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

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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.)
Line Level Inputs +4 dBu and 10 dBV
Two CAL positions are available by rotating the INPUT SELECTOR counter-clockwise from twelve oclock. These positions correspond to +4 (Pro) and 10 (Consumer) line level inputs. When either of these positions are selected, the multi-turn CAL trim pots are enabled. (Note: The CAL pots can be bypassed and the gain can be routed to LEFT and RIGHT controls if desired. See page 31 for details regarding this procedure.) 48 volt phantom power is supplied to both microphone inputs when this selector is in the ON position and the input selector is in any MIC or the 12 oclock mute position. The phantom voltage ramps up and down slowly for quiet activation and uses highly accurate resistors for optimum performance.

Phantom Power

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Soft Limit

Included with the AD-1000 is Apogees highly acclaimed Soft Limit circuitry. (This feature has functioned as many an engineers secret weapon to get extra level in their masters.) Soft Limit functions as a selective peak limiter. Typical peak limiters are very abrupt and can spread unwanted harmonics. With the AD-1000, once an input signal passes the threshold, Soft Limit gently removes the peaks by rounding them off, making the limiting action very difficult to hear. The result is hotter sounding program material.

Filters

Apogee has long been known for filter technology the result of years of proven, proprietary designs. The AD1000 continues this tradition with the ultimate in filter performance. A quadruple stage, progressive passive filter is inserted between the analog inputs and the analog to digital converter. The AD-1000 resolves analog detail to the 20-bit level to capture accurately every subtle nuance of the analog input signal. The output can be either 20-bit resolution or 16-bit. Apogees UV22 Super CD Encoding system may be utilized when working with 16-bit recording formats. Used by virtually all major mastering facilities, UV22 captures the resolution and detail of the 20-bit conversion in a 16-bit word length; information that would normally be lost.
20 Bit Conversion and UV22

Sync Sources

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.

Level Below dB Full Scale 0 Audio Black*
Switch 2 Off Off On Off On On On Off
Switch 3 On On Off Off Off On On Off
Switch 4 Off On Off Off On Off On On
LED Display Left 12 (green) Left 2 (amber) Left Over (red) Right Over (red) Right 12 (amber) Right 2 (green) All On All Off
*Audio Black is defined as a signal that contains clock data but no audio data (0 bits). The front panel metering LEDs indicate when the AD-1000 input signals are peaking in a comfortable range. They are designed to be used in conjunction with the meters of the host system such as a DAT recorder, workstation, etc. The GREEN 12 LED indication for each channel may be customized. The 12 labeling is nominal because 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 AMBER 2 /SL LED indicates when the input signal is 2 dB below full scale digital out. When Soft Limit is engaged, it will also flash when the Soft Limit Threshold has been exceeded. The RED OVER LEDs illuminate when three consecutive digital Over samples are output. The AD-1000 also includes a unique feature for precise input calibration delivering accuracy unavailable with normal digital bar graph meters of DAT recorders and workstations. Only with digital meters costing as much as the AD-1000 itself can you approach the accuracy of this system. In conjunction with the Digital Oscillator settings, the 12 LED will flash quickly when a tone is connected to the analog inputs and is within 0.05 dB of the oscillator level set on the programming DIP switches, located on the top panels of the AD-1000. (Section 5, page 31 has more information regarding these switches and the procedure to complete the calibration of your system.)

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The last position counter-clockwise is the DIG position. When selected, an AES or S/PDIF signal (input via the top BNC connector on the back of the AD-1000) or S/PDIF optical signal (via the Toslink input connector) can be re-clocked and formatted into various digital outputs. This allows AES or S/PDIF conversion to ADAT and other useful format conversions. In this mode, the SAMPLE RATE cannot be selected and must remain in the 6 oclock position. The sample rate of the digital output will be identical to the input, within a range of 32kHz to 54kHz. The format of the input is selected by the SYNC SOURCE selector. AES, Terminated and Bridged, as well as S/PDIF coaxial, terminated and bridged and Optical are supported. ADAT can also be reformatted and selected when the Hi-Resolution Option (AD1K-PRT) is installed. See the Options & Enhancements section for further information on these options.

