INFO
NEW DA-218
CRYOGENIC Digital Processor

DA-218 Cryogenic Digital Processor Info

Ultimately it's the Music!
You'll hear new details, an extended frequency response in the music to 100 KHz,
while sensing the energy and the space of the original performance.
More excitement, more dynamic, more Pure Music!


Technological advances abound, starting with Cryogenic Treatment

Experiments in super-conduction at very cold temperatures (-300 deg. F), which changes a wire's normal resistance into zero resistance and transforms the molecular characteristics of the wire into a super-conductor were achieved years ago. Today it has been found that cryogenically treated audio cables, exhibit improved sonic characteristics. Why does this cryogenic treatment make them sound so much better?

The manufacturing process of copper wire and copper sheets causes molecular changes in the copper. When hot copper is pulled through a small hole to form a wire or rolled into thin sheets to make PC boards the stress of being heated and reshaped inadvertently causes crystal lattices and boundaries to be formed, at about 1,000 crystals per foot. Unfortunately, the boundaries formed by this crystal lattice structure impede the natural flow of electrons, causing excessive brightness and a lack of focus in the musical soundstage.

When dissimilar metals are joined, crystal boundaries are also formed, similar to those from at copper wire and copper sheet manufacturing. Soldering a resistor lead to a PC board causes stress and more crystals are formed. There are thousands of solder connections and copper crystal boundaries formed in the signal carrying copper layers in each standard assembled PC board.

The DA-218 processor is cryogenically treated! Cryogenically treating the DA-218 at -300 deg. F., using a special computer controlled process, markedly reduces the crystals that had formed in the copper when the PC board was made or when all the electronic parts were soldered to the PC board. The cryogenically treated DA-218 processor articulates the purest and most vivid sounding music possible. Discover hidden details and new aural pleasures in your old CD's elevating them to Hi-Resolution format quality and on an equal footing with a LP record's innate duplication of live music.

Ultimately it's the music!

New nonmetallic shielding! A silver-copper shielding has been integrated into the DA-218 chassis and cover to protect the power supplies and analog circuits from radio frequency interference (RFI), i.e. Cell phones, TV, etc. The silver-copper shielding will also protect the analog circuits from electromagnetic interference (EMI), i.e. power lines, power transformers, microwave ovens, etc. This RFI /EMI silver-copper shielding is non-magnetic. Magnetic shielding (steel) located near analog circuits will alter the sound. An additional full faraday shield completely surrounds the digital circuits, a step that few others have taken, but significantly protects the analog circuits from radiated high frequency digital noise that decreases the width and depth of the music's sound stage.

State of the art Up-Sampling Technology! All input digital signals (32KHz satellite TV, 44.1KHz (Red book) regular CDs, 88.41KHz DAT tapes, DVD) are up-sampled to 96KHz using a state of the art very high accuracy algorithm. The algorithm's very accurate number crunching yields a total harmonic distortion plus noise (THD+N) of -117 db. This extraordinarily precise up-converter combined with the new DA-218 software will make all your old CDs sound better than you have ever heard them before! Its like getting a completely new better sounding CD collection of your favorite music.

Over-sampling! After converting the input signals to a 96 KHz sampling rate the data is then sent to an over-sampling digital filter where it is over-sampled to an incredible 768KHz (8 x 96KHz ) sample rate and a 24 bit word length before being sent to the D/A converters. This very high sample rate requires extremely accurate timing at the Burr Brown D/A converter ICs which is provided by the system's master clock with a +/- 2 pico sec. phase jitter and is used to re-clock the data and clocks just before the D/A conversion. The DA-218 uses new sonically advanced software that programs the up and over sampling filters, extending the musical image's transients and air.

NEW Shielded Quantum Noise Filters! Hand soldered Bybee Quantum noise filters are connected to the AC input lines, close to the power supplies, to remove quantum (shot noise) from the A.C. line voltage. Removing Quantum noise before the A.C. line voltage is used to energize the digital and analog power supplies, reducing the power supplies output noise and the processors analog noise floor, increasing dynamics and resolution. Separate power supplies are used for the digital and analog circuits. There are independent left and right analog power supplies for each channel with 13 distinct voltage regulators, designed to have very low output driving resistance with extremely low output noise associated with the processor's power supplies. This low driving resistance and extremely low output noise is very important when powering the left and right analog circuits so as not to contaminate with noise the DA-218's neutral and musical tonality.

Balanced signal 4 layer printed circuit board! The DA-218 four layer PC board was elected to support balance signal stripline designs which maintain the balanced signals throughout the entire processor, reducing signal jitterand radiated digital noise. It is manufactured using the very latest high frequency dielectrics and materials that support low clock jitter. and both design and materials were very carefully chosen, by both measurement and listening to conduct the very purest analog sound quality achievable. It has also been designed for convenient upgrading, in that important ICs have been inserted and not soldered into sockets. There are also extra socket locations in both the digital and analog sections to support future designs and facilitate upgrade ability to future formatsand D to A conversion . Furthermore, optoisolator buffers are used to isolate all digital to analog control signals.

Vibration / damping! Special nonmagnetic damping plates have been added to the chassis and cover. These nonmagnetic damping plates have been added to further dampen any vibrations from corrupting the sensitive analog circuits. To further minimize any possible vibration, five custom isolating feet have been strategically positioned on the bottom of the chassis providing excellent protection from a variety of vibration sources.

