The SDR-4000SL Reference CD Processor is a limited edition reference instrument crafted in the Spectral engineering department and individually programmed and calibrated by its designer Keith Johnson. Relatively unlimited time and resources have been utilized to achieve our ultimate objective: Engineer the most sophisticated and sonically accurate CD player in the audio industry. Those that are familiar with Keith Johnson's credentials and previous achievements in digital design know this objective is not taken lightly. As with previous editions of our SDR components from the 1980s and 1990s, such as the SDR-1000 and SDR-2000 reference digital components, it ta1ces our engineers multiple design generations to arrive at an ultimate model. The SDR-4000 has been previously produced in three highly regarded versions, the original SDR-4000S, the revised SDR-4000Pro which incorporates the exclusive HDCD "Long Filter" technology and the SDR-4000SL with our Ultradrive system. It has taken Spectral engineers five additional years to develop our most uncompromising generation, the SDR-4000SV. In the SDR-4000SV, Keith Johnson and the design team address the continuing perfomance objective to create the ultimate SDR-4000 and again redefine the possibilities of the compact disc medium for the most demanding musical applications.

The Spectral SV Technology Delivers Superior Analog Performance
Constant research in our fundamental technologies drives component advancement at Spectral. When we introduced our recent SHHA Generation 3 line section modules in the DMC-30SV reference preamp, they proved to be a game changer. Our customers and our dealers proclaimed the DMC-30SV a "revelation", redefining preamplifier performance in the finest music systems. Now the "Super Veloce" technology is adopted for the high-level output section of the new SDR-4000SV CD processor with exceptional results. In reality, all digital source components are a complex combination of systems and as much dependent on the quality of analog circuits as digital. This a~~eness. of analog's critical role has driven Spectral d1g1tal design practice to focus the same demanding performance criteria we use in developing our preamplifier line sections. In the SDR-4000SV the line amplifiers and power supplies are replicated from the uncompromising DMC-30SV reference preamp. In all probability, there may not be a more sophisticated analog output section in a digital component today! However, there is more that is required to surpass our previous analog efforts. A newly designed DAC summation I/V amplifer is optimised to support the higher speed and gain of the the SV output section. The hand-calibrated
passive equalizer filter section is also realigned. Taken in total, the fully discrete high-speed class A amplifier topology of the SDR-4000SV takes analog performance to a new level in a digital component.

Spectralock 2 Delivers Superior Clocking
The analog amplification improvements are not the only advances made in the SDR-4000SV, a new proprietary clocking system reduces jitter and clock error to previously unattainable levels. Our new Spectralock 2 system employs custom cut VCXO crystal reference oscillators and redesigned master clock system to lower clock jitter and reduce fields which can induce jitter. This extreme precision has resulted in virtually unmeasureable peak jitter using the finest existing instrument test systems. The ultraprecision Spectralock 2 master clock is joined by new drive control software which increases data cache rate and suspends data transmission from the drive to DAC for longer periods of zero activity. 1bis silent transport running lowers noise and field emissions. The results of these changes are lower clock interference and lower electrical activity which can effect the internal timing of the DAC.

Spectral SDR-4000SV is the Industry's Finest CD Playback System
The industry leading performance achieved by the first SDR-4000 twelve years ago continues with the advancements of the SDR-4000SV today. No other digital component for CD playback approaches the challenges of 44.1 digital with the technical and design superiority realized in the SDR-4000SV. This superiority starts with a fundamental architecture dividing 4000 structure into eight fully independent and powered digital and analog sub-systems. Each sub-system has been realised with breakthrough technology and componentry using "best practices" employed in SOTA high-teclmology instrumentation. With zero cost-cutting and the finest components in existance,
benchmark performance in 44.1 reproduction has been achieved. The addition of the new SV technology and Spectralock 2 master clock reference to the SDR-4000 result in the finest performing CD playback system in the industry, delivering unrivaled performance of music recorded on compact disc.

Features
- Exclusive HDCD'!' 'long Filter' high performance decoding software.
- Custom 20 bit balanced DACs with fully disaete
- Class A high current summation amplifiers.
- Spectralock 2 .... ultra-low jitter master dock reference.
- All discrete wideband topology totally eliminates integrated circuits from the analog signal path.
- Discrete passive equalization is individually tuned.
- High speed, Class A SHHA G3 line molule output section derived from DMC-30SV preamplifier.
- Independent ultra-isolated 'Floating Power' supplies for all nine player sub-systems.
- Better than one part per million data precision.
- UltraDrive custom built mil-spec avionics optical drive.
- Ultra-premium construction beltless design.
- Extended cycle life and precision glass optics laser.
- Fully modular drive packaging accommodates
- Full field servicing and updating.