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Soft Limit Function
Evolved from the legendary AD500E, this unique Apogee feature makes your mixes jump out in the highly competitive market for CD airplay. Short transients can clip analog to digital converters and can produce unwanted harmonics. Typical peak limiters used to remove short transients are very abrupt and actually spread unwanted harmonics. If these short transients are removed without hard clipping, the average recording level can be raised by several dB with little or no sonic penalty (ie your ear doesnt miss the short transients if you remove them cleanly and dont overdo it).
Short transients that would normally cause overs are controlled with a gentle rounding with Soft Limit PEAK WITH NO SOFT LIMIT
Soft Limit does not make a hard, sharpedge clip as you would get if the converter was overdriven. Instead, once you pass the threshold, it rounds off any peaks in a manner that makes their removal difficult to hear. These sharp peaks do not usually affect the sound quality if they are cleanly removed. Also, you get none of the typical limiter/compressor byproducts such as pumping and breathing. Depending on the material being recorded, the threshold of audibility will vary. This is best found by experimentation. Just a few dB increase in average level can result in more powerful, hotter sounding CDs without fear of leaving a trail of overs.
LAST 2dB SAME PEAK WITH SOFT LIMIT FULL LEVEL OUTPUT SWING LAST 2dB TRANSIENT 810dB OVER MAX INPUT LEVEL THE EFFECTS OF SOFT LIMIT
EXPANDED PEAK SOFT LIMIT OFF CONVERTER CLIP (in bold) 'OVER' Signals under 2dB are not affected by Soft Limit
The Soft Limit feature of the AD-1000, unlike conventional peak limiters, does not have a precise kick-in point. It is, in fact a logarithmic curve whose steepness increases as you approach the threshold (therefore threshold is a misnomer.) Determining the amount of limiting or increased effective headroom you wish to attain is really best done by ear. However, you may find the following procedure a good reference point, or a way to check left/right symmetry once youve found a pleasing threshold by ear. Two different methods of calibration are described. One is for calibration with a recording console and the other is for calibration with test bench gear.
Soft Limit Calibration Procedure using a recording console

Timing and the AD-1000

Selecting Sync Source and Sampling Rate
When recording digitally, it is necessary to select an appropriate sample rate either independent of other equipment or locked to an external reference. The AD-1000 is very flexible, with very accurate internally-generated sampling rates and its ability to lock to a wide range of external sync sources. The AD-1000 can also act as a stand-alone sync generator.

Internal Crystal Sync

A crystal is a thin piece of quartz cut very precisely to vibrate at a very accurate frequency in an electrical circuit. The crystal inside the AD-1000 vibrates within plus or minus ten parts in a million (PPM) of the specified frequency. This translates to less than 0.5 Hz error at 44.1kHz which is equivalent to less than one-fiftieth of a cent at A440. When the sync source is set to crystal (o), the sample rate switch is active in any of the sample rate positions marked with a solid dot (). Illumination of the appropriate sample rate LED indicates lock.
Locking to External Word Sync Inputs
The AD-1000 locks to external word sync inputs (also known as Word Clock or WC). In this sync source mode the AD-1000 normally outputs the same frequency as the Word Clock connected to the Sync Input. Termination can be applied using the 75 terminator supplied with the AD-1000 and applied to the unused BNC connector. The AD-1000 SAMPLE RATE selector should be in the unmarked position (6 oclock straight down).

