Wadia 27 Decoding Computer Review

The Wadia 27 Decoding Computer is a landmark high-end digital-to-analog converter from the mid-to-late 1990s. Released around 1996 at approximately $8,450, it represented Wadia’s sophisticated approach to digital playback at a time when many audiophiles still preferred analog. It sits in the lineage of Wadia’s pioneering “Decoding Computer” designs and remains highly regarded by enthusiasts of multi-bit DACs.

Design and Technology

The 27 is a substantial, beautifully built unit housed in a precision-machined aluminum chassis with a minimalist front panel featuring only a blue fluorescent display. All control is handled via a solid metal remote.

Key technical features include:

• DigiMaster algorithm — Wadia’s proprietary digital filter, optimized for time-domain performance rather than pure frequency-domain metrics. It uses dual Motorola DSP chips performing 16× oversampling, combined with 4× in the DAC stage for a total 64× resampling rate.
• DAC section — Fully balanced configuration using Burr-Brown PCM1702 multi-bit chips (four per channel in later descriptions of related models).
• Processing — 24-bit digital input capability with 22-bit resolution.
• Digital volume control — 50 dB range in 0.5 dB steps (100 steps). This allows the 27 to drive power amplifiers directly, bypassing a traditional preamplifier.
• Inputs — Six digital inputs: two ST glass-fiber optical, two BNC coaxial (S/PDIF), one AES/EBU (XLR), and one Toslink.
• Outputs — Balanced XLR and unbalanced RCA (usable simultaneously). Low output impedance and high current capability.
• Other — RocLoc clock recovery for strong jitter rejection, extensive power supply regulation (dozens of regulators), and modular design allowing software/hardware upgrades.

Later versions included the 27i (added ClockLink for reduced jitter when paired with compatible Wadia transports) and 27ix (added 96 kHz support and selectable filter algorithms).

Sound Quality

Contemporary reviews (notably Robert Harley in Stereophile) placed the Wadia 27 among the very best digital processors of its era, alongside the Spectral SDR-2000 Pro and Mark Levinson No.30.5.

Listeners consistently praised:

• Transparency and resolution — Exceptional clarity and natural timbre without harshness or digital glare.
• Soundstaging — Wide, deep, and well-defined, with precise image placement and a strong sense of space.
• Bass — Powerful, tight, and impactful with excellent control and authority.
• Dynamics and involvement — Highly communicative and engaging; music feels spontaneous and realistic. Many noted a “live” quality when driving amplifiers directly.
• Overall character — Clean, detailed, and musically coherent rather than overly analytical. It extracts substantial information from CDs while remaining enjoyable over long listening sessions.

The digital volume control is a major practical advantage. Used near the top of its range, it preserves resolution and allows a simplified system path that many found superior to inserting a preamp.

Pros

• Outstanding build quality and industrial design.
• Highly resolving yet musical presentation.
• Excellent digital volume control for direct amplifier drive.
• Flexible connectivity for its time.
• Strong measured performance (low noise, excellent linearity, good jitter rejection).
• Upgrade path (software and hardware) kept units relevant longer.

Cons

• Expensive when new (and still commands strong used prices for well-maintained examples).
• Limited to 48 kHz maximum on the original 27 (96 kHz only on the later 27ix).
• Best results often require a high-quality transport and careful system matching.
• Remote control range can be narrow.
• As a 1990s design, it lacks modern features such as USB, DSD, or network streaming.

Verdict

The Wadia 27 Decoding Computer is a classic high-end DAC that still impresses today for its combination of technical sophistication, build quality, and engaging musical performance. It was designed in an era when engineers focused intensely on extracting the best possible sound from Red Book CD, and it succeeded at a very high level.

For collectors and enthusiasts who value multi-bit conversion, time-domain optimized filtering, and the ability to run a minimalist digital front-end, a well-maintained 27 (especially a 27i or 27ix) remains a compelling choice. It may not match the latest high-resolution streamers in format flexibility, but for pure CD playback and classic high-end digital sound, it continues to deliver a level of involvement that many modern DACs struggle to equal. Highly recommended for those who appreciate the golden age of high-end digital audio.