. 2. Select DIG (digital input) on the Input Selector Switch. 3. Select OPT (optical) on the Sync Source Switch. 4. The 16 / UV16 / 20 switch will select the level of resolution at either the AES or S/PDIF (optical) outputs. Note that in this mode the optical output is in the S/PDIF format, not ADAT. 5. The power switch should be selected to ADAT. 6. The Sample Rate switch now determines which of the eight tracks are received and in what form. The following chart shows the various possible combinations. Sample Rate Switch Position 1 oclock (47.952) 2 oclock (48) 3 oclock (48.048) 4 oclock (x1.001) 5 oclock (unmarked) 6 oclock (unmarked) Track 1&2 3&4 5&6 7&8 Format 16 bit 4 bit 16 bit 4 bit 16 bit 4 bit 16 bit 4 bit 20 bit 20 bit 20 bit 20 bit Channel A B A B A B A B A B A B

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AD-1000 Operating Manual UV22 rounds out the rough edges of digital Stephen Marcussen, Precision Mastering, Hollywood [The Apogee UV22] rounds out the rough edges of digital. I put material through the UV22 at below 60 dB and you could clearly hear the low-level information. It was much smoother and much more intact. The low-level stuff was really nice and smooth. The signal with the UV22 was a lot clearer than without.
The Apogee UV22 is an excellent way to utilize 20-bit A/D conversion and 20-bit signal processing. It allows you to capture the improvements of 20-bit even on 16-bit formats. Most importantly, it is very musical sounding; it doesnt change the tonal balance. With the UV22 the 16-bit output sounds very close to the 20-bit source. Its simple to use and sounds great. Bravo! Scott Hull, Masterdisk Corporation, New York When a 20-bit signal is processed by the UV22, the result is essentially the same as the 20-bit original, and cleaner than Turbo Bit Mapping. John Newton, Sound Mirror, Jamaica Plain, MA

UV22 Process Caveats

UV22 Encoding is expected to be the final step in the signal chain before the CD mastering device such as the Sony 1630, etc. No additional process of any kind should be performed on the UV22 processed data or the benefits may be compromised. Other points in the signal chain are possible, but some care must be taken when applying the process. Because of the addition of the UV22 signal, it is not recommended to use the UV22 process more than once or twice on a signal. Multiple passes through the UV22 process could degrade the noise floor of the system in the upper frequencies. Experimentation with the Normal and Low settings is recommended for multiple passes. In the Normal mode, the process has been optimized to capture the greatest amount of detail from the high resolution digital input. The Normal mode has the added benefit of smoothing out the non-linearity in almost any DAC. Even with 16bit sources, the UV22 process gives notably better results on inexpensive DACs. By using the Low setting, less of the detail is captured. The Low setting maintains respectable performance with a reduction in the UV22 Energy Clump of 6 dB. The reduction in energy could be desirable when multiple passes on a signal are performed. Recordings to be used in a Sample or Sound Effects Disc can be encoded if only pitch shifting upward is to be used. Pitch shifting downward on processed signals could make the UV22 Energy Clump audible. At this time we do not recommend UV22 processing on signals that are destined for compression systems such as the Sony MiniDisc format. The UV22 Process encodes so much detail that it is possible that the compression algorithms could have adverse effects on UV22 processed material. For this reason, the intricate information captured by the UV22 process would complicate the lives of MD compression systems. We have not done extensive listening tests on this yet, but do advise caution. This caveat is not only true for the UV22 process but for noise- shaping systems such as Sonys Super Bit Mapping.

All At Once or A Bit At A Time
A drummers timing can make the difference between good music and a memorable hit. Digital audio, likewise, needs good timing to make it from one place to another with uncompromised sound quality. The timing in the interconnect is used to unscramble all the bits for accurate recovery of the exact samples transmitted. The timing also needs to be very regular. Timing jitter is any irregularity in the timing passed across an interconnect. If the samples become messed up in the interconnect, the effects are usually very audible, varying from occasional clicks to a loud, harsh fuzz. Timing jitter can cause more subtle effects. In digital to analog converters for example, the location of instruments across the audio sound stage can become less focused. Note: A sound stage is the mental picture you form when you listen to a piece of music and localize the various instruments and vocals as if they were on stage in front of you (closing your eyes can help form the image). A well defined sound stage has width, depth, and focused locations all defined by subtle reflections, reverb tails and tonal quality in a stereo mix.

Its All In The Timing

You may have heard critical digital audio listeners complain if digital audio is so perfect, then how come it sounds different when I use different interconnects? Some experts will tell them it must be their imagination because if the numbers are sent correctly on each interconnect they both must sound the same. That makes sense, but its only part of the story When a digital to analog converter receives the samples from an interconnect, it must also extract the timing information and regenerate its own timing clock. A good analogy is a drummer playing to a click track. If the drummer is good, he can nail the basic tempo of the click and add in faster patterns of his own, such as a sixteenth-note high hat. When digital devices receive the clock from an interconnect, they lock up to the sample
These Interconnects Sound Different!

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AD-1000 Operating Manual rate tempo and add faster multiples many times higher than the drummers sixteenth-note example. Now imagine what would happen to the drummers playing if we put slight, random variations in his click track reference. The drummer would try to follow the changing tempo but because the changes were unpredictable, he would overshoot the click tempo as it moved up and down. The random click track variations around a perfectly steady tempo could be called tempo jitter. The poor drummer ends up with worse jitter in his timing unless he can ignore the small changes and play to the average. The problem of interconnects affecting the sound can be traced to jitter in the timing of the digital to analog playback. Each time digital audio timing is passed through additional circuits, it picks up slight variations around the original perfect timing. The amount of timing jitter added through successive stages depends on the type of circuits. Inside products, different computer logic families used for digital calculations add varying amounts of jitter. Noise on power supplies and grounds, nearby clocks with similar harmonics, AC power and external interference can all add jitter to perfect timing. Some of it is random and some has specific frequency content. When the internal timing is passed to another device over an interconnect, different types of connections add more or less jitter. A short AES/EBU connection over high quality digital audio cable such as Apogees Wyde Eye 110 AES/EBU cable will pick up less jitter than the same signal run through a length of microphone cable, XLR connectors and patch bays. A S/PDIF coaxial wire connection (especially one made with Wyde Eye 75 cable) will be cleaner than the consumer TOSLINK optical version, at least partially because of the slower response time of the optical transmitter and receiver. When the circuits in digital to analog converters (D/As) recover the timing, they are often negatively influenced by the jitter picked up along the way, much like our miserable drummer trying to follow the varying click track. When the recovered timing starts to wobble around as it tries to track the jittery input, it modulates the analog sound coming out of D/As, causing all sorts of subtle negative effects such as changes in the stereo image and tonal quality. An interesting source of jitter in AES/EBU digital interconnects is due to the changing samples and subcode information. A 1kHz digital audio tone causes 1kHz jitter. Different interconnects do not sound different if the timing circuits of the reference D/A are designed to ignore any jitter and the samples are correctly transmitted. Manufacturers can claim low jitter circuitry although its only a relative claim, as at the moment there are no accepted standards for jitter measurement for digital audio. Jitter also has a big influence on the quality of analog to digital converters with very similar side effects, which unfortunately are there forever after.