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Pull-Up and Pull-Down Sync
Two other positions of the SAMPLE RATE Selector provide the unique ability to increase or decrease the input sampling rate by a 1.001 ratio. Utilizing the above settings, any WC (Word Clock/Sync) input will be multiplied or divided by 1.001. For example a 44.056 kHz WC input will deliver 44.1 kHz locked to the input. Illumination of the 44 LED indicates lock. Users tell us this feature has saved the day in situations where the wrong sample rate was used. The x1.001 and 1.001 positions are marked with a square (s) which corresponds to the square on the WC, AES, OPT AND S/P DIF sync source positions. 1.001 is the ratio between the frequency of a NTSC color signal and the original monochrome standard. When engineers in the USA first developed the NTSC color television system, they found interference problems using the same frequencies as the monochrome system they were replacing. The solution was to slightly shift the color video frequency by 0.1% thus the 1.001 ratio. When Compact Discs (CDs) were developed, a reliable method to store the digital audio data in preparation for making the CD was necessary. The solution was to use a video cassette recorder to store the wide bandwidth information. A sampling rate of 44.1 kHz was chosen to pack the digital audio data conveniently on a U-matic video cassette in the form of a video signal. The video signal chosen was the NTSC monochrome standard of 525 lines/60 frames per second (525/60). This CD 44.1 kHz sampling rate is not compatible with a NTSC color video signal (525/59.94 Hz). In fact, 44.1kHz is 1.001 times higher than the 44.056 sampling rate that would be compatible with NTSC video. Therefore to lock a 44.1kHz sampling rate to NTSC video requires multiplying the NTSC reference by 1.001. Digital video machines (D-1, D-2) use 48 kHz sampling locked to NTSC video or PAL video. F-1 type systems use 44.056 Hz sampling in NTSC versions and 44.1 kHz sampling in PAL versions. As an example where you would need to use 1.001: in a music video application, a picture running at 59.94 FPS has to sync with a CD sound track running at 60 FPS (44.1 kHz sampling rate).

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

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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.

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Connect the video reference to one of the BNC connectors on the rear panel. Termination is not necessary if looping to another device and the last device in the chain is terminated with 75. NOTE: The video must be correctly terminated for proper AD-1000 sync operation. 75 termination is available by switching a DIP switch on the top of the AD-1000. Select switch position 1 to ON for 75 termination. (Additional information on this switch is available on page 31.) Alternatively, a 75 BNC termination can be connected to the unused BNC connector. Select NTSC video on the sync source selector and choose the sample rate with the sample rate selector. Illumination of the appropriate sample rate LED indicates sample rate lock to the external video source. Connect the video reference to one of the BNC connectors on the rear panel. Termination is not necessary if looping to another device and the last device in the chain is terminated with 75. NOTE: The video must be correctly terminated for proper AD-1000 sync operation. 75 termination is available by switching a DIP switch on the top of the AD-1000. Select switch position 1 to ON for 75 termination. (Additional information on this switch is available on page 31.) Select PAL on the sync source selector and choose the sample rate with the sample rate selector. Illumination of the appropriate sample rate LED indicates sample rate lock to the external video source.
Locking to an NTSC Video Sync Source
Locking to a PAL Video Sync Source
Locking to a 60 Hz Video Source (used in CD premastering)
The AD-1000 has two additional sync source selector positions. These two positions generate the seven output sampling rates from a monochrome video sync source. Monochrome refers to 525 line/60 Hz video. These sync sources can also be used with NTSC video when the need to bump-up or bump-down is required. The effect will be the same as using the 1.001 positions with a monochrome sync signal. Opposite is a matrix that summarizes all of the possible sync combinations. Those combinations that are illegal, such as 48.048 locked to NTSC will blink the three sample rate indicators to indicate an error in the setup. The AD-1000 features many different digital audio output formats. The front panel power switch is a three position switch located on the front upper right hand corner of the AD-1000. The center position selects power OFF. The other two positions select either NORM or ADAT output format. The selected output format appears at the AES (male XLR), S/PDIF 15 pin HD connector and OPTICAL (optical plug nearest the edge of unit) outputs simultaneously with the appropriate format, level and impedance. For example, with the front panel switch selected to NORM, the XLR will output AES and the S/PDIF and OPTICAL outputs will output S/PDIF format. The AES output will be +4 volts pk-pk/balanced, unterminated, and the S/PDIF output will be 0.5 volts pk-pk /75/balanced (S/PDIF will drive balanced and unbalanced loads). When selected to ADAT, output is ADAT format on optical, with Audio Black clock signal (no data bits) output on the AES and S/PDIF outputs. AES/EBU Professional digital audio transmission format. Transformer-isolated balanced line output to a three-wire transmission line. Output Impedance: 110 Signal amplitude: 4.4 Volts peak to peak into 110 Sampling Rate Range: 3254kHz Connector: male XLR mounted on rear panel, pin 1 ground; pins 2 & 3 signal Note: Polarity of pins 2 and 3 is not important. Reversing pins 2 and 3 will not affect the digital audio transmission because the format is insensitive to polarity.