Both measurements and long sessions of critical listening, have led to the components chosen such as Caddock and Roederstein resistors, and the polypropylene capacitors used in the analog section. Only selected high quality and the best sounding components are used throughout the converter for exceptional low MTBF* and high musicality, (* low Mean Time Between Failures means a longer trouble-free life!)

The power supplies have over 100,000uf of filter capacitance, worthy of a small power amplifier. New custom capacitors made to Dodson Audio's specifications are used in the analog circuits, nourishing textural Timber in the Musical Image, and are connected to thirteen, low noise DC regulators, including multi-stage regulation for the critical analog stages. A voltage supervisor senses low line voltage and instructs the microprocessor to mute the analog outputs during power up or power failure, very important in safeguarding your audio system from possible undesirable noise glitches.

Input signal jitter is dealt with and removed by clocking the input signal into a storage memory, then re-clocking the stored input signal out of the memory using a master clock with a +/- 2 Pico sec. of phase jitter. After re-clocking the signal, balanced differential drivers send the very, very low to no jitter clocked signal to the 24/96 D/A converter chips. These very pure very low jitter digital signals and clocks produce "Incredibly Pure Music".

Hand soldering using special silver-bearing solder is used to ensure the highest sound quality possible from all critical devices and plug-in boards. The up and over sampling board, left and right D/A converter modules, Bybee Quantum noise filters, faraday shields on top and bottom of the mother board, and left and right analog filters are either hand soldered or hand adjusted and matched. Dodson Audio's exclusively written test software that programs an Audio Precision cascade tester is used to measure, adjust and verify the stringent processor test requirements. After the main mother board is completely assembled, an audio Precision Cascade tester is used to test the processor's assembled motherboard prior to cryogenic processing. After cryogenic processing, the processor board is again tested using the Audio Precision Cascade tester to ensure cryogenically improved performance, before final mechanical assembly into the chassis.

The assembled processor and chassis is then burned in for 48 hours. An Audio Precision Cascade tester using Dodson Audio's custom test programs is used to adjust and hand match the D/A left and right converter chips. Left vs. right channel phase is hand adjusted to +/- 0.1 degrees phase. These final tests are run after cryogenic treatment and burn-in to optimize and ensure the processor's highest performance at the time when matching, testing and making final critical adjustments. These custom test programs include multi tones tests that simultaneous generate 1/3-octave signals that are digitally generated and used to stimulate the processors digital inputs. Simultaneous 1/3 octave multi signal testing represents a more accurate depiction of music for left and right D/A chip set matching and the analog filters hand phase adjustments. Multi-tone software is also used for many other tests. Our custom multi tone testing software is much more accurate and precise than standard generated single frequency testing methods

Hand-matched, select grade Burr Brown Series "K", 24-bit ladder sign-magnitude DAC's provide excellent low level linearity and dynamic range, with a guaranteed ultra low Total Harmonic Distortion plus noise of .0008%.

The analog filter, which follows the DAC's is a Frequency Dependent Negative Resistor type that has a very flat frequency response. Because no audio signals pass through the active part of the filter there is low minimum distortion and phase shift, very important for sound purity. The audio signal path is DC coupled from the D/A converters' IC's to the output connectors. A DC servo keeps the output DC voltage offset level to a low .005 volts, preventing sound degradation due to DC offset biasing of DC coupled power amplifiers and speakers. The analog filter' bandwidth following D/A conversion can now be greatly increased because of the high 768KHz sampled and 24 bit data being fed to the D/A converters chips. The new analog filter has a bandwidth of a super wide 100KHz . This very wide filter design will allow you to hear more pure music than ever before! These new 100 KHz wide analog filters in both the left and right channels have only +/- 0.1 degrees of intrinsic phase shift, this is very important to ensure proper phasing of the music. All the frequencies of the music spectrum must reach your ears at the same time, the same way you hear live music. At final processor testing, using multi tone tests, the relative phase shift left vs. right channel is hand adjusted to have +/- 0.1 degrees phase shift. This is an absolute must-have requirement to reproduce a proper size soundstage, precise musical instrument location in the soundstage and overall musical purity. This is the closest you can get to the precise musical sound vs. phase relationship you hear when listening to live music!

No sound debasing nickel plating is found in our connectors! Our custom PC board connectors have silver plating directly over a copper base metal and then are gold plated over the silver for lasting protection. Costly, yes! but the music passing through our high quality connectors remains pure and true. It's nice to know that Dodson Audio Model DA-218 Converter is a handsome unit, made with a silver faceplate (or a black faceplate can be special ordered) that is scratch resistant, and that comprehensive error reporting, using front panel LED's is constantly available. It's even nicer to know that the Dodson Audio Model DA-218 has been designed for convenient upgrading to new formats, in that the important IC's have been placed in sockets, not hard wired to the board and are thus easily removable, should better IC's be developed. And, as better signal handling algorithms are developed, the master microprocessor is also re-programmable, so the Dodson Audio D/A converter will be a source of listening pleasure for a lifetime. But, Ultimately it's the Music!

"Leading Edge Technologies produce state-of-the-art music for your listening pleasure"
We invite you to try the Dodson Audio's DA-218 Cryogenic Processor at selected dealers around the country and please do compare it to units costing much, much more.


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