Be sure to save the container for any future ship- ments of the unit. Accessories The following accessories are shipped with the AD This burn-in procedure involves powered operation at elevated temperatures to isolate units that could possibly fail due to infant mortality. Refer to page 31 for further information. Page Oscillator This is used primarily for headroom alignment and testing. The digital oscillator is set at 15dB below full scale as a default.
These switches can be changed by using a small screwdriver. The table below lists the available test tone levels and the corresponding switch settings. The Soft Limit feature of the AD, unlike conventional peak limiters, does not have a precise kick-in point.
Page Output Resolution Selection And Uv22 The AD 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 can also act as a stand-alone sync generator.
The position with the above it signifies a bridged input of 5k for the AES. The front panel power switch is a three posi- tion switch located on the front upper right hand corner of the AD The center position selects power OFF. Page Advanced Operation The default position is with all switches set to the off position. The switches serve the following functions. This means the DC inputs will be passed through the direct coupled stages all the way to the conver- sion stage.
Page Options And Enhancements Operation: 1. Optical input is available via the TosLink connector on the back of the AD Thus, you can record onto tracks 3 and 8, or 5 and 6, or 1 and 4, or 7 and 8, and so on. Page Bit Recording 6. Connect the word clock cable 75 to the 48 kHz input of the BRC. It may be pur- chased from your Apogee dealer or see the diagram to build it yourself. Page Bit Recording Option Using good quality Apogee 75 cable, connect a good quality video sync blackburst generator to one of the sync inputs BNC connectors on the rear panel of the AD Page 42 2.
ADAT In 3. Instead, we make it transparent, allowing clear, clean audio information to be heard up to 30 dB into the noise — Page 48 bit CD. Maybe worse. The UV22 ver- sion was by far the best. I put material through the UV22 at below —60 dB and you could clearly hear the low-level information.
Like many people, you may be guilty of skipping the technical diagrams and jumping to the last page for the conclusions. Understanding how digital audio works is akin to getting into the details of how MIDI controls musical instruments… Page 51 Timing jitter can cause more subtle effects. In digital to analog converters for example, the location of instru- ments across the audio sound stage can become less focused.
Page 52 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. Page 53 MDM systems. As a result, the AD repeats its two channels across the eight channels in the ADAT the first AD channel appears on the od-numbered tracks, while the second appears on the even tracks. Page 54 AD Operating Manual on a twisted pair of wires enclosed in an outer metal shield.
The common mode rejection is typically 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 position switch providing maximum input flexibility. Rotating the selector clockwise, the next five positions select microphone input gain in 10 dB increments.
See page 31 for details of this procedure. When either of these positions are selected, the multi-turn CAL trim pots are enabled. The phantom voltage ramps up and down slowly for quiet activation and uses highly accurate resistors for optimum performance.
Soft Limit functions as a selective peak limiter. Typical peak limiters are very abrupt and can spread unwanted harmonics. With the AD, 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. Filters Apogee has long been known for filter technology — the result of years of proven, proprietary designs.
The AD- 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 output can be either bit resolution or bit. Used by virtually all major mastering facilities, UV22 captures the resolution and detail of the bit conversion in a bit word length; information that would normally be lost.
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. 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 When a signal is within 0. This is used to calibrate the analog to digital conversion levels. SDIF outputs are also optionally available on this connec- tor. 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 excel- lent soundstage detail. Whenever possible, the AD should be the digital timing source for the digital studio. Additional information on the sync capabilities of the AD is included on page 25 of this manual. Please click here for detailed specifics regarding our specialized packing process that separates us from the rest.
Our Warranty.
0コメント