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.

4. Set SAMPLE RATE to the 6 oclock (unmarked) position. 5. Set the THREE POSITION SWITCH (located between the Sync Source and Sample Rate selectors) to either 16, UV16 or 20 as desired. When inputting a 20 bit signal: the 20 position outputs 20 bits with no processing. the UV16 position outputs 16 bits with UV22 encoding. the 16 position outputs 16 bits with triangular dither. When inputting a 16 bit signal: the 20 position outputs 16 bits unprocessed (whatever signal is input). the UV16 position outputs 16 bits with UV22 encoding. the 16 position output 16 bits with triangular dither. 6. NORM / ADAT Switch: Selecting ADAT transmits the ADAT output on the Optical digital output. When NORM is selected, the AD-1000 simultaneously outputs AES/EBU (Male XLR) and S/PDIF in optical and coaxial formats.

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General notes on ADAT Recording
The AD-1000 has the ability to output the ADAT digital format (on Toslink Optical) allowing you to bypass the A/D converters in the ADAT recorder and get the legendary Apogee sound on ADAT. The following pages contain information on how to accomplish this in a number of different ways. There are, however, some basic concepts that need to be understood first. The most common questions revolve around the fact that the AD-1000 is a two channel device and the ADAT is an eight track recorder. You will notice that the AD-1000 has only one optical output (and one optical input) and the ADAT has the same number and type of optical connectors. When in ADAT mode (power switch to ADAT), the ADAT transmitter in the AD-1000 transmits eight channels of information which is just the original two channels (left and right) duplicated four times. If you were to put all eight tracks of an ADAT into input, you will see four pairs of information with the left channel of the AD-1000 going to tracks 1, 3, 5 and 7 of the ADAT and the right channel of the AD-1000 going to tracks 2, 4, 6 and 8 of the ADAT. Thus, you can record onto tracks 3 and 8, or 5 and 6, or 1 and 4, or 7 and 8, and so on. This of course, begs the question of How do you record four different channels worth of music simultaneously on to four tracks of the ADAT (assuming that you have two AD-1000s)? Unfortunately, you cant. At least not on one ADAT. Remember, the AD-1000 is only a two channel device and there is only one connector, so there is no way to get those other channels into the ADAT. You can connect as many AD-1000s as you wish to that many ADATs (see diagram on Using Multiple AD-1000s) and record lots of tracks simultaneously, but only two channels per ADAT. Obviously, you can go back and overdub on the remaining tracks. This brings up the question of using multiple ADATs controlled by a BRC (Big Remote Controller). Recording on to a single ADAT (with no BRC) is easy (see note on Recording Without a BRC later in this section). Any time a BRC enters the picture, even with a single ADAT, sync must be provided to (or from) the BRC. For digital equipment to communicate properly, all the gear must be running synchronously, that is they must all have their clocks lined up so that they do exactly the same things at exactly the same time. The BRC provides sync information to the ADAT; therefore if the AD-1000 is providing a signal to the ADAT, the BRC must have the same timing (clocking) information as the AD-1000. Imagine having two different drummers in two different rooms playing the same song. They are both providing a beat (clock) to the song, but in order for the song to work they have to play together, therefore it is necessary to provide both of them with the same information (sync) and they need to be able to hear each other. Digital audio gear must all be playing together to work properly. A separate timing signal (usually Word Clock or video sync) is used to accomplish this. Usually one piece of gear is designated the Master and everything else slaves to this master clock. The AD-1000 is remarkable in that it can either be a master or a slave depending on the requirements. Please see notes on Recording With a BRC. The last (hopefully) question that needs to be addressed is How does the AD-1000 receive ADAT? Thats easy it doesnt. Remember that ADAT is an eight channel format and the AD-1000 is a two channel device. The basic AD-1000 cannot decode this information and make anything sensible of it, nor does it have a way to pass it through so the AD-1000 cannot be hooked up in the ADAT optical loop. (The special version AD1K-ADT can decode this information and convert it to AES/EBU format two channels at a time. See later in this section.) It is recommended that the AD-1000 be connected (via optical) only to the particular ADAT being recorded onto. The optical input on a standard AD-1000 is not an ADAT input. The AD-1000 will output AES black (Audio Black clock signal with no data) from the AES output when in ADAT mode. The ADAT format is a 16-bit format. That is, it records with 16-bit resolution per track. The AD1000 is a 20-bit converter and can output 20-bit data even in ADAT mode. The AD-1000 gives you three choices for output resolution 16, UV16, and 20 (16-bit triangular dithered output, 16-bit UV22 processed output, and unprocessed 20-bit output, respectively). With a 20-bit output, the ADAT will truncate (cut off) the extra 4 bits, which obviously is not the way to go, so you are left with a choice of UV or not UV? We generally recommend that the UV process not be used twice on a signal that remains in the digital domain (does not become analog again) and we recommend against doing any digital signal processing after the signal has been UV encoded (please see UV22 Caveats page 49).

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AD-1000 Operating Manual However, many people have come to depend on the superior audio quality of using UV22 to record their 16-bit tracks, and report no significant audio damage by using UV22 again when the recording is mastered. The bottom line here is that you need to be the judge of your own recordings. Listen to the music as it goes through its various stages of tracking, mixing, editing, sequencing and mastering. If you like what you hear, then its OK. If you dont, then its not. Music is art, not science.
Recording with the AD-1000 to ADAT (without the BRC)
1. Connect the output from your console or microphone to the AD-1000 XLR input connectors. (When viewing the AD-1000 from the rear, the Left XLR is on the left side) 2. Select any analog input (+4, 10 or MIC) on input select switch. 3. Set the front power switch of the AD-1000 to the ADAT position. 4. Select the SYNC SOURCE to CRYSTAL. 5. Select the SAMPLE RATE selector to desired setting (44.1 or 48kHz). 6. Connect the optical cable from your AD-1000 optical output to the ADAT optical input of the destination ADAT (When viewing the AD-1000 from the rear, the optical output is on is on the right side). 7. Set the ADAT unit to DIGITAL IN. 8. Arm the desired tracks of the ADAT (left channels are odd numbers 1,3,5,7 and right channels are even numbers 2,4,6,8).
Recording with the AD-1000 as the master (BRC as the Slave)
WC Out 15-pin HD 48 kHz In 75 Coax Fiber-Optic Cable BRC AD-1000 Sync Source: Crystal BRC: Ext Sync 48kHz In

Optical Out

ADAT Digital In

Digital In Sync 9-pin D

Sync 9-pin D
ADAT w/BRC AD-1000 as Master
1. Connect the output from your console or microphone to the AD-1000 XLR input connectors. (When viewing the AD-1000 from the rear, the Left XLR is on the left side) 2. Select any analog input (+4, 10 or MIC) on the input select switch. 3. Set the front power switch of the AD-1000 to the ADAT position. 4. Set the SYNC SOURCE to CRYSTAL. 5. Set the SAMPLE RATE selector to the desired setting (44.1 or 48kHz). 6. Connect the word clock cable (75 coax) from the WC output of the AD-1000 (on the 15 pin HD connector) to the 48 kHz input of the BRC. A special cable PS-1000/AD-1000 Cable is required for this. It may be purchased from your Apogee dealer or see the diagram to build it yourself. 7. Set the BRC to external sync. (EDIT, EXT SYNC to 48K Input) 8. Connect the optical cable from your AD-1000 optical output to the optical ADAT input of the destination ADAT. (When viewing the AD-1000 from the rear, the optical output is on is on the right side). 9. Set the ADAT unit to DIGITAL IN. 10. Arm the desired tracks of the ADAT (left channels are odd numbers 1,3,5,7 and right channels are even numbers 2,4,6,8).

In positions 1 oclock to 4 oclock, the output of the AD-1000 (AES or S/PDIF) will be a 16-bit signal on channel A (left) and the 4-bit plus tone signal on channel B (right) from each of the selected track pairs. In positions 5 and six oclock, the output (AES or S/PDIF) will be a normal (recombined) 20-bit two-channel signal from the selected group of four tracks.

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AD-1000 Operating Manual Special notes and restrictions: 1. ADAT format cannot be transmitted while the AD-1000 is set to digital input DIG. 2. ADAT format cannot be transmitted and received simultaneously. As a result, the AD-1000 cannot be connected in an optical loop. 3. While transmitting ADAT, the AD1000 outputs AES black - a sync signal with no data. 4. While synced to video, the AD-1000 will only transmit 44.056 kHz or 47.952 kHz sample rates in ADAT mode. 5. While synced to either AES or S/PDIF, the AD-1000 will only output 44.100 kHz or 48 kHz sample rates in ADAT mode. 6. While synced to an external Word Clock, any sample rate received can be transmitted.
Operating the AD-1000 with the Tascam DA-88
The Tascam DA-88, an eight channel modular digital multitrack (MDM) recorder, has only the proprietary TDIF (Tascam Digital Interface) for its digital inputs. TDIF is specified as a 25-pin "D" connector which would take up almost half of the AD-1000's rear panel. Since ADAT is also a eight-channel digital format which uses only the small optical Toslink connector, Apogee decided it would be easiest to output the ADAT format and then convert that signal to the TDIF format external to the AD-1000. Thus was born the FC-8, Apogee's ADAT to TDIF (and vice-versa) format converter. The FC-8 is the simplest and best way to get into a DA-88 digitally with the AD-1000. There are other devices that convert AES/EBU into two channels of TDIF, but the FC-8 can be viewed as an extension of the AD-1000 itself and was designed to be just that. It would be useful to read the previous discussions regarding using the AD-1000 with ADAT, as the same basic principles apply (i.e. the AD-1000 being a two channel device and the DA-88 being an eight- track recorder) and in fact, you will primarily be using the ADAT output of the AD-1000 (and converting it to TDIF). Using the DA88 is somewhat more simple in that there is no BRC or master controller to contend with, but care must be taken to ensure that all devices in the digital recording chain are properly referenced. When recording onto a DA-88 digitally, a separate word clock must be provided to the DA-88, since the TDIF receiver does not support a clock signal. The FC-8 will sync to the incoming ADAT signal and provide a Word Clock output to be connected to the DA-88 Word Sync input. If using the IF-88AE (Tascams AES to TDIF Converter), it will sync to the incoming AES and provide a Word Clock output. In both cases the DA-88 Clock should be set to WORD. Recording on to the DA-88 from an AD-1000 1. Connect the output of your console or microphones to the AD-1000 XLR input connectors. 2. Select the appropriate analog input (+4 CAL, 10 CAL, or MIC) on the INPUT SELECT switch. 3. Set the front panel power switch of the AD-1000 to ADAT when using the Apogee FC-8 Format Converter. If using the Tascam IF-88AE, select NORM for an AES output. 4. Set the SYNC SOURCE switch to CRYSTAL. 5. Connect an optical cable from the OPTICAL OUTPUT of the AD-1000 to the ADAT IN of the FC-8. When viewing the AD-1000 from the rear, the optical output is on the right side. Alternatively, if using the IF-88AE, connect an AES cable from the AES output of the AD-1000 to one of the AES inputs of the IF-88AE. 6. Connect a TDIF I/O cable (Tascam part number PW-88D) between the TDIF I/O connectors of the FC-8 (or the IF-88AE) and the DA-88. 7. Connect a 75 BNC cable from the Word Clock output of the FC-8 (or the IF-88AE) to the Word Sync input of the DA-88. 8. Set the clock of the DA-88 to WORD. 9. Select DIGITAL IN on the DA-88 and arm the desired tracks. Remember that the left channel of the AD-1000 will go to tracks 1, 3, 5 and 7, while the right channel goes to tracks 2, 4, 6 and 8 of the DA-88. Note: When using the High Resolution option (AD1K-PRT) with the DA-88, follow the steps outlined in "20 Bit Recording Using the ADAT" for coding and decoding the 20 bit signal to and from the DA-88. With the FC-8, the AD-1000 will only see the ADAT I/O, so you can fool it into thinking that it is dealing with an ADAT machine.

A 12 volt 7.2 Amp/hours lead-acid battery (NiCad batteries are not recommended) can be used for portable or field operation. You will need to interface the battery leads with the 15 pin HD connector see drawing for pinouts. For battery information contact Eco Charge in Boulder, CO 1-800-361-5666. The AD-1000 can also be powered from a car battery. Other 12 Volt sources Any good regulated 12 V DC, 1.5 amp linear power supply will sufficiently power the AD-1000. We do not recommend using a switch-mode type power supply. In addition, we do not recommend the use of the TT-1200 table-top PSU designed for the AD-500. The AD-1000 takes more current than the TT-1200 can provide.

Battery Operation

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AD-1000 HD15 connector (J1) pin numbering viewed looking into the connector on the unit from the outside (numbers are as molded on the connector itself)
JGRAY (from PSU) WHITE (from PSU) +12v rtn (gnd) +12v (Bat) SHIELD (from PSU) CHASSIS GND SHIELD SHIELD S/PDIF WC UNBAL 75 (BLACK)
AD-1000 HD15 connections S/PDIF

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JGRAY (from PSU) WHITE (from PSU) +12v rtn (gnd) +12v (Bat) SHIELD (from PSU) CHASSIS GND SHIELD LEFT (WHITE) SHIELD RIGHT (RED) SDIF-2 SHIELD WC UNBAL 75 (BLACK)
AD-1000 HD15 connections SDIF-2

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Appendix I UV22 Super CD Encoding
Squeezing more performance from a standard CD is not a new idea. It began with adding white noise, called dither, to the digital audio. Plain dither was followed by different flavors of dither noise, then a process called noise shaping and more recently various forms of so-called bit mapping. Independent listening tests confirm that these systems either color the recordings we are trying to preserve, or compromise the audible noise floor. Five years in the making, Apogee UV22 Super CD Encoding is an entirely different process. UV22 does its job without sonic compromise, and without adding a sound of its own, preserving the sound stage and tonal balance of the original 20-bit source. The effects are even audible on original 16-bit recordings. UV22 Encoding adds an inaudible, high frequency bias to the digital bitstream, placing an algorithmically-generated clump of energy around 22 kHz. Much as the bias on an analog tape recorder smooths out magnetic tape recording non-linearities, UV22 silently captures resolution up to and even beyond 20 bits on a standard, 16-bit CD. In addition, this inaudible carrier smooths the rough edges of even the most inexpensive CD player or external converter. UV22 makes your recordings sound better on all listening systems. Running already-mastered 16-bit sources through a UV22 processor delivers sonic improvements that any user can realize on equipment they already own. UV22 is a very special information carrier: it is not a new flavor of dither noise. The truly unique statistical properties of UV22 guarantee a constant white noise floor, very similar in character to analog tape noise, no matter what the input source. If you listen to the noise on a UV22 encoded recording, you can hear a stable, accurate sound stage and faithful tonal balance more than 24dB into the noise just as you do on analog tape. Yet the UV22s low audible noise floor sits at the theoretical limit for a 16-bit system. Nothing is lost but a great deal is gained. In listening test after listening test, mastering engineers unanimously choose UV22 over all other systems. Many thousands of CD titles have already been mastered using Apogee UV1000 Super CD Encoders and the Apogees AD-1000. Noise-shaping and bit-mapping systems modify the noise floor by changing it from a familiar white noise to one that has been radically modified. Their proponents theory says that the 96 dB CD noise floor is not low enough to avoid interfering with our listening pleasure, and that our ears would prefer a big dip (about 12 dB) in the noise floor in the 23 kHz area, with an accompanying HF boost of as much as 30 dB. What they forget is that few CD releases actually approach the 96 dB noise floor: the noise of almost all sources is significantly higher than this and swamps any of the claimed benefits. In addition, in the process of shaping the noise, these systems are also shaping audio information hiding in what they call noise, which results in noticeable shifts in image and colored tonality of the music. At Apogee, we believe the dynamic range of CD to be fine for many current applications. As a result, we dont try to modify the noise floor. Instead, we make it transparent, allowing clear, clean audio information to be heard up to 30 dB into the noise just like analog. This information is captured and encoded on to CD and can be appreciated on any CD playback system.